ISV stabilisation current measuring

Duffy3074 · 21-02-24, 10:13 AM

http://www.sealtd.net/quattro/ishamr...rent-lead.html

Morning!

Anybody know the exact wiring layout for one of these?

Is it just a split in the positive side bridged by a multi-meter set to read current?

Thanks!

BackintheFold · 21-02-24, 10:31 AM

>Is it just a split in the positive side bridged by a multi-meter set to read current?
Yes, at least that's how I did it. The original lead was looking a bit old anyway, so I soldered in a longer lead and tried to get the idle right while the bare wires were accessible.

I also bought a cheap Chinese rev measuring gauge to get an accurate RPM. You wrap a fly lead around the main HT lead.
(this kind of thing from eBah Digital LCD Engine Hour Meter Inductive Tachometer Gauge For Car Boat Motorcycle )

It gives various ways to take the reading for 4/6/8/12 cylinder engines....

IIRC, the numbers I was looking at for around 900RPM were around 4500. So it was obvious I had to divide by 5.

Those numbers may be wrong-its been a while-but the "divide by" number is obvious once its set up. (EG if it reads 4500 and is idling just a little slow, its not "divide by 4" to give 1125RPM, or divide by 8 to give 562.)

SorenR · 23-02-24, 05:01 PM

Well, my NG engine (1992 Cabrio with 2.3E KE-Jetronic) also have this gizmo. It's ON/OFF, nothing is really spinning inside.

Actually there are two different types. The one I have is a piston that open or shuts longitude wise to allow more or less air through the ISV, the other type has a turning valve that does the same - still an ON/OFF valve.

I had issues with failing idle at lift-off. Resolved it by putting the ISV in a bag with brake cleaner and a good shake and left to soak 10 minutes. Cleaned it all out with plenty WD40 and a full squirt of sewingmachine oil.

Car has done 330.000 km and has done 210+ km daily since October 2023. Runs about 16 km/l mixed city/motorway.

Duffy3074 · 23-02-24, 11:04 PM

Thanks guys, I’ll bodge something up

:-)

21-02-24, 10:31 AM	#2
BackintheFold Senior Member Classic Audi Club Member Join Date: Feb 2019 Location: Near an MB ur Quattro Posts: 1,191	>Is it just a split in the positive side bridged by a multi-meter set to read current? Yes, at least that's how I did it. The original lead was looking a bit old anyway, so I soldered in a longer lead and tried to get the idle right while the bare wires were accessible. I also bought a cheap Chinese rev measuring gauge to get an accurate RPM. You wrap a fly lead around the main HT lead. (this kind of thing from eBah Digital LCD Engine Hour Meter Inductive Tachometer Gauge For Car Boat Motorcycle ) It gives various ways to take the reading for 4/6/8/12 cylinder engines.... IIRC, the numbers I was looking at for around 900RPM were around 4500. So it was obvious I had to divide by 5. Those numbers may be wrong-its been a while-but the "divide by" number is obvious once its set up. (EG if it reads 4500 and is idling just a little slow, its not "divide by 4" to give 1125RPM, or divide by 8 to give 562.) __________________ 2014 S3 (daily drive) 1987 MB ur Last edited by BackintheFold; 22-02-24 at 10:24 AM.

23-02-24, 05:01 PM	#3
SorenR Grown up member Join Date: Oct 2010 Location: Vesterlyng/Föllenslev, Denmark Posts: 563	Well, my NG engine (1992 Cabrio with 2.3E KE-Jetronic) also have this gizmo. It's ON/OFF, nothing is really spinning inside. Actually there are two different types. The one I have is a piston that open or shuts longitude wise to allow more or less air through the ISV, the other type has a turning valve that does the same - still an ON/OFF valve. I had issues with failing idle at lift-off. Resolved it by putting the ISV in a bag with brake cleaner and a good shake and left to soak 10 minutes. Cleaned it all out with plenty WD40 and a full squirt of sewingmachine oil. Car has done 330.000 km and has done 210+ km daily since October 2023. Runs about 16 km/l mixed city/motorway.

23-02-24, 11:04 PM	#4
Duffy3074 4 ring whore! Classic Audi Club Member Join Date: Aug 2015 Location: Dalgety Bay, Fife Posts: 2,145	Thanks guys, I’ll bodge something up :-)