Can someone identify this Relay

[leepox]

Hi, I have been trying to sort out electrical gremlins with my car. After sticking my head under the driver-side dash, I found this relay:

It's connected to the DME loom directly. Search in google has been for naught. What the hell is it?

Also I have noticed that one wire in the DME loom has burnt out, might explain my cars rough idling. About to replace the DME harness but just making sure that I am not just going to burn it again due to a dodgy relay etc. Thanks!

Final Q. What would cause a relay to click non-stop? (this is my power window relay) Guess it's time to buy a new one?

 

[chas3.2]

Ring up your OPC give them the part number they will tell you what it dose.

Clicking window relay is dirty pin switches that bring on the interior lights this relay
is so you can wind up your windows with out the ignition on but doors open.

 

[pauljmcnulty]

This has come up before. Unfortunately two possible answers come up!

A google search suggests it's a relay for US foglamps, but I remember it being linked to the DME circuit before so that makes no sense.. If you google the number you'll get lots of mentions of it, but no conclusive answers.

Could it be a relay that was used for both purposes? Apparently it's a "flasher-blocking relay" according to Porsche, but it's not in PET.

 

[pauljmcnulty]

Scrap that previous reply! It is on PET, but my saved copy is set to 1990 cars for my own one.

If you look it up it's listed on early 944s, as a fuel pump relay. Also linked to a 993.615.227.00 part, which I guess supercedes it?

There's also a note to "refer to technical information", but nothing more. I wonder if that would be a technical notification that the 944 relay is NLA, and the 993 relay replaces it?

 

[leepox]

I am going to ring up my local OPC and have their final say. It seems like this mystery has never been solved by the internets yet!

 

[leepox]

Ok so I did a bit more research as the guy from Porsche can't figure out what it exactly is for.

Found a polish forum and one of the members said " the role of the relay is like electronic choke relay after firing on the car 2min 40sec and sends a signal to the 13 pin kompa and increase the fuel-air mix" but this is a direct quote from google translate.

Also it seems like this has been discontinued and the newer DME relay incorporates whatever functionality this relay had separately. Or something along those lines. Makes me kind of paranoid given how I am idling pretty rough at the moment.

 

[Eldavo]

I wish I had a 13-pin Kompa

 

[pauljmcnulty]

Ok so I did a bit more research as the guy from Porsche can't figure out what it exactly is for.

Well, he should look at his own computer! [&o]

As I said above, it's on PET, listed as a "fuel pump relay", but superceded by the part number 993.615.227.00. This is the newer (993, of course) DME relay that he should have under the counter.

If the Porsche guys can't read their own screen it's a worry.....[&:]

If your DME relay is the old type, and that would be very old, it's worth changing for the new one anyway. They rarely seem to fail now, as almost all have been replaced.

 

[pse_SC]

I wish I had a 13-pin Kompa

Not like his, you don't[]

Oh, and the 993 relay mentioned might be the same one which is often advised to be replaced on a 993 (some of which had 944 DME relays on them[] so updated one is a more "˜reliable' replacement).

 

[leepox]

Right. I will have to buy that DME relay as back up in the glovebox.

Big Q now is... if I replace the old DME relay with the new one, that means I can disconnect the connection to this pump relay and not have any problems?

 

[pauljmcnulty]

Big Q now is... if I replace the old DME relay with the new one, that means I can disconnect the connection to this pump relay and not have any problems?

That's got me more confused now! [&:]

Is this a second DME relay? If it is, and assuming the main one is reasonably new and the car works, I'd be leaving this second one well alone.....

 

[leepox]

What I meant was that my Current DME relay and that "pump relay" behind the dash are fine. It's just that I am trying to figure out why my car is sitting rough during idle (vibrates a lot). When cold and I rev a bit (even to 1.5k), once I let off the gas the RPM drops all the way to zero and the engine dies. It doesn't do that when the engine is warm.

So I am currently sorting any problems that could be related with engine management. I.e. Relays, Harness, AFM, Auxilliary air valve, DME unit, distributor, ignition wiring, etc etc. In fact maybe it's just as simple as cleaning the wire contacts to the temp sensors in the engine bay :/ If that doesn't sort the problem then I am gonna start looking at mechanical bits. So almost basically what happens to this dudes car when cold but of course I haven't done it deliberately. http://www.youtube.com/watch?v=ZOFC42u3O7k

And my comment about buying a spare DME is just for the in-case first-aid. Just wondering if the new DME makes the pump relay completely obsolete and disconnecting it would be OK in that case.

 

[tref]

Just putting two and two together... You have an early dash car with air-con?? I am jealous... (OK, it looks like it is white rather than black, but hey...) Anyway... Keep in mind that the air-con also plays around with the air admission into the engine when it is switched on and off, that this could be a relay related to that perhaps, and it wouldn't show up on the main diagrams (I think), but also if the air-con extra omph to your engine valve could cause the problems you have if everything else is correct.

 

[Chris_in_the_UK]

Item is listed here:-

http://autopartmaster.com/en/?action=catalog_show&cat=porsche&t_id=15580&id_pic=742&cod=171937545

(between the items numbered 20) and it refers to a technical information document GR.2 NR.3/85 which seems to be about the DME wiring harness.

http://www.the944.com/dmerelay.htm

 

[pse_SC]

It's just that I am trying to figure out why my car is sitting rough during idle (vibrates a lot). When cold and I rev a bit (even to 1.5k), once I let off the gas the RPM drops all the way to zero and the engine dies. It doesn't do that when the engine is warm.

To be honest, from what you describe here, it's like all early 944 and 924 before they warm up! Once up to temp, though, they'll be fine. Give it a chance to warm up, it's not a spring chicken (i.e. modern eurobox). Check the warm up regulator.