02 5.3 no mods. today it started idling real low like 300 or 400 then it would jump too about 700 then go right back down,throw it in D and it would just about die or would sometimes. dunno wtf made it wanna start doing it all of a sudden,but then tighten the little allen bolt on throttlebody and it idled it up too 500 and been doing fine since i did that. what could be causing that too happen? thanks

-kyle

 

perhaps the idle air control has carbon on it...when was the last time you've done a tune up? did you just fuel up before this started to happen? when did you change the fuel filter last? FPR?

 

havent done a tune up in a while i guess really since i put n2o on last year. fuel filter i've never changed it since i've had it and thats almost 2 years now. and no i fueled up thrusday and it started today... i know its got a knockin in it when i crank up and then it goes away once it idling back down but it sounds like its in the bottom end,which i know thats not got to do with the way it started doing today.. still got the ngk tr6's in it

 

iac valve would be my first thing to check,just unplug it first and see how the idle reacts..

 

Yea, I'd try cleaning the throttle body and IAC as a good starting point...

 

start there yes, but if that doesnt work i would replace the fuel filter. what kind of gas do you use and from where? you might have gotten some crap from getting gas and it got sucked through the old fuel filter. idk

 

chick the dtcs it would help u ...???

 

just 87. and just verys really on were.. it started doing it again today and went completely dead going through the parking lot 3 timesi was ready to set that bitch on fire!!!!!!!