DPR Fuel Cut-Off problem

["Alexander van Gerbig" <Audi_80@email.msn.com>]

    After getting the timing done on the 80 I noticed an idle problem.  I
hooked up my DPR current meter and duct taped it to the hood so I could see
it while driving.  I revved the engine in "N" and when the idle drops I
watched the negative current drop the plate quickly as it should, but when
it comes down quickly after a hard rev the idle will drop, stabalize, then
dip below idle, then pickup.  I watched the current and figured it out to a
degree.  When the fuel cut-off happens the negative current is way
over -40mA, -70mA sometimes.  The air flow plate drops properly, but when
the current goes from negative back to idle(0-5mA) there is a current surge
above 5mA which causes an idle surge.  I assume that is there to counter act
the negative current dropping the plate quickly so the car doesn't stall.
This is also the cause of the surging that has plauged my car since I bought
it.  I drove in 1st gear and watched the current as I coasted down from
3,000rpm.  As it should the fuel cut-off works, but when it comes back to
positive it surges casuing the idle to surge at 1,500rpm everytime I slow
down in gear.  So maybe time to get a used DPR and swap?  ECU problem?

Thanks!

Alexander van Gerbig
'88 Audi 80 -- Koni Yellows, G&M Springs
HÖR Technologies Sport Hydro Cam, K&N Filter
Borbet Type T, Dunlop SP9000 Sport

The Audi 80 Pages------------------
http://surf.to/the80pages.com

German Parts Importing------------
(914)-232-7467

Katonah, NY 10536