Idling issues!?!

[Blackie]

Ok, my ADA engined (1.6) 80 sometimes doesn't want to idle.

It was/is having problems running on regular grade fuel, only runs without hesitation on super.

I have replaced the dizzy cap, rotor arm, spark plugs, knock sensor, both the temperature sensors and still no joy..

Do these cars have an idle control valve or something similar?

[missfire]

There can be a problem with the Relay for the ECU, it lives under the dashboard, above the drivers feet.


The soldered joints on the circuit board go bad, resoldering fixes it if this has happened. It may not be your problem, it usually causes misfiring at speed and cutting out at idle.

cut this from..this! (not ada though i know but not far off it)

http://www.audi-sport.net/vb/classic...e-problem.html

read about the isv being in the airbox too..but...sounds a strange place to put it

http://www.audifans.net/ftopic-8099-...orderasc-.html

[MadderThanMax]

It may just be as simple as a vacuum leak. Buy a can of Carb Cleaner and spray all around your hose joints if the idle increases then you've found your leak and of course your unstable idle

[msh]

Originally Posted by Blackie

Do these cars have an idle control valve or something similar?

Every car with fuel injection has ISV or stepper motor, which opens throttle as needed for idle - later usually for SPI. Since ISV redirects air around throttle, it's not hard to find it.

[Blackie]

Originally Posted by MadderThanMax

It may just be as simple as a vacuum leak. Buy a can of Carb Cleaner and spray all around your hose joints if the idle increases then you've found your leak and of course your unstable idle

Tried that already

It's not an unstable idle, it just stops sometimes, will start again no problem, idle speed seems to be around 1000-1100rpm

[Blackie]

Originally Posted by msh

Every car with fuel injection has ISV or stepper motor, which opens throttle as needed for idle - later usually for SPI. Since ISV redirects air around throttle, it's not hard to find it.

So where is it?

[msh]

Originally Posted by Blackie

So where is it?

Usually somewhere around cam cover. Because I can't find quickly ADA pic in internet [but I'm not surprised why ], here's a couple examples.


This is ABK and ISV is that thing situated above cam cover, connected with intake manifold, with electrical connector facing front.


And here's AAD, ISV is in rubber mount at the rear of cam cover.

[MadderThanMax]

Originally Posted by msh

Usually somewhere around cam cover. Because I can't find quickly ADA pic in internet [but I'm not surprised why ], here's a couple examples.


This is ABK and ISV is that thing situated above cam cover, connected with intake manifold, with electrical connector facing front.


And here's AAD, ISV is in rubber mount at the rear of cam cover.

On the top photo the ISV is located DEAD CENTRE of the picture lying on top of the cam cover and to the right of the inlet manifold. (It s black and has for chrome bands to the left of it)

On the bottom photo its silver and located at the back of the cam box.

[MadderThanMax]

Originally Posted by Blackie

Tried that already

It's not an unstable idle, it just stops sometimes, will start again no problem, idle speed seems to be around 1000-1100rpm

Sounds like the valve has failed. Your idle is on the high side, it should be around the 850 mark.

An operating ISV increases the cars idle on start up the closes adjusting the Idle to 850ish. You may get away with cleaning in Carb cleaner and working the door on the valve in 3 & 1 oil. then retry. Failing that its a new valve I afraid, and they won't be cheap.. Some of the old ISV's used to overlap with BMW which in the case of a 88 7series was £64 from GSF! fingers crossed you get lucky!

[Blackie]

Thanks folks, would this cause the hesitation at around 2200rpm by any chance?