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Thu Mar 06, 2008 7:06 pm

She cranks over fine. She was running until today. I changed the sparkplugs and oil recently. How can I tell if the fuel pumps or distributor isn't working? It's my girlfriends car so I've only done little things on it. I'm not to familiar with the inline 4's. My guess is it's the pumps or the the spark, maybe the coil?

Thu Mar 06, 2008 9:53 pm

The relay for the fuel pumps kicks on for a brief moment when the key is turned on, then after that only when there is a coil signal being generated. I'd check for spark (take off a spark plug wire connector, screw a long deck screw into it, then hold it so the screw is a 1/4-1/2 inch from bare metal, like the cylinder head, and have someone crank it over. You should be getting a decent spark. If you are, then check that the fuel pump relay is kicking on, you can usually hear it do the initial click-click when the key is turned on, then again when there's spark present. If you aren't getting any spark, pull the distributor cap and look and see if it spins when someone cranks the engine over. If not - you probably lost a timing belt.

If you have spark and the fuel pump relay is going, then the next biggie is the in-tank fuel pump. These have about a 10 year reliable lifespan. Many main fuel pumps have been needlessly changed out over the years becuase it was the "transfer pump" (as the factory manual calls the in-tank lift pump) has gone bad. It's kind of a pain to get out in a Fox, on a sedan it really helps to remove the rear seatback cushion to be able to get to the pump so you can get it out - it's under a metal cover and if you have to remove it, it's a twist-lock that can be somewhat difficult to turn. It has an inlet and an outlet line on top of it. Now, If you bypass the fuel pump relay (with jumper wire) so the pumps run, the transfer pump should put out 13 ounces in 10 seconds. Usually they just stop working period.

Those are the things I'd check first.

If you need to do any real work on this, you really should buy the factory Fox service manual from Bentley Publishers, it's a good book and fairly reasonably priced, if you compare it to manuals for some of the other watercooled VWs.

http://www2.cip1.com/ProductDetails.asp?ProductCode=ACC%2DC30%2D9662

Thu Mar 06, 2008 10:45 pm

Thanks, I'll test the spark and listen for the fuel pump relay.

Fri Mar 07, 2008 10:38 am

Well, when I turn the key the fuel pump is not turning on. That is I am not hearing it turn on. Now I am curious if it is the pump itself or the rely? I am not sure where to look as I don't have a manual yet.

Fri Mar 28, 2008 9:16 pm

You won't hear the fuel pump turn on with a stock vw fuel relay. It doesn't power the pump until you actually turn the key and the ignition switch engages. With aftermarket fuel pump relays, you will hear the pump turn on as soon as the key is turned.