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  1. Exactly as the title states, RunVSE has released emissions compliant tuning for the LM2 Duramax in the Sierra and Silverado platform (pre-refresh). https://runvse.com/2020-2022-3-0l-lm2-duramax-emissions-compliant/ https://youtu.be/lGBM54eJ1Vw
  2. "Opinion ‘Car Talk’ host: Independent auto shops deserve the right to repair your car September 28, 2022 at 7:00 a.m. EDT (Washington Post staff illustration; images by iStock) Ray Magliozzi is one half of NPR’s show “Car Talk,” a longtime independent repair-shop owner, a Dear Car Talk columnist and a car reviewer on CarTalk.com. When your car breaks, what do you do? Okay, after you utter a certain word? You have to decide where to take the car to get it fixed, right? You really have two choices. You can go to the dealership or an independent repair shop. However, some car manufacturers don’t want to share key information for diagnosing and fixing cars with independent shops — and that’s something that’s not only bad for repair shops but also bad for you. As a radio host who has advised thousands on their car problems and as an independent shop owner myself, I know all too well that car owners benefit when they have more choices. Congress is considering a national “right-to-repair” law, and lawmakers need to pass it to protect your rights as a consumer. Story continues below advertisement Back in the old days, when people were still switching over from traveling by mastodon, you repaired cars with your eyes, ears, nose and hands — and, if you were desperate, a Chilton repair manual. Now, you often repair a car by first plugging a computer into the on-board-diagnostics port and seeing what the computer tells you is broken. So, what’s the problem? Carmakers and their dealerships want to maintain control of modern diagnostic tools, which forces customers to come to them for repairs. Even though independents are willing to pay to license these tools, dealers see an advantage in exclusivity. Dealerships have always had certain advantages. They have better coffee in their waiting rooms. Heck, they have waiting rooms. They have clean restrooms that don’t double as auxiliary air-filter storage. They also work on your particular make of car all day, every day. So they might be familiar with an oddball problem because they’ve worked on 4,000 Camrys. Story continues below advertisement Independent shops are small businesses, run by individuals — some of whom are terrific people and mechanics and some of whom will blame your car troubles on demonic possession and give you essential oils to fix it. But independent shops have their own advantage: price. Their labor and parts costs are usually much lower — hey, who do you think is ultimately paying for the dealerships’ coffee and fancy couches? Some research has found that dealers, on average, charged as much as 20 percent more than independent shops for the same repairs. This article was featured in the Opinions A.M. newsletter. Sign up here for a digest of opinions in your inbox six days a week. There’s also the matter of distance. Not every town in the United States has a stop light, let alone a dealership for every car brand. There are 16,752 franchised car dealers in the United States, according to the National Automobile Dealers Association, but there are nearly 240,000 repair shops — meaning that for a lot of people, an independent shop is the only nearby option. Story continues below advertisement At Car Talk, there are times we’ll strongly recommend an independent shop for standard work like brakes, shocks, the engine and regular service. And there are times we’ll recommend going to the dealership, like when you have a particularly rare problem that might be unique to your make and model. But at the end of the day, you should take your car to the dealer to be fixed because you want to not because dealers have hoarded all the key information. Beyond the information needed to diagnose and fix your car, dealerships also want to maintain control of your car’s telematics. What are telematics? Well, now that everything is connected to the internet, your car can notify your dealer when your car needs an oil change or has a blown sensor. Using the software they’re denying to independent shops, the dealer can then diagnose the trouble code, call you and schedule a repair. Most modern cars already have this ability. Car manufacturers point to the importance of keeping your car’s data safe — including your location, say — as a reason to deny independent shops access to these tools and codes. They are right about the need for data security, but part of privacy is that you should be the one to decide who has access to your data. Story continues below advertisement At least 17 states have laws on the books stating that your vehicle’s data belongs to you. Many independent repair shops will need to invest in tools to keep customer data secure, but just because they’ll need to invest doesn’t mean they can’t compete with dealers. Lack of choice — and competition — is never good for the consumer. So consumer groups and independent shops are promoting what they call right-to-repair legislation, guaranteeing consumers more choice by requiring automakers to license their data with independent repair shops. The voters in my fair state of Massachusetts approved just such a law in 2020. In 2021, 27 states introduced or passed similar legislation. Beyond those state laws, there’s a national push to protect consumers and independent shops. H.R. 6570, a national right-to-repair bill, has been sitting with the House Energy and Commerce Committee for months. My Car Talk colleagues and I know not everyone will support right-to-repair laws. Dealerships won’t like the level playing field. Mechanics might not like how much work they’ll actually have to do. Still, this is an issue everyone else can get behind. If you own something, you should be able to choose where to repair it. "
  3. Hopefully you guys can help me out here a bit. I have a 2014 Silverado CCSB Z71 5.3 with 38000 miles on it. I was driving to work this morning and had the reduced engine power alert come up in my DIC along with the stabilitrak light. I pulled over, shut the truck off and re-started a few times with no success in clearing the codes with drive cycles. While driving, the transmission was banging gears pretty hard and the torque converter was clunking worse than "normal, by GM standards". I got to a good spot to park the truck and that is that for now. I am anticipating a tow to the dealership as I am about 20 miles away from it now for what will hopefully fall under the powertrain warranty as my bumper to bumper was up 1 months and 2k miles ago. Anyone have a similar problem with this or any insight as to what it may be. Im iffy on driving it home to scan it, as I dont want to compound any problems. I drove the truck Saturday night, probably 60 miles on the highway with no issues and it sat in the garage until this morning. Help me out, internets!
  4. 2011 Chevy 1500 LT crew - 144k miles So, after countless hours of searching, I’ve decided to post here in desperate need of help. My truck is currently in the shop, and on its 3rd mechanic trying to diagnose/fix the issue. Originally I was getting an oil pressure sensor unit code months ago, and about a month of driving later, and I finally lost my oil pressure gauge (dropped to zero) but the truck was perfectly fine. No loss of oil, etc. So I brought it in to get it fixed and change the oil - they put an OEM part in and changed the screen. Reset everything and I picked it up, a few moments later my check engine light returned. Scanned it when I got home, same error code - active. Checked for oil leaks, etc - nothing. Returned a month later for them to fix it, they put in another OEM part and new screen…drive it 3 miles down the road, and it trips again. They’ve checked the valve cover gasket and checked the PCM, everything seems fine. The truck is not burning oil either. I’ll add that my oil pressure gauge on my dash works fine now since they swapped sensors too. Everyone is stumped on what to do, and I’m about to potentially go down the rabbit hole of ‘throwing parts at it’. Starting with the PCM and then the valve cover gasket, and many thousands of bucks potentially. Does anyone have the slightest idea what’s going on? The PCM is throwing no other codes either, he has graphed and checked it. Is it possible for the PCM to be corrupt without it giving errors, etc? The tech is a 30 year vet, and a family friend - so by no means is he stupid. But this has stumped two other techs with equal experience too. Now my truck is past inspection, and with my Check Engine light on, it’ll never pass. Plus I’m still half way on my loan, so just selling it isn’t an option. Help!!!!
  5. Hey guys. Long story short. I have a 99 Sierra 6.0L. Battery completely died and in the process of charging the battery and trying to start it, my ecm b fuse blew. I replaced it but now my speedo is pegged all the way to top speed and my gear selected icons won't indicate what gear I'm in. I tried searching forums and the web but couldn't find anything on GM trucks for this issue. What am I going to have to do? Is it possible to reset the ecm? Am I missing another fuse? I only find ECM "B" and couldn't locate "A". I'm a bit lost with electrical.
  6. I'm looking for a replacement ECM for my 1998 Corvette. The part is only good for the 97 and 98 model years. Changes were apparently made for model years 99 and newer. Delco part number if useful is: 19332289 or 16238212. This part has proven much more difficult to find than I anticipated. If you or anyone you know own one, please let me know. I'd love to get my car back on the road!
  7. I've tried searching for this, but came up empty so far. So I'm hoping someone may have seen or heard of this one. For years my 06 Tahoe Z71 4WD 5.3, would properly reset the oil life back to 100%. Now for the last 2 oil changes it has decided that it doesn't want to. On the previous reset attempt it would only reset to 82%. On the most recent Oil Change it only reset to 52%. This isn't really a big problem just quite odd. I did note that when it only reset to 82% that it still took the same 10K or so miles to get down to 0%. Of course when it didn't fully reset the first time I reset it several times all going to only 82%. Now that it's only resetting to 52% I'll have to see how it does.
  8. 2000 Suburban 5.3L. I'm having problems with the injector circuit for cylinder 3 in my car. I removed the connector on the injector and verified that it's getting power (constant 12V when key in ON position and 14V when engine is running). When a test light was put on the ground terminal it illuminated but didn't pulse. When I looked at the voltage though, it was bouncing all over between 0 and 14V. I turned the car off and noticed the ground terminal had 1.7 kOhms resistance to ground when the engine is off. Thought that was funny as it shouldn't be connected to ground when the car is off and if there was a short, the resistance should be 0. I traced the wiring and didn't see anything wrong. I then found a diagram for the ECM connectors, located the terminal for the cylinder 3 injector (ironically terminal #3) and found the same 1.7 kOhm resistance to ground at this terminal. This was the terminal on the actual ECM not the wiring harness. 1. Is this sufficient evidence that the ECM is bad? 2. Can I just go to a junkyard and pull an ECM out of another 2000 Suburban with the 5.3L and put it into my car with no problems? 3. If not, does anybody have experience with flashmastersecm.com? Judging from ebay, they look reputable.
  9. I just recently parked my Chevy 1500 Silverado WT to do some routine work. when I attempted to start it up all that happened was the key turned and the instrument panel lights went out and there was an audible click from that area. I got out and check the battery connections, battery (which is fairly new) and the starter relay on the fuse block. I even tried jumping it off of a running vehicle, but still the same problem exist. All the lights and radio work fine so I assume the battery is not the cause for the sudden death. I tried swapping the starter relay with another relay (one that was for fog lights which I don't have) and I still get the same response. I then took out the ignition relay fuse and found the power side and connected it to the ground terminal and nothing happened. I repeated the same steps on the starter relay and I heard the starter click. I have never had any starting problems (with the exception of the key getting stuck from time to time) with the truck or any kind of work done recently. I don't have a anti-theft system as far as I know. Since I'm sure the problem is electrical in nature could anyone tell me what could be the cause or what I should investigate next? I understand there could be many failures in the system that could cause this, so I will try and seek out the most likely causes first. Hopefully I can avoid having to tow it to the dealer for a diagnosis and repair with the help of a knowledgeable and friendly mechanic. Thanks in advanced for anyone who can help me.
  10. 2019 Denali ultimate. So far the ultimate headache ache. I’ve had the rear window leak, front glass removed and headliner replaced. Dealership left erase fingerprints all over new headliner. The rubber wasn’t tucked back in properly. Windshield had sealant all over interior and exterior. Botched job. They sealed rear window.. Now it leaks again In the same spot. I’ve turned into GM a claim and they sent to a senior advisor. I still Haven’t heard from the,. Left multiple messages, the dealer has left messages and no return calls. ‘’Also had the ECM replaced which was. 5 DAY PROCESS. Squeaks in dash that has been in twice until I finally Fixed it myself. Front speaker wasn’t seated good. The plastic piece on rear window exterior had to be glued on twice. Service engine soon light for something with transmission. And now also light on for service anti lock brakes. Since thanksgiving when truck was purchased it’s been in the shop for over three weeks. All I really Need is a customer service senior advisor to return a call and allow a rear window replacement at the dealership. Anyone have a connection? Regretting trading my f250. Could see where the Denali could be nice truck had it not been in shop every other week.
  11. Hi guys, So, I recently had to replace the heater's blower motor in my 99 GMC Jimmy. In order to remove the blower motor, I had to take out the Battery, ECM, and Coolant Reservoir. After finishing up and reconnecting everything, I tried to start the truck to check if the blower motor worked (it does, but only has one speed now). When I tried to start the truck, I got one tick (as if the battery wasn't connected well), but then all the lights turned off and I couldn't turn the key back or remove it. I'm unsure of how to proceed here.
  12. I have read so many posts, and messaged a few people across two forum sites; however I am still confused about a gear change on the 2014-2018 (mostly on the 2016+) trucks. I know the parts are available, and it is possible to change the physical gears. Where I can’t seem to find an answer is about reprogramming the various separate computers. If I understand it correctly, the available programmers can ONLY reprogram the ECM for tires and gears which only fixes the speedometer, and no one can reprogram the transmission, vvs unit, or the ebcm (abs), which is why some get the abs and brake codes after gear swaps despite reprogramming the ECM. I can’t help but believe this will also have a severe negative impact on the truck’s stabilitrak system, which I want to keep working properly. Is there anyone who HAS ACTUALLY swapped their gears AND reprogramed their trucks on this site? If so, what specific components (ECM, transmission, etc.) were reprogrammed? Does your truck have any error codes including the abs/brake lights/codes? What programmer was utilized for the programming? It also appears GM changed one of their computers for 2016+ trucks so access is limited and it’s harder to get into the computer for changes?
  13. Maybe this will help anyone who has a truck that turns over, but won't start. P1682 is the code on the computer... Here are the technical details on this code: P1682 Chevrolet Description There are 2 ignition 1 voltage circuits supplied to the Engine Control Module (ECM). The first ignition circuit is provided by the powertrain relay, through a fuse. This ignition 1 voltage circuit supplies power to all the internal ECM circuits associated with the throttle actuator control (TAC) operation. The second ignition 1 voltage circuit is supplied by the run/crank relay through a fuse, and is used to power the remaining internal ECM circuits. If the ECM detects a voltage difference between the 2 ignition 1 voltage circuits, DTC P1682 will set. P1682 Chevrolet - Ignition 1 Switch Circuit 2 Possible causes - Faulty ignition switch - Ignition Switch harness is open or shorted - Ignition Switch circuit poor electrical connection - Faulty Engine Control Module (ECM) When is the code detected? The ECM has detected a voltage diference between two circuits Possible symptoms - Engine Light ON (or Service Engine Soon Warning Light) - Possible no crank or start I decided to replace the ignition switch because that's what other people had done and it was cheaper than a dealership diagnostic. Besides this one code, my instrument console also threw up warnings about servicing the traction control, anti-lock brake system and some other alarming messages. Including that the engine power was reduced! The ignition switch on my 2011 Silverado is part # 40 in this diagram: To get at it you probably need to drop the interior trim panel below the steering column. Once that's done you need to pull out the steering wheel tilt lever part #20. It should unplug strait out with a screwdriver. Then you unclip the plastic shroud part #22 and #1 Then you unclip the connector going to the Key Chip Sensor #2. And unclip the wiring harness that plugs into the ignition switch. CAUTION: You might have a red plastic locking clip in the harness that needs to be disengaged before the connector will come out. The next step is to remove the lock cylinder. You'll need a pick. Here is a video of someone doing it on a similar vehicle: You can then unclip the Key Chip Sensor #2 and set it aside. You will then have to unhook the white key sensor that that's mounted on the ignition switch case #3 you just removed the key cylinder from. You'll need a small screw driver to push on a plastic tab to unlock it. Once that's done it should rotate easily for removal. If you break it off, it's not a big deal since it's part of the ignition switch you're replacing... even so, I'd practice on this one so you'll be better at removing it if need be in a later step: You can now remove the ignition switch. You'll need two small screw drivers or nails to push into the two square holes to the left and right of the "black hole" shown in the picture below: This video is also good to watch before starting this project: Now the ignition switch I pulled out of my 2011 Silverado was GM Part #25733005 ; D1485F (DO NOT USE) The dealership I contacted said that part had been replaced with GM Part# 22887691 which makes sense since the previous one died. Hopefully the new part lasts longer! Installing the switch is pretty much a reverse of the original process. The only issue is that you need to get your ignition cylinder and the switch gears aligned properly. I had to remove and replace the ignition switch and lock cylinder (and the key security chip reader) a few times before I was able to get the gears on the switch to be correct. (The guy in the second video explains how to align it, but I either didn't pay close enough attention or couldn't do it quite right) You'll also need to clear the code once your vehicle is working again. Hope this helps someone else!
  14. Hi I'm brand new here but I've been a frequent snooper but I've finally come to a problem I can't find discussed before. The other day while driving my check airbag light came on it comes and goes but never stays for more than a minute. So thinking it had to be a sensor I went to oriellys and had my error codes checked only to reveal much more problems than I expected. The codes were: p0237(which I have had sinse I replaced my fuel pump so I think it's just faulty especially because the fuel gauge hasn't been right either i got another replacment I haven't had the time to install though),P0480,P0463,P0455,P0332,P0327,C0040,C0035,U1041, I think it pulled up 14 total codes but many were duplicates I think he said. my truck a SCSB 4.8 with the work trim 2005 model and just under 145,000 miles The oriellys guy suggested it may be a failing ECU and after a little research I'm thinking he may be right but I'd just like to see if any of y'all might have some ideas. Also the lights flicker like they did before I replaced my alternator and the voltage jumps around on the needle like crazy but I think I may have just picked up another faulty part butluckily that can be replaced under warranty. Other than the flickering lights the truck doesnt show any obvious signs of problems. Any and all help will be greatly appreciated needless to say it ruined my evening yesterday hah
  15. My truck a 2008 silverado 5.3 is throwing a p0641 and p0107 code the second being the map sensor. The truck was at the shop for a few days and my mechanic states that the truck needs an ecm. He said he was able to verify that allof the sensors on this circuit are functioning well. Im hesitant to buy an ecm however can you always see that sensors are working through a scanner. What if it is just a sensor? He also showed me thay all of the sensors on the circuit were only running on 2 volts.
  16. I did a search on here for replacing the engine computer and was surprised for not finding much ! We have an 05 Silverado with a 5.3 in it. The other evening, my wife went to see a friend and when it began to storm, she decided to leave. She went out and the truck was dead, no click, no crank. I went to get her and tried to jump start it (while it was still storming) and arcs came off of the negative terminal when the cable touched it. I stopped and decided to disconnect the battery till morning. Next day I go over there and reconnect the battery and the engine fans start running with no key in the ignition (probable reason why the battery arced the night before)! Battery voltage was down to under 11 volts so I took it to get checked since it was 5 years old. Got a new one, connected it, the truck fired up, and all seemed well. Took the truck home, parked it and 2 hours later I go to leave in it and the engine fans are running again ! When I drove away, I got about a mile from the house and the check engine light started flashing. Codes that came up were P0300 and P0480, random misfire and engine cooling fan code error. So..... I checked what I could, but then on Monday took it to an automotive electrical guy. He ran his diagnostics and while it was there, the fans came on by themselves again with no key on. He check his schematics, ran his checks and suspects the computer has some kind of fault. He said to get a salvage computer and he would re-flash it for my VIN. I checked around and found one local, but also looked online and came across "All Computer Resources" in Miami FL that sells reprogramed ECM / ECU / PCM automotive computers. I wasn't sure what to do, so called another electrical repair guy for another opinion. He said it could well be the computer, but would run his own checks before just replacing it. He was adamant about not using a salvage or reconditioned computer. Said he has been there, done that, and will now ONLY install new OEM replacement GM computers and flash them. Anybody out there have good or bad luck with a reconditioned computer ? Any thoughts or suggestions ?
  17. I have an issue with my 2007 ½ GMC Sierra 2500HD LMM truck, that I really need so experienced help understanding. My truck has 150,000 on it and has never been in the shop. I put an H&S Mini Maxx tuner on it, in 2011, after removing the DPF and exhaust from the turbo back. Everything ran great until 3 weeks ago. I was driving to work and the check engine light came on. I checked the code and the DTC code was “PO642 Sensor Reference Voltage A Circuit Low”, but the truck was running fine. I did some research and discovered it was this could mean the crankshaft sensor is bad. No big deal. I when to NAPA and bought another and installed it. Tried to clear the code and it came right back seconds after clearing it. Did a little more research and discovered it could be a Fuel Rail Pressure Sensor. However, this is too expensive to replace without being sure, so I called my local Chevy dealer and asked him if he could trace the DTC code to the sensor and avoid me randomly replacing stuff. He said yes, should only take an hour and $130.00 so I set up an appointment for Thursday of that week. On Sunday, prior to the appointment, I had the truck warming up in the driveway, when I noticed it stopped running. I tried to restart it and it would not start. I checked the fuel and there was fuel I the fuel filter. I had to run to an appointment, so I took my wife’s car. When I returned, the truck started right up. Strange, it will start when it’s cold, but not warm. I duplicated this several times and never saw any new DTC codes. I decided to have it towed to the dealership. It sat there until the scheduled Thursday appointment. The service rep called me and said there is a short somewhere in the wiring harness and three sensors that would produce that code and it could take up to 10 hours to find it. He also said the battery was completely dead and they had to push the truck into the shop. I authorized the work. The next day he said the ECM was bad and was causing the low voltage issue. I authorized a rebuild ECM. He later called me and said the tech could not communicate with the ECM through the ODBII port and the truck would not start. He plugged in the old ECM and couldn’t see it either. I went down to the shop and confirmed that my Mini Maxx cold not see the ECM either. Strange After doing more work, he determined that the Glow Plug Module had power going to it, but nothing after it and that the module was bad. Strange, I’ve never had a glow plug issue or fault. They replaced that, and still couldn’t see the ECM or start the truck. After more work, he unplugged the Mass Airflow Sensor and could now see the new and old ECM, no error codes in the new one, and the truck starts. Plugs the MAS back in and the error code appears and the truck won’t start. So now he has a new MAS on order. He stated that the bad MAS could have taken out the Glow Plug Module and the ECM. Does this make sense to anyone, because it makes no sense to me? Did he do something that could have caused all these modules to blow?
  18. Hello All, I have an ongoing issue I was hoping to get a few opinions on. A few weeks ago my truck started to gradually spudder when I was cruising with the RPMs jumping very slightly when it did. I did not notice it being related to transmission as it was shifting just fine so I figured ignition/timing. The check engine light came on with the error codes p0016 and p0300, camshaft/crankshaft misalignment and multiple misfires, respectively. I needed some brake work done anyway so I took it in to get serviced and they replaced the distributor rotor, cap, wires, sensor and all the coil packs. It worked fine for about a day and then the light came on. I've been working nights on a turnaround the last 2 months and just do not have time to take it in so I waited. About three days after the truck finally just died on the way home. It flashed low oil pressure/low oil level and the pressure dropped to zero as it was dying. I checked all the fluids and for leaks, everything was fine and where it should be. I had it towed to firestone (only thing that was open on the weekend). They quoted me $1300 for a new ECM and new distributor install. My truck is only work $2500-3000 and I'm coming up on paying that for repairs after the last round and this one. They said my ECM was sending commands but not receiving any and the distributor was not sending anything to the ECM. So my questions, the ECM I can see as being a potential for replacement, but the distributor seems like it would have more tell-tale signs if the gear drive was cracked or worn. They also did not mention anything about the ICM or the timing chain, which to me seem like the most likely culprits here. I really do not want to fork over $1300 only to find out my timing chain is stretched or the gears worn and have to fork over another grand. I'm going in tomorrow to inquire, but any help here would be greatly appreciated. Thank you for your time.
  19. Hey guys, So over the weekend I put a new (to me) transmission in my truck (2003 silverado 1500) upon finishing the job I went to start it up to start pumping the new fluid through, but the truck will not turn over. All lights, radio, ect.. come on, but the truck will not turn over. Also, even after I have pulled the key out, the front marker lights, rear running lights, and dash lights all will not shut off. There is a high pitched ringing coming from the engine compartment, which, along with the lights shuts off when I pull the fuse for "ECM B". Initially I thought this was the Park-Neutral safety switch, which was cracked while we were installing it. The only idea I have left is that there is a small wire that comes out of the harness and attaches to the back of the engine right behind the passenger side cylinder head that was broken while installing the dipstick, I cannot find any information about what this wire is for or where it is supposed to be attached. ANY help would be much appreciated!!!
  20. I can't seem to find the cause of my high idle, around 1000rpm. So far I've replaced parts with Borg Warner, nothing cheap. Fuel pump, filter, etc. Complete ignition system top to bottom Rebuilt the Throttle body Changed coolant thermostat and sensor, hoses and fluids When I step on it hard I get an engine light. It will run ok but not as strong until I shut it off, wait 20 seconds and restart and it's ok. I would guess the next thing would be the ECM.....? Thanks, David
  21. Original stock ECM (PCM) from my 2003 GMC Sierra 2500HD with 6.0L gas engine. I purchased a Black Bear Performance tune and opted to keep my stock ECM. I've since sold the truck and just found this in my basement. Indoor heated storage since 3/2010. Looks like Black Bear currently charges $100 for a core, so how about $75 shipped to lower 48 or make offer.
  22. Was driving the other day and noticed my left turn signal was constantly on . Checked all bulbs even replaced a few just in case . I unplugged relay and still left turn was on. Didn't see a reason to replace it since at the time it didn't seem to be the problem. Now after a few days of this I noticed the dash warning lights blinked on as I was driving . Like the truck was being started. The Multi-display even went into the block pattern boot up. Right turn works fine and sometimes left will blink until I step on brake light. then it displays always on ( sometimes left will go out when driving a while) really weird issue. I fear my ECM is about to go out. The only thing not stock about this truck is a aftermarket Kenwood radio professionally installed . and some aftermarket turn signal lights in front with LED's but no mod to wiring. Thanks in advance for any insight on this issue. I guess I should also add I have indicators on the side mirrors.
  23. Hi I'm new to the forum and i am having some big time electrical difficulty with my truck. Its an 04 chevy silverado 1500 with the 5.3L. Got home one night with it then went back out the next morning to start her up and noticed before i even turned the key my key fob, door locks, auto interior lights, and radio were all not working what so ever. i then cranked the car and it turned over and started for about a second or 2 and then sounds like it shuts itself off. my scanner tool is not communicating with the truck at all either. i have checked every fuse, some grounds, and the fuel pump and nothing there shows any sign of malfunction. i have researched a good amount on the problem and looks like it could be a possible bcm? just looking for further ways of pinpointing the problem without going to the dealer and spending $220 for them to do it. any type of advice or locations to check would be greatly appreciated. Some prior history: 2 front wheel hubs changed 2 days before code popped up for knock sensor week before(changed them yesterday as truck sat sadly broken in driveway) and had the typical silverado problem with the abs causing skipping from bad sensor so i had the brake fuse out until i put the new hubs in. but fuse looked fine. Thank you for your time
  24. Good morning, everyone! I'm new to the board but I hope to frequent it pretty often instead of being one of those one and done posters. So, here's my situation: My 2000 Silverado 1500 z71 transmission is getting pretty tired (215,xxx miles) and I've picked up a wrecked donor 2004 Silverado 1500 with a rebuilt transmission that I know to be functioning well. Both have the 5.3L with the 4l60e trans. I'm looking to swap the engine and transmission from the 2004 into the 2000 - my thought is everything will bolt up properly due to not much changing between 99 and 06. My concern is can I use the pcm from my 2000 on this newer engine that we're putting in or will it require a new wiring harness and pcm? Are there any other things I should be concerned about? Thanks for your time! Reyn
  25. Helping a buddy out here...or at least trying. He has a 96 suburban k body 5.7, and on a recent trip it just died. He drove it about 250km (155miles) and parked it for three days. When he went to come home he got about 50km down the road and it died, not slowly, just running then not. On the side of the road, in the dark, he determined the fuel pump was not pumping, but the fuse was good so his conclusion was failed pump. Had it towed home and we were going to change the pump, but before we started, we decided to take a code reading as the check engine light is lite. Could not establish a connection between the reader and the vehicle, and upon further inspection of fuses, found the ecm-l 20amp blown. Aha you say.....changed the fuse and instantly blows when the key is turned to on. Did a check of all the pin terminal connections and wiring harnesses, and even looked under the fuse block as someone mentioned on here under a different thread, to look for mouse invasion, but all looks "good". Does anyone have an idea, or has expierienced the fuse for the ecm blowing so quickly? On a whim, we got another known good ecm and plugged it in with the same results. We even tried a new fuse without the ecm connected and it blew the fuse the same. Are we missing something or is it auto wrecker fodder? Thanks for reading, any suggestions could win the lucky submitter a beer. Steve
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