throw me a frigg'n bone here!

[28Marcos]

had this ugly idle/ ugly start/ poor gas milage issue for over a week now...what gives:

pluggs are all good, throttle body clean, air filter new, mass airflow clean, new gasket on egr valve (old gasket was stretched and flimsy), throttle positioning sensor is about a year old. next step will be a new fuel filter/ clean the throttle body sensors with cable cleaner spray.

symtoms:
under cold starts engine rev's to 3g!!!!
under warm starts engine rev's to 1500!!
car used to idle at 500rpms now it idles at no less than 750rpms!
idle occasionally spikes at red light regardless of tranny (a4) being in neutral
under normal acceleration from a stop, car hiccups!

this reallly sux
thanks for your help ls1!

[bigrondownhiller]

check for vacuum leaks.

[0rion]

check the pcv hose going into the passenger side of the intake. Sometimes on the back side of that hose it will rub a small hole or crack back there. Just something to check. Definitely sounds to me like un-metered air coming from somewhere. Not sure if you have a propane torch(unlit of course) or something but just use the propane and go around all the hoses and see if the idle changes. That'll tell you if you have a vacuum leak somewhere.

[PFM]

check the pcv hose going into the passenger side of the intake. Sometimes on the back side of that hose it will rub a small hole or crack back there. Just something to check. Definitely sounds to me like un-metered air coming from somewhere. Not sure if you have a propane torch(unlit of course) or something but just use the propane and go around all the hoses and see if the idle changes. That'll tell you if you have a vacuum leak somewhere.

WD40 works very well for finding vacum leaks.

[28Marcos]

but i just got the computer scanned and it thew a few codes

P0102: MAF or VAF A Circuit low input

P0171: Bank 1 system too lean

P0174: Bank 2 system too lean

P0507: Idle control system RPM High (pending)

The egr gasket made a difference but i think i found the leak on that egr alumimun hose hopefully autozone has one of those!
think that could be the culprit to all these codes

[TXTOYS]

check the pcv hose going into the passenger side of the intake. Sometimes on the back side of that hose it will rub a small hole or crack back there. Just something to check. Definitely sounds to me like un-metered air coming from somewhere. Not sure if you have a propane torch(unlit of course) or something but just use the propane and go around all the hoses and see if the idle changes. That'll tell you if you have a vacuum leak somewhere.

what he said mine had a hole in it big enough to stick a finger in. made it run like crap

[28Marcos]

yea i've replaced that part twice since i've had my car lol recently used heater hose on it this time lol

[2001NBMZ28]

One thing all those codes have in common is a vacuum leak, especially 171 and 174 at the same time. You can look them up individually for your year at gearchatter.com

[Y2KArcticSS]

I had the EXACT same codes, EXACT same problem, it was a vacuum leak. Even a small hole will cause that. I put a new hose on, ran fantastic instantly, and codes went away by themselves.

[28Marcos]

hmm...well i did the wd 40 trick and no change in nothing...readjusted the egr aluminum hose and obvious air leak went away, car now idles at 600rpms, engine light still on, and the ocassional spike at idle...


ps where is the VAF?

[2001NBMZ28]

Don't know what VAF stands for, maybe volume air flow or something? P0102 on our cars is MAF sensor circuit low frequency.

[28Marcos]

i figured it out!!! i think, well after work i went to the bar, drove to another bar and noticed no ses light or an ugly idle! hallleluha! (dont' think i spelled that right) but yea ran like a champ tonight, well see in the morning, all i did was adjust my egr hose it was sort of crooked lol that but i think my car just wanted me to chillax and have a beer lol

[0rion]

if un-metered air was getting in there then that was your problem. Glad you got it worked out.