[jdh]

The secondary air pump relay in my 96 passat tdi apparently shorted out yesterday and burnt up. Other than the smell and small flames i found when I popped the hood, the car seems to run fine. Does anyone know exactly what it does and if there is any reason not to drive the car until replaced?

 

[Fluid]

Exactly where is the relay? What is the number printed on it? Or is it a fuse? The 96 TDI has a solenoid and 5th fuel injector that can be disabled without problem but a secondary air pump relay sounds like a gasser emissions device. The 5th fuel injector is a TDI emissions device that might be equivalent.

 

[chittychittybangbang]

Do you have a picture? That would help a lot in identification. If you're not sure how to post a pic see this post:

http://www.myturbodiesel.com/forum/showthread.php?t=1044

 

[jdh]

It is just under the rear of the hood, just behind the coolant resevoir and to the left(passenger). Its about 2.5 inches wide. It has one bundle of wires in the middle and single wires on either side of that which are held in with hex bolts. There is no number as it burnt/melted.

 

[5point]

Did it have a clear plastic lid on it? It sounds like the coolant glow plug relay.

 

[chittychittybangbang]

Is this it? Not the green arrow (daylight running light connector) but the box to the left of it with the red wire and clear plastic box.

That is the coolant glow plug relay. It's a very common issue. The best guess why it happens is corrosion on the wires and wire damage causes overheating of the fuse. It overheats and the fuse normally melts. It appears that in your case it caused a small flame. Good thing you caught it. There are other common issues in the new owner checklist, this is one of them.

 

[jdh]

That's it. Thanks. I installed a frostheater three or four months ago. I wonder if that has anything to do with it. Can't really hurt the car driving though huh. Know where you can get the part.

 

[chittychittybangbang]

It has nothing to do with the frostheater I'm sure of that. The problem is probably related to corrosion on the wires.

It heats up the coolant for faster warmup and reduced emissions.

If the fuse was blown I'd just replace the fuse but if the entire thing is gone and since you already have a frostheater, you may want to bypass it. I would not. Either way you should carefully examine all wiring in that area if there was a small fire. Make sure there are no shorts or exposed wiring.

If you choose to replace it the part number is 191911261B

http://www.tdiparts.com/catalog/product_info.php?cPath=29_90_94&products_id=1191

As you can see it's a common enough problem that they carry it in stock.

 

[freerider]

Yep, mine was melted too and you could see some melting on the plastic.