John Speake

Let's see if he can be more specific....

scottzj

Sorry, the surging is at idle with no throttle. It surges so much that it kills the engine (sometimes). The surging goes from 0-2k rpms during the entire time. I can hit the gas and it revs out nicely but once I let off, it either dies or goes into a surge frenzy. Let me know if I need to give more info, as I am far from a mechanic and willing to help anyone helping me.
Thanks

troy928

Scott,
I had the same thing your are describing on my 89 s4. After replacing both fuel pumps (my car has 2 yours has 1) still idle hunting and very poor performance. I put my LH and EZK in a friends car and my ECU's checked out ok so I called Rger Tyson at 928s R US and he hooked me up with a new rebuilt MAF, Now the car runs perfect. Did your LH and EZK check out ok on a donor car?

soontobered84

Maybe the TPS is misadjusted...or the throttle cable is too tight which is not letting the TPS work properly?

AO

Sure sounds like a false air leak, but could also be a bad MAF.

John Speake

Agreed , if the surging is that extreme :-) I would think closed throttle switch is OK, otherwise the ISV loop would be hunting around.

Scott, try and borrow a known good MAF, or get it checked out on a calibrated test jig, like Louie's.

scottzj

Will do guys.......maybe I can sneak over to Daniels house and steal his MAF for a few. If so, I shall be sending mine off to someone for repair....is shipping a MAF over the pond costly? hehe

John Speake

Louie Ott is in OR and holds stock of my rebuilds.....