Gregg K

Pfunde, I would check it, but it's 3:30 in the morning, and my voltmeter is just about to go into the moving truck. And welcome aboard to the forum. Wow, 322 hp in a 78! Very cool.
Yes, I've run out of time. I'll just have the owner tow the car, and they'll have to deal with it.
Thanks for the advice, though.

Gregg K

I got the new fuel relay, and plugged it in. I had the horn relay swapped in it's place. And with that there, the fuel pump ran. But when I plugged the new relay in, the fuel pump was silent. What's with that? Now why would the horn relay make it work, and a new fuel pump relay not work?

Any ideas on this newest mystery? I feel like starting a new thread on this subject alone.

SharkSkin

The correct relay for the pump will only activate if it's getting a spark signal, but IIRC it's supposed to come on for a brief period when you first turn the key.

HTH

Gregg K

Aha!
Thanks muchly for your input on this. I have to admit, I kind of thought that was the case. Makes sense. I really appreciate your help, as I'm doing this in absencia. The car is in California, and I'm in Oregon, and I don't have the manuals.
Next it's off to get a new sparky module.

SharkSkin

Gregg, I don't think that necessarily means you need a spark module... I was just mentioning the expected behavior. With the horn relay, the fuel pump ought to run any time the key is on. With the correct fuel pump relay that's not necessarily the case. So it could still be behaving correctly from what you describe. The test would be to see if you have a tach signal on one relay pin while cranking. Also, see if you have spark... you never mentioned what you found there.

Gregg K

They just put the ignition module in the car, and it still doesn't run. I see the post from Dave, and see the tests that need to be performed. Unfortunately, I'm trying to help the girl who bought the car from me. But I now live in Oregon, and the car is in California. I'm a novice with the 928 diagnosis, and the girls are pretty much lost, but with manuals in hand. I'm not sure what the best way for them to check spark is. And I don't know which relay Dave is talking about when he says to check for a tach signal. Any other ideas?

Bill Ball

Where in CA is the car?

heinrich

Dude you say the words "girl"; "928" and "needs help" in one breath and you'll have 100 takers right then and there .... Mr Ball, how about some of that famous troubleshooting wizardry?

Bill Ball

Heh, heh...I've got this one covered.

Gregg K

Shame, shame, shame.

Actually, I feel the same way. The real shame is that I just got to meet the one, before I had to move. It's great to see girls working on mechanical things. I think they're better at being patient while diagnosing problems than I am.

The car is way up in Humboldt county. Sorry folks. I doubt anyone in the forum lives anywhere near it.

I think it's still missing spark, but I'll have them check it first. More later, you soundrels!

BC

The spark box didn't help? Hmmm. Thats a known good one, tested on two different cars.

Grounds?

sublimate

Damn! Not just "girl", but "girls"! Like they say in Cali, two girls for every boy.

Gregg K

Ijust got an update. Angela (why oh why did I have to move!) said that the ignition relay is bad. If so, I made a stupid mistake, and missed it. I just went for the fuel pump relay, since it wasn't running when the key was on. But evidently these newfangled cars are smart enough to turn off the pump if the ignition isn't functional. So.....she has 928 Int'l's phone number to order a new relay, and all should be up and running.
Wow, this girl has been working on cars since she was a kid. I think this car is in good hands.

heinrich

thought so, I would have been disappointed to hear otherwise

Bill Ball

I want to meet her, er, I mean , see her car.