Long story short.........I have been running the stock '00 Si ECU since the car was purchased.
Two or so months ago I purchased a OBD2 to OBD1 conversion with a P28 Chipped from Mr. Vega (Great Guy BTW), I installed the ECU and felt the gain instantly but had a small issue when first starting the car from cold, It had a very rough idle until the motor was warm....Then went back to normal.

Now we go back two weeks ago from today.....................Monday I started the car in the morning and it didn't want to turn over right away, I looked at the gas gauge and it was almost showing empty (car was on a hill).

I started to leave for work and everytime I came to a stop sign or intersection the Idle would LOBE from 450ish to 2200 until I gave it gas....Then it would drive normal.

Today while sitting at a light (feeling embarased) on my way home from work...The car idled so low that it stalled.
I started it back up and the Idle was lobing extreme again.

I was listening for any sign of vacuum leak but I can't pinpoint what's what.
I quickly disconnected the Vacuum line running to the FPR and the lobing idle stopped!!!!
the car ran at around 1700rpm (obviously) but no lobing anymore.

Any suggestions to what my problem may be?
It also seems to act up more when the weather is warmer (less in the AM and more in the PM).

Could Someone that has maybe had some experience in this set me in the right direction .......

Thanx

 

Seems like your having intermitant idle issues.

Try adjusting your idle set screw on the top of your throttle body (flat head bronze)

If you adjust the idle too high it will idle hunt, too low & it will idle like poop.
Have you adjusted your ignition timing recently ?
Is it at 16.5 deg at idle ?

Thanks,
John Vega - Phearable.net

 

My Bad, It was after 10pm and I didn't want to interrupt your Pimpin
Anything happen with the Audi this weekend?



Thanks!
I'll try that tomorrow durring my lunch break and let you know if the issue cleared up.

-Jeff

 

Jeff,

Keep me posted

 

Will Do

 

I finally got some time to fiddle with the Si and did all of the things you suggested, But It Still Runs Like POOP.

Think it could be a Plug/Wire Issue?
Even when the car is warm.....It still has a hesitant issue.
When I first started the car (Cold Motor) this afternoon to go home, It was missing baddly...even when I was revving to 3K I could hear the motor missing.

Any Suggestions now?

 

Have you tried swapping back to the stock ECU?