My wife has a 08 tahoe 5.3l, I put this engine a little over a year ago. She had an oil change done and the guys got pissed cause she refused to spend $190 on an oil flush and only put 2.5qts in and not the 6qts she needed. So needless to say the freaking blew the lifters to hell and back. I didn't have time to do the engine work so a very good friend of mine is doing it. He tore it down cleaned and checked everything. Put all new parts in it and finally was able to start it tonight and now it is suffering from a cylinder 1 and 2 misfire. He's been at it for 8 hours and can not figure out what's causing the misfire. Can anyone please help me. I had to drop my rental off so now we are down to 1 vehicle and that just won't work. Please someone help me out.
2008 tahoe 5.3l in need of desperate help
- Thread starter Nickct203
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Charles Hughes
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Has your buddy tried to swap cylinders 1 And 2 coil packs with another cylinder and see if the misfire switches? Eliminate a bad coil pack and spark plug first
Yes sir. Tried that. No difference still 1 and 2
Charles Hughes
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How about coil pack wires? Swapped or replaced?
If there was either a different crank or cam sensor installed, then a CASE relearn is in order.
petethepug
Michael
The end is where the simplest mistakes are made. I thought about switching the coil pack too.
Next come swapping the plugs or wires or what Fless said.
Next come swapping the plugs or wires or what Fless said.
New crank and cam sensor with new cam. He said he did the tune for the engine to accept the new parts.
New plugs and wires. The rest of the cylinders are good just 1 and 2. Doesn't matter what *** swapped around the rest still ran good
You could have two bad plugs -- it wouldn't be the first time. Pull, check for carbon tracking or cracked porcelain, and swap them to good cylinders.
Any changes to the injectors? New o-rings when reinstalled?
Charles Hughes
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If the cam is original and the lifters are new then that could be causing it. Lifters wear to the cam.
Im gonna have to run there tomorrow after work and see if I can add some 2 cents to this.
Make sure he did (or does) the CASE relearn, 'cause new cam and crank sensors.
Talked to him this morning he never did the case relearn
It's a quick process -- he should do it just to rule it out. It may not be what's causing the misfire but it's on the list.
First thing we will try when I get out of work. Thank you. If this isn't it I'm really drawing a blank
Marky Dissod
Full Access Member
Typically pcm tuning includes bypassing the CASE relearn so it need never be done again going forward.
That's likely what the tuner meant.
