I have a 2005 Isuzu Ascender which is a little different from the GM models I think. Mine has no MAF and no Reduced Engine Power light on the cluster. I had a bunch of codes and I fixed them all including a P0014 which I cleared by cleaning the VVT solenoid. I had two bad coils so I replaced all six. I have no misfires, no codes, engine starts and idles beautifully but has no power when driving. Throttle body was cleaned, throttles opens fully on ignition but restricted to 2500 rpm with engine running. Timing is fluctuating on idle and pegs to 25 when accelerating. Fuel trims are ok, but both upstream and downstream O2 sensors have the same waveform/signal making me think its a clogged cat and/or I need a new VVT solenoid.
That’s funny, because I was looking through the comments to see if anybody else noticed that it’s not a V and it’s actually in line anyway thanks for the video I’m trying to get mine to run again, rough idol, sometimes I can get it started and then it will rev like extremely high maybe one or 2000 RPMs above necessary, out of control. And then eventually after running it for like 1020 minutes it will relearn and then run perfect, as soon as I turn it off for a bit, it struggles to start again and it’s just being a total bitch. Anyway trying to figure out if the vacuum line is actually the problem or if I got a computer issue or maybe a coil pack or throttlebody sensor, but I just put a new throttlebody on.
I cleaned out my throttle body with cleaner and then had a very rough idle. I took it to my buddies house who had an advanced scan tool, punched in idle relearn, and it ran perfectly. It only took two minutes. My simple scanner did not have idle relearn ability.
U can also manually force it into a relearn by unhooking the battery for 15 minutes and plugging it back in then driving it consistently for about 30 minutes going onto the highway etc….it’s impossible to find someone who will do a scan tool relearn around my area lol…jerks
With the Envoy & the Trail Blazer from 2000 and up, you can't just disconnect the battery completely. Only disconnect the negative never both positive and negative. Because then it not only clears out the codes, but it also clears everything else out. your car basically has to learn how to idle again I found this out the hard way.
Same lol. It made multiple parts on my suv fail and I had to change out bunch of things. They make a thing I think it's called a computer memory saver. You plug it in to you voltage cig lighter port and it keep your comp alive when battery disconnects. The worst part is it doesnt even tell you this in your drivers manual haha.
@@jonathynfranklin8847 to fix idle relearn the way to do so is to put car in drive with parking brake and your foot on the brake until the computer learns the right idle. Sometimes takes 5 minutes sometimes takes 15. It sucks to do
Yo I have a2003 GMC envoy. Did the 5 cylinder is misfiring. Went to the store ran great. Got back to the car to leave it has this crazy rough idol. I'm bout to replace to coil starter and plug. What are you saying to do that might fix it.
@@charlesterrellii7592unless u know someone with a scam tool to make it relearn with the new parts, u will have to do the hard relearn by unplugging the battery but the things ur talking about might not require it..,it’s a trial and error thing I guess lol…mine didn’t have any issues after replacing the coils but did when I replaced the vvt solenoid
If you disconnect the battery, the idle learn is cleared. After reconnecting battery, it will run awful but after driving a few miles it will relearn by itself.
No it's NOT. Envoys and TrailBlazers ran speed density systems until 2005. 02-04 have no MAF and use Map sensor for fuel metering. He did in fact change the IAT sensor in this video.
Had the same issue and turned out to be faulty MAP sensor and just cleaned the ATS with cleaner and end of problem. Also get AC Delco parts and beware of off brand components.
Hmm I think you might have saved me money. At first I thought it was the maf sensor. Then i seen it after taking hose off. I cleaned it with maf cleaner thinking it was the maf at the time and my tb drove fine for 3 days but then went back to being rough. I'm going to replace this first before trying anything else.
@@codebreakakelley2916It seemed to run better for a while but gradually got worse until it started to stall. i changed the spark plugs and ignition coils. i also opened fuel line and pumped carb cleaner and ran engine on carb cleaner for a little to clean fuel injectors. runs much better now.
I have an 05 Envoy 4.2 that bucks when I first start it & then it idles fine but after about a minute I hear a funny vacuum pop. After about 15 mins of driving it stalls when I'm stopped at a red light etc. Anybody here have a clue??? no check eng light either.
@@Lifegoeson-nv9jv Thanks for your reply, I replaced the belt tensioner about a month ago. I think I figured out where the vacuum pop noise is coming from. I think it's the Secondary Air injection Check Valve. I ordered one on ebay for $48.00. It has something to do with injecting air into the exhaust manifold for 30 seconds when you first start the motor. I think the check valve is stuck closed. Will keep you posted after I get it. Thanks again.
My trailblazer does all that and it says cylinder 4misfire but my breather hoses are dry rotted and cracked could that be the biggest problem with it no connection from the breather
Was it also using alot of gas y it was saying it was still to lean because that's what's happening on myn is its using 30 a day in gas wen the same running of the other on I have before Trans went out was 10 a day in gas I'm just wondering it that is what's going on with myn
