ECU relay.

[Burnie]

Can someone tell me what an ECU relay does. I have been having some intermittent problems with my Mk3 CL and thought after reading some of the threads here I would change the ECU relay and see how it went then, but it doesn't appear to have one.

[Mrk_Mickey]

I'd be interested to know this information as well, as it could potentially be causing a problem in my car.

[Burnie]

The problem I am having is when the car is warmed up and I am driving at a constant speed it suddenly slows up dramatically so I have to accelerate then take my foot off again to try and keep a steady speed then after a while it is all right again and it seems to happen at any speed.

[Bora Sport]

Typical symptom of a failing ECU relay is: - Driving along everything fine when the engine just cuts out exactly the same as if you had turned the ignition off. Roll to a stop. Turn the ignition off, turn the ignition on, start the car drive off. The car will be fine a again for anything between half an hour and sometimes a month or more when one day you will be driving along everything fine .........

ECU Relay, part number 165 906 381. Black in colour, position 3 on the Fuse Box Relay Plate

[Bora Sport]

Sorry my wife has added Skype onto this computer and I don't know how to stop the part number coming up as a phone number. Well it does on my view of the post. Is that the way other people are seeing it.

[Burnie]

I don't think my car has got one, position 3 is vacant on the fuse box relay plate maybe the 1800cc motor doesn't use one, and my car doesn't cut out just feels like the motor has stopped until you accelerate .

[Golf Loon]

Burnie, your car is a CL 1.8. It controls the fuel pump and ecu througght the 167 relay, not the 30 on an EFI car.

Open your bonnet, lean in, see the black air cleaner ontop of the singlepoint unit, that looks like a carby?? Grab hold of the black top bit and rock it left right whilst looking at the black rubber mounting bracket on the base of the unit.

I bet there is a massive split in it, causing an airleak and your issue.

[Burnie]

Thanks for the reply I had a look at the mounting bracket but couldn't see anything wrong with it. I don't know what else to try. It just seems to lose power all of a sudden then pick up again when you accelerate then die again when you back off the accelerator.

[Lams]

Hi experts,
I have a separate problem.
My bro-in-law's '97 GL manual was working fine, then now it doesn't start anymore. It'd crank but doesn't turn.
I use VCDS and no response from ECU, so I check relay 30.
I pulled the relay out, and jumpered it (30 to 87) and ECU comes alive. I'm sure the car would start but its battery's flat
But I'm getting no signal from 85. As I understand 85 should be the signal for relay 30.
I removed the fuse box but can't work out what powers 85 (which is position 1 of relay 3)
can someone with wiring diagram please have a quick look for me - where does it go to at the back of the fuse box?
Thanks

[Lams]

just got a hold of a wiring diagram
85 is earth not signal duhh so I should be looking for signal from 86, which I didn't try today.
Will report back tomorrow - hopefully it is a relay all along