5.3 engine miss?

[Walleyehooker]

I have a 2002 Suburban with a 5.3 and when I start it up cold lately it has a definite miss and has even died out a time or 2 till it warms up some. After driving it a little and gets warmed up the miss goes away and runs perfect. I had a check engine light come on the other day but went out a day later before I could get it scanned. Any ideas? Coil Pack? Has around 115K miles on it.

[Macgyver55]

First thing to do is get the code checked and see what code it has. The code will still be in the history even if the light went out. If it were a coil it will have a specific cylinder pointed out by the code. If it is a lean code it's possibly an intake gasket causing a vacuum leak. Without a code we can only guess.

[Walleyehooker]

Thanks Ill have to get it scaned and see what turns up. If its the intake gasket its going to have to wait for much warmer weather before I tear into it.

[Jeremy airjer W]

My magic ball says P0171 and P0174.

[Walleyehooker]

Cleaning the mass air flo or an o2 sensor would be a lot easier than a intake gasket. Ill try to get a code pulled tomorrow.

[Macgyver55]

The intake gasket is pretty easy on a 5.3. It's a dry intake so there is no need to even drain the cooling system and no distributor to deal with. By the symptoms you gave this is what I think it probably is. We'll see once you get the codes read!

If it turns out to be the problem, you may want to think about checking and/or replacing the knock sensors and harness if they are corroded.

They are located under the manifold.

[Walleyehooker]

I already checked it out on u tube. Doesn't look like to bad of a job. But now Im hoping its a few squirts on the MAF which causes similar problems.

[Walleyehooker]

And the code is...... P0171 Pulled the MAF and gave it a few shots of cleaner and put it back together and started it up and check engine light cleared. Hope it stays that way. Running smooth now but it does when its warmed up so will see how it runs on start up in the AM.