Rod Underwood

Well, the twin screw that was starting rich occasionally and missing on start up, now won't start and run. Driving down the road, everything is fine and it just quit running and won't start.

Brought it home and it would start, but would only idle very roughly, try to give it fuel and it would die. Lots of clicking constantly from the pasenger side of the engine and fuel pressure low. Went out a few minutes ago and tried it again and it wouldn't start.

The fuel pump is relatively new, new when we installed the twinscrew, but anything is possible I guess. I haven't checked relays or anything at this point, just put it in the garage and went inside and said bad things.

Thoughts are welcome, but make them good thoughts.

Rod

Ducman82

how does the oil look? any fuel in it?

andy-gts

Brain malfunction?

Rod Underwood

No thank goodness, that's what makes me doubt that an injector is stayiing open - which would account for the richness. Or if it is staying open, it's only intermittent, at least up to now.

Rod

Rod Underwood

Yes, I thought I'd try swapping them out tomorrow after school. The LH is a John Speake rebuild, so I'm hoping it's not the problem. I guess we'll see.
It does have a programmed chip in it. I don't know how vulnerable those are.

Rod

IcemanG17

Hard to tell at this point.....lots of variables still...... I would start by jumping the fuel pump relay & go from there....

Vlocity

What kind of vacuum / boost numbers were you seeing ?

What was you fuel pressure at idle?

Are you using a mechanical FMU or did you have a chip made? I had a diaphram fail in the mechanical FMU once that caused a lot of problems.

Ken

Rod Underwood

I hate this!!!

Went out tonight and switched the starter and fuel pump relay and it started right up. I hate intermittent problems. How can you solve them and how can you trust the car when it's in this condition. I guess I'll start it and drive it around the area once or twice a day to verify that the relay was the problem. On the other hand, just switching them, suggests that maybe it was bad and maybe not, perhaps a bad connection at the relay?

ARGGGGG!

Rod

Popo928

Keep an eye on the relay and it's temperature. Might want to go ahead and swap it out for a known good one. After the swap if the new one gets hot, the pump may be faulty. Then try send 12v directly to the pump and see if it has any strange sounds. One of the guys at SITM had a similar issue.

Rod Underwood

I'll do that. I'd be surprised if the almost new fuel pump is bad, but you never know.

Nice to meet you at SITM.
Rod

AO

Yeah, the guy who had that problem is also from Indiana...

Turns out the Fuel pump was going out and drawing too much current. Killed the relay. New fuel pump solved it.

IcemanG17

since its intermittent I like grounds issue...maybe the act of pulling and switching the relays was enough to improve their conductivity just enough to work properly.....