Dart_SI

iTrader: (1)

car does this randomly, but the idle will sound rough and on the RPD my afr's are hovering around 16-17. (normal is about 14.8).

only thing i can know that could possibly be the cause is that i have a CEL for my EVAP purge solenoid (which i know is bad anyway, hard to start after a fillup)

anybody have a clue as to why im having this issue?

dayhoff35

iTrader: (13)

theres no vacuum on the rpd is there?

Dart_SI

iTrader: (1)

nope. which is why im getting a boost gauge next month.

Chevycobaltss3

iTrader: (2)

Purge valve one. But also cold condensation on maf .

Heat soak, ect

Red_SS/TC

Its the Evap being bad bro. I had the same problem and it went away after I changed it.

Jalake

how is your spark advance at idle?
im having a similar issue

Dart_SI

iTrader: (1)

havent looked since honestly i dont know what to look for on that. other than knock retard.

Dart_SI

iTrader: (1)

sounds like its possible. its been 20 degrees all week (it was 65 a few days ago tho) and i always have loads of frost on my car.

Chevycobaltss3

iTrader: (2)

Many things can cause the spark advance to jump at idle. Maf issue, dal issue , ect.

Frogstofall

iTrader: (1)

It's all those 30psi spikes...

Can you post a video? I know vids don't always pick up everything but might be worth a try.

dayhoff35

iTrader: (13)

I had an issue with my timing at idle also which made it seem like my engine was pulsing, could tell with the boost guage which is why i asked. Changed up my timing at idle and all is well now.

Chevycobaltss3

iTrader: (2)

Yeah I did that with frogstofalls timing before and it still did it.I tuned in lower dals and still did it. So I was like wtf and he sent.me a old file and said this works great. So I put all the **** of the old file to this one and it was fine lol .

Dart_SI

iTrader: (1)

well unfortunently im not getting a retune till i throw on the bnr2871 in march. im pretty sure the problem is my evap purge solenoid since others have had this issue from that.

i need to buy hptuners or something soon. lol.

Dart_SI

iTrader: (1)

Bump. Car did it again this morning. Idling at 16-17 afraid but goes normal if I tap the throttle for a few secs. After I drove to work the idle is now at 14.8 afr on average.

Maybe the cold air? Its been really cold lately.

If it was a vacuum leak I assume it would still idle like poop.

Oh yea, checked my spark advance, it was jumping from 5 to as high as 15 at idle. Now its normal (no higher than 5)

Im confused. Maybe a dirty tb?

vahdyx

iTrader: (7)

Well not sure your altitude, but here in Colorado, it gets cold often, I don't think thats normal. My car on a cold day has an AFR around 14.8

I don't think the weather has anything to do with it, but I'm just guessing here.,

Dart_SI

iTrader: (1)

Its probably just my Damn evap solenoid stuck open. I did more research and I saw that it can cause a crappy idle.

lockdownlegend

iTrader: (1)

its definetly evap related...if ur having a hard time starting the car after filling with gas, then the problem is the evap vent valve located by the gas tank. had the same issue and replaced it and problem was solved. evap solenoid is cheap to so just do both and its less than 30 dollars and i can guarantee your issue will be fixed

SSlobalt

The evap sol being stuck open creates a vac leak, so it makes sense. I think that's a $40 part, right?

lockdownlegend

iTrader: (1)

the parts are pricey. but as i said you can get both for 30 if you take the time to search. guy on ebay sells the purge solenoid for 10 dollars shipped to your door.

and as i mentioned earlier...if its rough cranking after a fill up I can almost guarantee its the vent valve by the gas tank.

Dart_SI

iTrader: (1)

Ill probably replace both. Thanks for the help.