5.3 Idle problems

[bigbadchev84]

Just recently since it has gotten cold outside 20 degrees and below, our tahoe has been having some problems. I went to start it the other day and it fired up and died immediatley, I fired it up again and the same thing, I can get it started and give it gas and it will run, After about a minute it will idle on its own, But its up and down in rpms.

It has 83k on it and is the new body style, yesterday I changed out what appeared to be oem plugs, wires, fuel filter, and air filter, Cleaned the map sensor, and throttle body.

Right after all this started I figured it was water in the fuel so i dumped a bottle of prestone water remover in a 1/4 tank of gas and some injector cleaner as well.

I fired it up this morning when i got home and it fired right up and stayed running went right up to 1500rpm then down to a slightly rough 1000rpm then back to 1500 for about 5 seconds then back and forth.

Where should i go from here? No check engine light is on

 

[Jason4x4]

What did you clean the MAF with?

 

[Avery4jc]

Although it's nowhere near the temps you're talking about around here my k3500 did something similar the other day. I disconnected the battery for a while (30 minutes or so) and after that it was good to go. I asked my friend who owns a smog/lube shop if he had any idea what was up and he couldn't diagnose anything, all I know is it works now.
Might be worth a shot.

 

[Duntz00]

pull the vacuum line off the fuel pressure regulator, its on the driver side fuel rail, if gas comes out of the fuel pressure regulator its bad. Same thing my truck did and thats what caused it.

 

[projectfreedom]

My wifes 2003 does that every other month. It will start and turn off. No matter how much gas I give it, or how many times I try to start it it wont stay running. I have to disconnect the battery and connect it right back. It actually tells me when it is going to do it. You know how the radio turns off when you open the door? Well the radio wont turn off no matter what. Ours is right around 90k miles. Never figured out the problem.

 

[bigbadchev84]

I cleaned the MAF sensor with MAF cleaner from napa, The fuel regulator checked out and I sprayed brake cleaner around the intake to check for leaks as well. I ended up pulling the air intake of the throttle body and sprayed 1/3 of a can of throttle body cleaner all around where the IAC sticks though the intake. So far so good, Seems to have solved the problem.