1983 Audi Sport Quattro ECU

[TechGeek]

Hi all,
So a customer has wheeled out their shiney Sport Quattro and the Tacho is on the blink, the technician who was working on it believes the output from the ECU has failed. Anyway...

Do any of the Audi history geeks know what ECU ran in these road going versions?
Can anyone point me towards a pinout for the unit?
Are there any UK specialists who know their way around the internals of these eighties ECU hardware.

I'm quite happy playing with motorsport ECUs and microelectronics but since this historic car still runs, I'm not super keen on chasing a tacho fault and killing the ECU..the base car holds reasonably good value these days.
thanks, J.

[Olas]

Single coil and distributor? The tachometer is driven off the pulsed earth on the coil.

Coil on plug and crankshaft/camshaft sensor type engines use ecu driven tachometer

[Trev450]

A close friend found himself in a similar position with his Sport a few years back and Keith Murray at Dialynx sorted it out for him. https://www.dialynx.co.uk/

[Deckert]

Yes Dialynx would be my first port of call

[TechGeek]

Blimey...Keith is a great call, I used to deal with him almost 20 years ago!
Thanks Guys.

[Adrian E]

Also Kim Collins at Quattro Sport Tuning in Haywards Heath (although I think he's behind the scenes these days) - I believe he still has his red Sport Quattro, and these were his bread and butter back in the day

[Novexx]

Think it uses LE-Jetronic & that the ECU isn't involved at all.

[annodomini2]

Novexx said:

Think it uses LE-Jetronic & that the ECU isn't involved at all.

LH-Jetronic according to Wikipedia

[TechGeek]

Customer has forwarded a picture and it look single coil... I'll try to get down there this coming week and hopefully its just a signal direct from the coil.
It could well be an issue with the dial in the dash rather than the signal to it. Need to have a poke about under the bonnet. J.

[Olas]

I told you on Wednesday that it was a pulsed earth from the coil

[TechGeek]

To be honest Olas, I still dont know 100% what it is, that is why I asked the customer for a photo. I was not disputing your claim but until I see this vehicle for myself I remain open to ideas. Others have suggested some potential ECUs, the unit I have on my bench certainly looks a good match for some of the pinouts and some of those (if they are correct) may indicate a tacho output... the community input has certainly helped but I've been in this game long enough to never be 100% confident until I've bottomed the job out for myself, there is always that weird prototype, one off barn find, that defies all previously known information!