Progressively worsening cold start issue HELP!!!

[diggyd357]

2001 Yukon XL with 205k

I recently purchased this suv for my wife to drive to work, get the kids to school as well as for vacations, etc. All seemed well with it except it was a "cold starter". When we start it up for the first time if the day it spits and sputters then revs REALLY high then sputters etc... Once it's warm it runs great. Also, it seems like the colder it is outside the worse it is. It is getting worse and worse and I'm worried it's gonna leave my wife and kids stranded somewhere one day. So far I have changed the plugs, plug wires, air and fuel filters. I pulled the cel codes and the only one it had was "engine misfire" PLEASE PLEASE PLEASE HELP !!!!!!!!

 

[Screwd up 6]

Sounds like the notorious intake manifold gasket leak. I just went thru this on my truck a few months back. It only happend on cold mornings. It would rev WAY up, then stumble really hard for about 30 seconds to 1 minute. After that, it was perfectly fine and ran great until it sat and got cold outside again. I bought the gaskets and new intake bolts from GM and did the install in about 4 hrs (taking time to clean parts and not rush anything).

Check out this link. Also, why you are there, you mine as well change out your knock sensors if you never have before. Really is not a hard task to do, just take your time and you can save yourself a lot of $$ doing it yourself.

http://www.agcoauto.com/content/news/p2_articleid/193

 

[mikemedic3]

That is sounding like a intake gasket, but also check your throttle body too. make sure it is clean and not sticking. You can do the brake cleaner on the intake edges and see if idle changes, to check for vaccum leaks, be careful when doing this though! Also if you need the intake gaskets be sure they are the new teal centers, not the orange, they have been upgraded.

 

[mikemedic3]

That is sounding like a intake gasket, but also check your throttle body too. make sure it is clean and not sticking. You can do the brake cleaner on the intake edges and see if idle changes, to check for vaccum leaks, be careful when doing this though! Also if you need the intake gaskets be sure they are the new teal centers, not the orange, they have been upgraded. stupid comp double posted sorry!!

 

[davidmnix]

Sounds like the notorious intake manifold gasket leak. I just went thru this on my truck a few months back. It only happend on cold mornings. It would rev WAY up, then stumble really hard for about 30 seconds to 1 minute. After that, it was perfectly fine and ran great until it sat and got cold outside again. I bought the gaskets and new intake bolts from GM and did the install in about 4 hrs (taking time to clean parts and not rush anything).

Check out this link. Also, why you are there, you mine as well change out your knock sensors if you never have before. Really is not a hard task to do, just take your time and you can save yourself a lot of $$ doing it yourself.

http://www.agcoauto.com/content/news/p2_articleid/193

YEP, what he said. I just did mine in January.

 

[dmperfection]

I had the same issue four years ago on my '02; new intake gaskets took care of my problem and hasn't come back.

Sounds like the notorious intake manifold gasket leak. I just went thru this on my truck a few months back. It only happend on cold mornings. It would rev WAY up, then stumble really hard for about 30 seconds to 1 minute. After that, it was perfectly fine and ran great until it sat and got cold outside again. I bought the gaskets and new intake bolts from GM and did the install in about 4 hrs (taking time to clean parts and not rush anything).

Check out this link. Also, why you are there, you mine as well change out your knock sensors if you never have before. Really is not a hard task to do, just take your time and you can save yourself a lot of $$ doing it yourself.

http://www.agcoauto.com/content/news/p2_articleid/193

Thanks for this link Srewd up 6; great resource. Love the following line:

"Strangely, as the engine warms up, the roughness tends to go away, which seems confusing."

It's elementary, Watson! As the engine warms, metal expands and seals the tiny area that allows unmetered air to infiltrate the intake.

I may redo myself with updated gaskets and take care of knock sensors as well.