yet another starting issue question

[c2kid]

aloha all, i'm not really fluent in 944's, and I need some help with this one. I have an 83 944 that refuses to start at all temperatures without a squirt of starting fluid (even diesel starting fluid works). it runs super strong and has no issues once started, no stumbles or misses thru the whole rpm range. the problem was intermittent originally. fuel pressure tests spec and it has good spark and cranks great. fuel pump, filter, ignition parts, and temp sender are all new. I've read all the threads and have tested everything including swapping in a known good ecm. is there an enrichment circuit on these?? the only thing I haven't tested is the afm and I don't think it's it as it runs so smooth at all engine speeds. no stalling or any bad habits once running. i'm gonna test the afm this morning. ideas deeply appreciated. cheers, geoff

[mikepellegrini]

How is the leakdown rate? I think the spec is something like 20 psi after 30 minutes or something.

The fuel pump has a check valve that's sposed to hold the pressure after you turn the engine off. If that failed, it could possibly create the situation you have.

If you crank it for a really long time, will it eventually start? Or absolutely only with the ether?

[fiat22turbo]

How are the fuel injectors? What's their spray pattern look like?

[mytrplseven]

Originally Posted by mikepellegrini

How is the leakdown rate? I think the spec is something like 20 psi after 30 minutes or something.

The fuel pump has a check valve that's sposed to hold the pressure after you turn the engine off. If that failed, it could possibly create the situation you have.

If you crank it for a really long time, will it eventually start? Or absolutely only with the ether?

I'm with Mike on this. It sounds like the check valve in the fuel pump may be allowing the fuel system to drain all the fuel out of the supply line. There's a procedure for checking the leakdown rate on Clark's Garage to verify. If there's an Autozone in the area, they have gauges and stuff to loan.
I just moved back to the Mainland from Kona Paradise (south of Kona 45 minutes) last year.

[Tim L]

Have you tried starting it with a battery charger connected or push starting. I had a problem that I believe was the starter using too much current, lowering the voltage so the injectors didn't fire. I rebuilt the starter and it now starts.

[c2kid]

good ideas, i'll check the leakdown although it's a new fuel pump. might just be an injector. I had the starter rebuilt a year ago so it should be fine, but i'll try a push start. cheers, geoff