I'll definitely keep that in mind. I'm an old man when it comes to loudness. It's not a muscle car, it's my daily so I want it quiet. Gonna look around for something that flows good has a good tone to it and is quiet in the cab. If you have a suggestion please let me know! All of this will be after I get the tuner to look at it. If I take it to him with modifications he'll charge me for a new tune. I just want him to make it run properly. I plan on purchasing HPTuners this fall and starting to toy with it here and there.
There's definitely improvement to be made if I were to do full exhaust and headers, but that's not in the budget. I have no doubt though that this truck should make good power on the stock exhaust. The one thing that I do think could be a possibility is my catalytic converters could be either clogged or broken inside causing them to not flow correctly. They do make noise. Kinda like gravel being shook around in a tin can to the tune of the idle of the truck. I'm torn between cutting them off altogether or cutting them off and replacing with an aftermarket Cat. I don't really want it smelly all the time, and I do live in an emissions inspected county, though that portion of the ECM is tuned out it appears on my last inspection report. The upside would be I don't have to spend the money on the new converters, and potentially more power to be had without them. As far as it being slow, I definitely know what you mean. I've watched videos of this year model a lot though and the consensus is that my stock pulls look the same, but the pulls after the tune and cam should definitely be better.
Seems pretty spot on to me. Thank you so much for that resource Jglew82...I'll be revisiting the tuner in a couple of weekends. I wish it wasn't an endeavor to get to him, but he's over an hour away and through a chunk of Houston. Not really where I want to drive with a truck that throws a fit, but I also want to bring it to him hot and experience the fix after he's fixed his business in the tune. So we'll see how it goes I appreciate all of your responses. I'll take a look at injectors too. Past research no one has mentioned injectors with a mild to mid cam, but searching specifically for duty cycle like you mentioned leads to stock engines reaching 90% which means yes they are most likely tapped out by the time I get up in the rpm range. That thing has to be sucking some fuel through there. That will likely be a project for down the road though as it would require a re=tune and not just a free patch up like this time will be. I plan to purchase hptuners and the MIVP2 and start toying with it myself later this year. When I went in there I strictly asked him to make the truck run the best it could with the upgrades it had which is only the cam.
The truck does sound good at higher revs! Especially for the stock exhaust. I’ve definitely considered that, but something is for sure wrong. Once in a blue moon I will feel it pull like it’s supposed to and it’s night and day difference. I’ve been researching hptuners and think I might have figured out the problem, but no way of knowing without visiting my tuner. when I watch live data, I can see the truck pulling timing doing a brake stand. So much so that it dies when I get off the throttle.
So I have a 2003 Silverado 1500HD. I put the Brian Tooley Racing NSR cam in. Otherwise the whole truck Is stock. Mechanically in good working order besides the issue I"m about to explain. I got a Wideband tune done by a tuner about an hour away from me that is very reputable. The truck seemed to run pretty good right after the tune was done, but now that summer is in full force it's almost undriveable. I can't tell if it's actually the problem with the tune or if I'm missing something. I've taken several videos that explain and show the problem first hand. The first video I'll link has live data of a brake stand followed by a short acceleration burst. The truck just seems lethargic when taking off, absolutely can't spin tires from a dead stop the most I ever get is a little chirp, but if I shut it down the truck can't find idle and dies most of the time as shown in the video as well. Adding to that, occasionally I will get either detonation, or backfire through the intake. I can't tell which it is but it sounds like someone is hitting the firewall with a hammer followed by completely no power for about 5 seconds. My next question would be does it seem like torque management is still in full force on this truck? This thing is a slug from a stand still. I can't hardly spin tires from a stop even on damp pavement. Even if I brake stand on slick pavement it struggles and seems to dip in RPM's shortly after tires start spinning This video below has a before and after cam 0-60. When I took this it was the day after the tune. That's honestly the most wheelspin I've ever gotten from a stab. I know the truck has it in it because at 60 when it shifts to 2nd it will chirp the tires most of the time. I know big cams tend to lose low end power, but this is excessive. Plus I've seen plenty of trucks with this same cam perform way better off the line. I hope these videos help explain my problem. My main question is should I blame the tune, Was something not done right? If you can think of another problem I'm overlooking I'm all ears Things I've checked so far... Vacuum leak (none found), Fuel pressure 55PSI with 3 psi dip at startup quickly recovering to 55, Plugs and wires only have about 15k miles on them, MAF is clean, Air filter is clean, O2 sensors are good, The only thing I'm going to check soon that I haven't is catalytic converters. They do make some noise, but I felt that if they were clogged top end power would suffer more than it does.
So I had a transmission guy look at my truck and drive it. He connected a Matco Tools Maximus 2.0 diagnostics tool. He confirmed that shifts were all good, and TCC was unlocking and locking as it should. He is pretty convinced that I have a bad MAF. My tuner said that it is throwing the code because the truck does not know how to idle properly with the new cam. So he suggests its fine to drive up to see him for the Wideband tune. What I need to figure out now is if I need a new MAF or if it really is a value that needs to change for the MAF to read properly. I have images of the live data values that I'll upload. I'd love some help deciphering it. IAT Values look good. IT's been hot here so I looked for low temps first off, but it normally reads about 99-110 degrees. It's been about 98 here lately. At idle MAF values show an actual value of around 1.513 lb/min. MAP values are 21.0 in/hg. Short range fuel trims and long range fuel trims show a high negative value of about -18 to -22 when warm. When cold a different story. I will say fuel economy has been horrible. About 8.8mpgs on the last tank of 200 miles. I averaged about 12-13 before the cam and tune. I haven't even been able to drive it hard so there's no excuse for the poor fuel economy except that I guess the tune is causing it to run extremely rich. UNLESS...I actually do have a bad MAF sensor causing it to overfuel like crazy. The guy tuning my vehicle has done thousands of these engines, and had personal experience with this exact cam several times. So much so that he sells this cam in his shop. No doubt in my mind he knows what he's doing. I'm trying to decide if I want to drop $80 on a new MAF or drive the truck up and get the tune finished before I do that. I should mention. His shop is almost 300 miles from me which is why I'm contemplating. If he was right down the road I would make no question about it.
I’ve unplugged the battery a few times. Even held leads together for 30 seconds to clear the computer but if the truck is warm it fires up and drives the same exact way. I disconnected the cooler lines, but didn’t remove them from the truck, it’d be impossible for me to have swapped the lines accidentally mainly because they’re solid aluminum lines all the way up to the radiator cooler.
Any ideas on the TCC Lockup in reverse? Also I was thinking limp mode with these transmissions was 2nd and reverse only, unless there's a couple of different ways it could respond. So I checked the wiring harness yesterday and nothing seemed out of place, all was plugged in good. Only wire I've had issues with was a dark green wire that goes into the harness on the park/neutral Solenoid. It was broken before I took the transmission out so I fixed it, but then started having all these issues, so I cut it again thinking what the heck. Didn't seem to change my scenario. I'll fix the wire again and make sure I have a good connection though I don't think it has anything to do with my issue. Looking at diagrams shows its for the park/neutral location of gear shifter. I'll look around and make sure I didn't miss anything. Would I not have MIL Codes for transmission though if something was unplugged or plugged in wrong?
Hey guys, new to the forum. I signed up to try to get help with this problem. I'm always looking around to see if I can find good info here. I own a 2003 Chevrolet 1500HD. As you guys know it has an LQ4 4l80e transmission and 3.73 gears. I recently put a cam in the truck and dropped the transmission to change the rear main seal oil pan gasket and some other gaskets. I put it all back together and I'm loving the idle of the cam, but I'm having some pretty serious transmission issues. I'll preface this by saying...fluid is topped off, still looks red on dipstick. Some fell out of the TCC when we dropped the transmission and it was pretty dark, but didn't smell bad. I have triple check the wiring harness and I haven't found any unplugged wires, also no MIL codes for transmission. Issue #1 it gets hot. I can just be idling for 15 minutes or so and the transmission will get to almost 200 degrees. If I jump on the highway it drops about 10 degrees but as soon as I slow down it jumps back up there. Issue # 2 If I drive it cold I don't have this issue, but as soon as it warms up I notice it tries to take off in 3rd gear with torque converter locked. It will unlock enough to not let the engine stall but as soon as I jump on the gas to take off it lugs the torque converter locked and seems like it's in 3rd gear. I've done 2nd gear starts and it doesn't feel like that. As soon as I give it a little extra gas though it jumps down into 1st and drives normal. Goes through every gear just fine. Torque converter locks and unlocks perfectly fine. Only problem I have beyond the takeoff is its getting to warm for my liking. Warmer than I used to remember. Issue # 3 When I put it in reverse torque converter is unlocked, but when I start to roll at idle it locks the torque converter. This causes the truck to stall sometimes if I jump back on the brakes. If I just let it roll the truck will get up to like 10 mph without any throttle or rpm change. If I understand correctly the torque converter should never lock up in reverse or first gear. Issue #4 I found this out by fluke... I engaged tow/haul mode and the truck will not get out of first gear. I haven't tried putting tow haul mode on while rolling over 30 mph, but even at that speed it jumps into first and unlocks TCC. it'll idle even at 20 or 30mph but as soon as I get on the gas you can tell it's in first. RPM skyrocket till it catches up with driveline speed. I had a tuner flash a mail order tune for the cam. I was going to see him this weekend for a Wideband tune. He said that this funky transmission stuff shouldn't have anything to do with the tune. The only thing that he changed is making gear changes firmer. With that said I'm guessing that's line pressure that he adjusted. I could be way off base here, but Would a weak pump or too low of idle cause the TCC to not unlock, or do these funky things? Truck seems to drive fine above 1000rpm, but at idle is when I have my issues. To answer further questions. I have no Transmission codes. Only MIL I get is P0101 and my tuner said he would fix that issue when I saw him this weekend. I appreciate any help or advice I can get.
Most OnlineNewest Member
Who's Online 83 Members, 0 Anonymous, 1,093 Guests (See full list)
- Tom Cox
- Tyler Cartwright
- Thomas Wilson
- 2016 Sierra Owner
- Paul WK
- Maize & Blue
- Marcel Almeida
- Jeffery McRae
- Marv’s Trailboss 19
- gary weesner
- Ski doo 800