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Anyone have a check engine light show up then go away and come back? Code uo129 lost communication with brake control module, UO101 lost communication with transmission Control Module. Went to bed with no check engine light, woke up in the morning for work and noticed the truck would not remote start. When I go in to head to work noticed check engine light. After work ran codes. Shortly after getting codes and using google to research check engine light was gone. Went for a drive never came back on. Woke up this morning it was on again. Can anybody relate?

I did a search here for it but came up empty. Last week, my Check Engine Light came on briefly while on the highway. Just before and after that I noticed a reduced lack of response to giving it more throttle. I had a local guy pull the CEL code and said it came up as #7 Cylinder Misfire. I'm at 55,000 miles and am off warranty. The truck is a '14 with a 5.3. Any suggestions, or thoughts how serious this may be ?

Hello I got a baffling problem with my 2017 Chevy Silverado 1500 LT with the 5.3 L and Z71 package in it. I got a U1510 code and U1501 code. The U1510 says it’s a LIN on bus communication issue. Now this was about the end of August when that happened. Looked at a few things couldn’t really figure it out and didn’t have the time to look because the truck seems to be running fine. About 4 days ago my service brake trailer starts flashing on my dash when I’m not even towing a trailer (the last time I did was about 5 days before this). Now I take it to my step father who owns a garage and has worked on chevys for years. Now the U1510 code is still there when we scanned it but the U1501 code is gone but now on top of those codes there’s a U1037 code which is lost communication with trailer brake control module, P0562 which is low system voltage for Chasis Control Module, B127E code which is Front video display output signal, and C0800 code which is control module power circuit below voltage threshold for the power steering control module. The truck driving it runs perfectly fine, nothing abnormal at all. So thinking the trailer brake might be a separate issue we checked that out all the wiring etc and nothing wrong with it. So for the other codes we went and checked all the grounds on the truck thinking it might be a ground issue and all them seem to be good. We are starting to think maybe it’s a PCM, ECU problem because of all the random codes being thrown in every direction as well as codes in the system before disappearing. Any advice or help would be appreciated!!

Hey all I'm wondering if anyone has experienced anything similar to my ordeal? So I have a 2020 GMC Sierra 1500 5.3 V8. It only has 1500 miles on it and we just pulled our camper with it which only weighs 4500#. It pulls fine doesn't squat much and I use a weight distribution hitch. We took it to the campsite unhooked and I parked the truck. The next morning I started up the truck and the service engine light came on. After about 5-6 starts it cleared and is no longer on. It seemed to drive fine even when the check engine light was on. I'm wondering if me parking the camper going forward and reverse a few times made the gas mileage so bad it triggered the warning light?

2007 Silverado 5.3 V8 with AFM with 180,000 miles Truck had lifter ticking sound and white smoke upon every start up which would go away after a few minutes, no check engine light Replacement list : - headgasket - valve gaskets - upgraded drivers side valve cover - valve stem seals - intake manifold gasket - exhaust manifold gasket - 8 new afm lifters - 8 new non-afm lifters - head gasket bolts - engine coolant temperature sensor - spark plugs - spark plug wires - fuel injectors - water pump - thermostat - cam sensor - crank sensor After completion of engine reassembly no longer had white smoke upon start up and no ticking sound but flashing check engine light code p0300. Code p0300 was for cylinder #1, #4, & #7 Moved coil packs between cylinder #1 and #2 to see if coil packs was bad but no change. Set engine at TDC before installing the rocker arms. All bolts have been properly torque and no parts have been left unplugged or uninstall. Any possible advice would be helpful

Hi! In April, my Yukon was throwing codes P0172 P0175. Local GMC dealer in Louisiana "fixed", by replacing some sensor. Traveled to PA, codes came back on. Local GMC dealer fixed by replacing BCM, body control module in June. Now my check engine light is back on! Power train Warranty ran out 2-3 weeks ago. Also had extended warranty, which also ran out at 5 years, which was Sept. Code onstar says its throwing now is P0430, all of the codes from I can find are related to exhaust system. My question is are these 3 codes related??? Could this be something they will have to fix under warranty, given it's related and has been worked on several times? If not, what does this mean? Catalytic converter bad? Help! My husband is being laid off in the next week. So, obviously finances are tight. Yes, obviously itll be fixed regardless, just trying to plan and cut back elsewhere if needed. This has been a great vehicle! As luck has it, trouble starts when warranty runs out. Really wanting to trade, but waiting on new body Adding mileage if matters, 91K

19 Silverado TrailBoss V6: Several times now the truck stalled out when in park and idling. I try to restart and it turns over but won't start, take the key out and try again a couple minutes later and it works but the check engine light is on. Prior to this starting, last week while driving 60mph on highway the truck shuddered/shook a few times and the check engine light came on. OBD reads out P16AF & P16A7 as the error codes. Dealership said they ordered a new part...anyone having issues like this? Also, still no fix on the backup camera glitching out. Someone is gonna get hurt and GM has been made aware and I filed it with NHTSA. No fix yet...

1996 GMC Suburban K2500 7.4 check engine light goes on for a few days, then off, then back on again. I put the OBD and it shows code P0135, Oxygen sensor bank 1 sensor 1. If I'm not mistaken, this is the upstream sensor on the driver's side. I did a web search and came up with a lot of hits, some sensors are labeled as "heated sensor", some are not. I have a few questions. 1. Should these be replaced in pairs, both upstream and downstream? 2. Does anyone have a part number, or link to the correct sensors. Thanks.

I am a long time GM customer and currently own a 2009 GMC Yukon Hybrid truck. It has been an ok experience but just recently the truck started to do some strange and unsafe things. It started out revving up without pressing the pedal or hesitant to accelerate after stops and then moved on to stalling in the middle of driving and would give me a warning of REDUCED ENGINE POWER, SERVICE STABILITRACK AND SERVICE TRACTION CONTROL but would only do it every blue moon. Here recently I was leaving somewhere and the car begin to shake and shake and then stalled out after those codes popped up. I called the dealership and set it up for an appointment. They got me in and the day I was taking it to them it gives me the reduced engine power warning and I noticed the car went from a rough idle to an even rougher idle increasing more and more as I'm driving. Finally I hear 'CLUNK' and then all of a sudden its not just a rough idle, the engine is shaking VIOLENTLY. I turn the car off. Other times when the car would give me the warning of engine power being reduced, I could turn it off and wait a second and turn it back on and it would magically reset for a random time period before it did it again. I was about 2 mins out from the dealership so I made my way there and as I'm pulling it the engine starts to do that crazy shaking thing...everyone literally stops and stares at me, probably trying to figure out if I'm about to blow up! They get it in and the tech is super alarmed by that shaking and said he had never seen or heard anything like it. They pull the codes and replace the throttle body position sensor under an extended coverage offered by GM. After they fixed it, I'm notified that one of my engine mounts broke and I now have to produce $1,000 to fix it!!! The engine mount is what broke during the engine freak out during the 20 minute drive to the dealership because I heard it! When I get my car back it now wont go into hybrid mode anymore and its idling super funny... up and down...up and down and I can now feel every shift the engine makes and the start up and turn off even rattles now and my engine ran so smooth before this you could balance a penny on the engine! I'm so upset because GM says this is my out of pocket expense. However this only occurred because of their defective part! I'm taking it back in whenever the dealership calls me back(been waiting for hours) and they will see why the engine is idling unevenly and "recheck their work". I'm so sad and after talking to a GM rep who so rudely informed me that they did their part on fixing the throttle body and to just shovel out $1,000 that is not not their problem, it s actually a point of frustration. My husband and I have own 6 GM cars that were a pleasure to buy and drive but we will never buy another GM car again!

10/29/2018 - took delivery of my 2019 Denali Ultimate 11/10/2018 - Wife drove truck from Brownsville, TN to Jackson, TN and back. On the way back, the digital instrument cluster and heads up display went black. Came back about 8 to 10 seconds later. Later that evening, I get into the truck to drive to the end of the driveway to get the pizza from the delivery guy (yeah, call me lazy, but we do have a long driveway) - upon starting the truck, the brake, stabilitrack, ABS, check engine lights come on along with "Service PCM", "Check Brakes" and "Speed Limited to 62mph" messages on the digital instrument console. Called OnStar and they confirmed and sent an email. 11/11/2018 - Took the truck to local dealership. There were DTC codes and they pulled them. Dealership stated they contacted GM Engineering and were awaiting a response. I also mentioned the high pitch whine issue when at steady throttle. They were able to recreate the whine and were unsure of where it was coming from. They said they thought it might be the sound system. That didn't seem consistent with me as it is always when the truck is at steady stated load as if it were a hydraulic whine from the drive train. 11/12/2018 - As if by happenstance, there was a software update available this morning. I let it install. Afterward, when I get into the truck and the "GMC" logo displays on the digital instrument console, it blinks on and off sporadically. Sometimes it shows nothing at all. Other times, it just shows a horizontal line across the display. 1/27/2019 - Today I was driving from my home in Brownsville, TN to Southaven, MS with my family to attend a cheer competition for my two daughters. Driving at around 70mph, the typical instrument cluster/heads up display going dark issue happened, but this time the entire truck violently jerked as if the engine shut off but the drive train, considering everything was still locked into gear, pushed the engine over until the power came back on a split second later. The radio was muted when this happened and it magically unmuted itself (as if the power blinked). That was the first incident. Three other times after that, the instrument cluster and heads up display went dark and came back on as if power was removed and it rebooted (individual objects on the display coming back on as the data from the CAN bus was received). - Anytime the temperature drops below what seems to be around 35F, lane keeping and parking assist becomes unavailable. - Anytime I connect my 8x16 trailer, the blind spot monitoring system for both the driver and passenger side goes nuts until eventually the system says it shuts it off on the console, but the mirror lights keep going ape shit... - This has only happened twice, but I have had the "ghost" trailer issue as well. The display on the center console acts as if a trailer is connected, but the digital instrument console shows the message "Trailer Disconnected" warning. How can a trailer be detected and disconnected at the same time? Are there any official GMC reps on here that can assist? Anyone else care to comment? Thanks in advance, Steve

Got error code PO449. Replaced both the solenoid and the EVAP Canister. Erased my OBDII. Drove about 80 miles mostly highway but with some stop and go. Turned engine off. check engine light came on immediately. Got code PO449 and PO128. PO128 is probably the thermastat and I saw prior positng. I am thinking (hoping) that maybe I did not drive far enough. Does the OBD system recycle with the engine idling? How much time? My kit came with a third air release part that is attached to the Canister with a hose that goes to the back. Easy to replace but I did not want to fiddle with what is not a problem. Any thoughts?

I'm posting this in a few different Chevy forums in the hopes of getting our story heard and getting some kind of useful advice or even just feedback. So I apologize if you have already seen this somewhere else. So I'll TRY and keep this to somewhat of a minimum, but no promises. Thanks for reading all the way through if you do. I just need some feedback and/or advice. My husband and I went down to our local Chevy Dealership and traded in our old worn out 03' Dodge Ram on 12/20/16 for a 1 owner 2008 Chevy Silverado 1500 and paid a little over $16k. LOVE this truck. It's gorgeous, all the fancy bells and whistles, (On-Star, XM, remote start, tonneau cover, etc.), seems very well taken care of, and doesn't have super low miles but seems about average for an 08'. The previous owner had bought the truck brand new in 2008 from this Chevy Dealership and had brought his truck for ANY service to this dealership. So they had all the service records. So we felt good about that. When we bought the truck, we were obviously aware of the current recall on the Takata airbag inflaters and it hasn't been fixed yet, obviously. The truck did have a light on for the airbag and the Chevy Dealership told us it was for the SDM Airbag Module. They said they would not be fixing that because there is no current recall for the SDM module in this truck. And he's right, there isn't. I searched the VIN on GM and no recall for the SDM module. So with that being the only issue (besides the Takata inflators) we decided to buy the truck. Here is what has happened since the night of 12/20/16. When my husband was signing all the paperwork for the truck, it also included signing up for On-Star which was done right in the office. As my husband started his drive home with his new truck, he got an email from On-Star for his new account about 5 minutes or so after he left the dealership. As most of you probably know, On-Star does diagnostics on any vehicle they have in their system and will send the account holder a report of their diagnostic check. So he read his diagnostics report and it indicated that there was an issue with the trucks emissions. That was all it said. Something we were not told about by the dealership and at this point in time there was NO check engine light on the truck. Our salesman was out of the office the following day, Wed. 12/21, so we couldn't get a hold of him until Thursday. Late Wednesday night I tried to remote start the truck and it wouldn't start with the FOB (remote start will not work with the CEL active). We started the truck with the key and that's when we noticed the check engine light. Not even 48 hours after we purchased the truck. We called On-Star and they told us the code is P0430 which is Catalyst System Low Efficiency Bank 2. Which is an O2 sensor or the cat. When we called the dealership and told them what was going on, it took them at least a week to get the service manager to call us back and get the truck in to test the code. OK so took the truck down to the dealership, service manager tested the code and came back out and told us it read as the EVAP Vent Solenoid and that the valve flap was stuck open and causing a vacuum leak. Told us that we should have been smelling gas fumes. No we have not. At all. Never had a problem with ANY fuel issues at all. Of course we thought that sounded a little odd. My husband is not an idiot when it comes to vehicles and from what we've researched online, P0430 is a VERY specific code to the catalyst system. But of course we TRUSTED the dealership and their service manager. Maybe they knew something that we didn't about Chevy codes. So they said they would call us to schedule an appointment to have it fixed. About a week later (this past Thursday 1/5/17), we took it in to get fixed and we drove away with our loaner. Next day, we pick up the truck, service manager said they replaced the solenoid and the check engine light was off. He also told us that the problematic EVAP Vent Solenoid they replaced had no power to it and that when they took it off, the wires were crossed. How the hell does that happen..? Obviously wires don't just cross on their own. So it must have been replaced in the past by some dingle berry that couldn't figure out where the wires go and the dealership didn't have any service records on the truck for replacing the EVAP vent sol. OR that was just a flat out lie. We were past thinking this was odd. At this point, everything that had happened since we traded in our Dodge for this truck and they only gave us $100 for our Dodge to refusing to replace the SDM module to the back door locks working intermittently after a couple days to giving us the run around about getting it in to get fixed to shotty service records about not knowing if the SDM module had or had not been replaced even though they had records that the previous owner had brought it in at least 3 separate time because of the SDM module light..honestly, I never felt good about this deal when they only offered us $100 for our Dodge. It was a worn out work truck but it was worth way more than that. I didn't want to do it. I never felt good about it and always felt like we were being played. But it was my husbands truck, I wasn't there when he bought the Chevy so it wasn't my choice. I trust my husbands judgment 100%. FAST FORWARD TO TODAY 1/10/17. The truck had been in the shop this past Thursday and Friday. It is now Tuesday and my husband was out in the truck and called me to tell me THE CHECK ENGINE LIGHT CAME BACK ON! He called On-Star and SURE ENOUGH, it's P0430. Same. Exact. Code. Hence the title I wanna drive the damn truck through the front of the effing dealership. He has called the Dealership about 5 times already and of course, no one is available. Not our salesman or anyone in the service department. Go figure. Only thing to keep in mind is we bought this truck USED and was classified as AS-IS sale. We knew that and were fully aware. BUT we are 100% certain that the definition of AS-IS does not include them make us FALSELY believe that the truck did not have an emissions problem, or ANY problem other than the SDM module. They specifically told us the only issue the truck has is the SDM module. The way this has worked out (On-Star emailing the diagnostic report literally 5 minutes after leaving the dealership, the code was already in their system) they HAD to have reset the check engine light on the truck probably when they brought it around for my husband to test drive it. They did not disclose that to us. They led us to believe the truck was in GREAT working condition and had we known about the emissions problem, we could have better a BETTER more ACCURATE decision on buying this truck. Or we could have negotiated the price and getting it fixed before deciding if we still wanted to buy it. They disclosed everything except for this emissions problem and the back door locks. And NOW even after they said they "fixed" it, the check engine light is back on which makes me think they just fed us a bunch of BS and they just reset the CEL light again to shut us up and stall us until we can no longer return the truck, imho. Buying AS-IS means you know EXACTLY what you are getting. We were deceived. Hands down 100% I believe they were completely deceptive and knew exactly what they were doing when they sold us this truck. So I'm not really sure if I actually have a question. At this point, my husband is already getting the phone numbers for Wells Fargo, our financier, for GM Corporate offices or complaint department who ever we need to call there, for the Attorney General of PA, and whoever else we need to contact. Unfortunately, they aren't BBB accredited so that's not an option. Any ideas, Thoughts, advice, similar stories, feedback for me?? Anything would help us figure out what we are going to do. Sorry it's SO long but THANK YOU so much for anyone that actually read the whole thing and is willing to give me some kind of feedback. Much appreciated!!

Hey, this is my first post so take it easy on me. Just have a few questions. I have a 2005 Chevy silverado 1500 z71 just in case that helps in any way. 1. Brakes - slightly squeaking / squealing more of a low pitch when breaking at lower speeds. not sure if just something like rust or anything, it is not a super loud screech so i'm pretty sure it isn't an indicator. Wondering if anyone knows what it could be. - Also, im not sure if it is maybe just how it is on that truck, but the brake pedal, I noticed when I press on the brakes, it kind of stays there for a brief second, and is able to move up and down a little without resetting back or pushing against and staying with my foot like most brake pedals seem to do. 2. Check engine code p0446 - have had the light go on and off for a couple of weeks. When fueling it cuts off at a little over 3/4 tank full. I believe it to be something clogged in that system based off of what i've read online. Wondering if anyone else has had the same problems or would know of what exactly to do. 3. Exhaust. - I notice the exhaust is 2.75" in diameter stock, which seems to make it more difficult to find any parts like exhaust cutouts or mufflers. Wondering if anyone has any suggestions for that stuff. Just looking to gather more info, get a better idea of what is going on, maybe learn from others who have had the same issues or resolved similar issues.

I have a 2011 chevy silverado 1500 that was acting normal but now it out of whack. Recently the traction control light says its off and on the display reading it says service traction control and service stabiltrack. Also my check engine light is blinking and dinging. The engine sounds rough and and when the tranny shifts down, it shifts hard. I hooked the truck up to a code reader and it came up with a code P0304 which is a misfire in cylinder 4. I already replaced the spark plug, plug wire, and coil. None of this fixed it. I did some looking around and I have read that the throttle position sensor could be wrong on this. But I'm looking for some more advice. I just recently bought this truck used so idk if that has been replaced before. I know there was a recall on them before. The truck has around 95,000 miles on it. Any help would be greatly appreciated. Thanks.

I have a 98 Silverado z71 with 5.7 350. The check engine light came on giving p0405 code. (low egr voltage). I have replaced the egr and nothing changed. I tested the wiring with the egr unplugged and it tests fine, but if I plug the egr in I lose the 12 volts. If I unplug it I have 12 volt. Now that's with my ohm meter. If I put a load on it, ie hook a headlight to it, it wont power it. I have traced all of the wires back to the ecm. They all are fine. I even unplugged the wiring from ecm and put 12volts from the battery thru the 12volt wire going to the egr and the wire is fine. A friend who is a mechanic by trade said it could be the ecm. I replaced the ecm today.(not a brand new one. one from a used parts/salvage yard). I got the truck to run and the check engine light came on within a few minutes. Same as before, with the ohm meter I have 12 volts going to the egr with the plug unplugged, as soon as I plug it in it goes to 0.03 volts. I even bought another egr thinking it could possible be a bad/shorted one. I'm at a total loss. any help would be great. Thank you!!

Well the saga continues for issues with my 2014 Silverado 5.3 LT Z71 that I purchased in December of 2013. Originally took my truck into the dealer for a flashing check engine light and rough idle along with rough shift from 1st to 2nd gear. The check engine light was a coil that was bad in the number #8 cylinder. Truck only had 9000 miles on it. They said they could not replicate the issue with the transmission (typical response from what I am seeing on the forms.) This whole time having my truck for 9 days. Still have the issue with the rough shift and idle. A week after my truck was returned my door actuator went out on my front passenger side door. After that was fixed another week went by and my front driver side door actuator went out. I took my truck in today because of another check engine light, the truck idling rough, the shift from 1st to 2nd being rough, my seatbelts on both front seats always locking at all speeds (only way to disengage the lock is to completely remove seatbelt), and my usb plug in in my center console not working. My truck has 40,000 miles on it. I was told the check engine light was a bad fuel tank pressure sensor. I was informed since I was 4,000 miles over my bumper to bumper warranty that it was not covered and would cost around $650 to repair even though I have only owned the truck for a little over a year and a half. Left the dealership in a rental as they did not have the time today to diagnose the transmission issue(only after sitting at the dealership for 3 and a half hours only to run the code). So now I am out of my truck again for who knows how long. Both rentals I have had are the same package as mine. Both rentals have not had the issues with rough idle or shifting either. It's ridiculous that I am having all of these issues on a truck that I bought brand new. I bought a brand new truck to have peace of mind that I would not have any problems and frankly all I have had with this 2014 5.3 Silverado is problems(with no answers). Starting to get old real quick. (Side note this does not involve all of the safety recalls that I have had to go to the dealership for. Airbags, transmission connectors, computer reflash etc.)

I have a 2005 chevy tahoe 5.3 ltre vortec engine. about a month and a half ago my wife was driving it and some jack hole parked in front of my house hit her as she was pulling into my driveway. my problem is that ever since the accident the check engine light comes on and goes off periodically. it initially comes on when i step on the gas. but it's not throwing any codes, i plug my OBD2 reader into the truck, nothing. my owners manual says could be a vacuum leak.i've seearched the engine compartment top to bottom and have only found two lines, tested them with a bottle of brake clean, no leaks. any suggestions?

I have a 2003 silverado and it started running rough. when engine is still cold and i take off it hesitates and pops and spits then starts running ok then at road speeds with the rpm in the 1500 to 2000 range it will hesitate for a split second then back to normal. sometimes it will totally stall out. The check engine light came on and i had it scanned and the codes P0100 and P0174 show. I've replaced the MAF sensor more than once, replaced the MAP sensor and even the MAF pigtail. Finally fed up and took to mechanic and he hooked it up to his computer and it shows lean. he changes parameters so it will dump in more fuel and when he did that it still said lean. He has checked O2 sensors, intake for leaks, all plugs and wires and vacuum leaks. I am sure he will get the problem identified but it will probably not be fast enough for me. LOL. so, any clues what it could be? He is leaning towards the computer being bad