zekgb

I'm experiencing a recurring no-start issue that has me flummoxed. Conditions are when the car has gotten wet after a short drive of 10 minutes or less (usually after a rain, but occurred once after washing the car at a self service place) I get a no-start condition that resolves itself 10-15 minutes after initially attempting to start the car and attempting to restart every couple of minutes. This condition does not occur when the car has sat overnight in the rain nor after an extended drive in the rain. It has also never happened when the car was completely dry. Car cranks well during these episodes and I can hear the fuel pump (recently replaced when the problem first occured) running. Once started the engine runs perfectly with a rock solid idle.

I've checked for moisture at the ECB (no sign of it) and swapped all possible relays and fuses. All of the ignition components are new with the exception of the amps and show no sign of moisture. Temp II / connector replaced as part of engine out service last summer as were the CPS and its connector. Seems like with this behavior something is getting wet and without enough engine heat built up is staying wet. Does this sound right and if so any ideas on likely places to test / troubleshoot?

gazfish

Have you got a cover over the 14 pin connector by the jump post?

zekgb

Oh yes, forgot to mention that. Cover is in place and I've inspected the connector during these episodes and found it to be moisture free.

Mrmerlin

it is probably time to replace the ground strap

zekgb

Assume you mean at the battery, but I guess doing the cable at the block wouldn't hurt as well.

Mrmerlin

OK do both but the battery ground strap is the one that often fails

928S MN

I had an intermittent problem in the rain only. Turned out to be the Ignition Modules on my 85. Changed them out and no problems since. And I also thought it was the battery ground strap. When I changed that first, no difference with the intermittent rain problem.

zekgb

OK that's interesting. Was your problem no-start only or did you have drivability problems as well?

928S MN

My problem wasn't a no start issue but a drivability one only.

Thought I'd throw it in the mix here because it was so frustrating to track down.

Even though you initially stated you can hear the fuel pump running, during the no start events, are you a 100% sure it's not a fuel related issue? By this I mean have you had the LH module rebuilt?

zekgb

No I'm not confident of much at this point other than the fuel pump appears to be delivering fuel as it's never happened at home where I could do much in the way of troubleshooting and always resolves itself within a 15 minute window. LH hasn't been rebuilt but I'd rather not go that route till I've exhausted most of the other throw money at new parts options.

davek9

So it cranks but wont fire up?
If so, grab an old inductive timing light and see if it shes getting spark, at least you can rule out one of two, (spark and fuel) systems.

Dave K

Landseer

Can have coil end corrosion degrading spark though.

Kiwi928S4

I had the same problem - after washing and wet weather - found both coil leads had cracked insulation - put new ones on and problem solved!