2002 5.3 Tahoe will not idle

[AndyL3]

I cannot find reference to this in the discussions, but excuse me if there is already an answer somewhere....
My 2002 5.3 Tahoe recently would not start and idle. If I opened the throttle it would run, but died when throttle released. I disconnected the battery ground and the problem cleared for 4-5 weeks and the truck ran perfectly. Came back today and cleared again with the ground disconnect. I have replaced the IAC valve maybe a year ago.
Any thoughts.?

 

[Marky Dissod]

Vehicle AntiTheft System (VATS)? That's how I remember defeating it ...

 

[Joseph Garcia]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

I cannot personally assist you with your issue, but other members of this Forum much more knowledgeable than me in this area will chime in.

 

[Fless]

One thing you could do is to look for a vacuum leak using an old school vacuum gauge, and/or unlit propane around the engine compartment to see if the engine runs better at any given spot.

Have you looked at the fuel trims at idle (as much as you can get it to...) and at 1800 rpm? If so, post those up for us to see.

See what the MAF is reporting at the lowest possible idle it can hold. It should be approximately the engine displacement in liters, in g/sec. (5.3)

 

[AndyL3]

OK thanks I will borrow a scanner and try to get some readings. I could post some photos but it is a fairly plain grey daily driver - nothing spectacular...!!!

 

[Scottydoggs]

check engine light on yet? if so scan and post the code.

 

[AndyL3]

No the check light has never illuminated. Trying to get a scanner to check codes/values.