I just don't get it

[stomachmonkey]

New wires, BERU.

New cap and rotor.

Car stays covered, does NOT get wet.

Whenever it gets humid it won't start.

Turns over strong and eventually may catch, sputter and stumble then dies.

Had it in the shop, thought it was fixed. Ran great for a few days. Did not drive it over the weekend and get in it on Tuesday, same old story, won't start.

Weather has been "damp" till today. Kinda dry cool evening tonight, go out to car and it fires right up.

Only constants seem to be rainy days or days over 80 degrees with high humidity.

[Argo]

Maybe something in the computer / electronics? Was the shop air conditioned (making for drier air that may have dried the ecu out)? Just a guess, but I had an 84 vette years ago that also got weird in rain / damp and it turned out to be computer problems.

Argo
88 Targa

[kqw]

When was the last time the DME relay was replaced. It may be just a coincidence about the humidity and the weather.

DME's can be intermittent: If you have a spare, swap it out and see what happens.

[ChrisBennet]

Try this. With the car running well, spray the front (flywheel end) of the motor on the driver's side near the transmission. The speed and reference sensor insulation in this area tends to crack and may be the culprit.
-Chris

[felix_browne]

wait untill it gets dark but light enough to see. fire up the motor and spray a mist of water into the engine bay. you will almost surely see your ignition charge arching to the body or the engine from a crack in the insulation somewhere. likely a crack in the ignition coil insulation and not hard to fix.

[stomachmonkey]

Definately not relay. Checked that myself and the shop checked with a different one.

I'll try the mist thing.

Humidity is definately NOT a coincidence.

It's gotten to where I can tell as soon as I walk out of the house whether or not the car will start.

Thanks
Scott

[eddiehotrod]

What Chris Bennet said. I suffered for two years with my '84 not starting if I left it out in high temps or humid conditions. I removed the alarm and immobiliser, changed the DME relay twice and spent a good number of evenings fannying around in the fusebox with no joy. Then I changed the speed and ref sensors and no problems since. Update your head temp sensor while you're under there if you haven't already.

[RoninLB]

I know know nothing about the '84..

but shouldn't you be able to replicate the prob with a water misting, when it's running ok, on the sensors and ignition if that's the prob? I even read here about the pc board under the drivers seat becoming cracked although never read about dampness affecting it even when it was beat as in on/off.

[eddiehotrod]

Oh yeah, that reminds me. I also took the DME to bits a couple of times to check for bad solder joints, but the sensors were the fix for me. Ronin, I think the problem lies on the actual sensor/wire connection at the end which is right under the car on top of the flywheel, so testing with the car running could be tough. Stomachmonkey, one sensor is required to work just for starting (ref) and the other for constant running (DME signals) which may explain why it starts briefly then fails. Here's a great thread which helped me out (Thanks BGCarrera), hope this works: 3.2 Ref/Speed sensors

[Tyson Schmidt]

I agree with others about the DME. You should remove the brain from under the seat, and remove the cover. Check for moisture damage.

You may need to send it out for a rebuild.

[Lorenfb]

"Whenever it gets humid it won't start."

A common poor running or no start situation occurs on '84-'89 3.2s when
moisture or a distributor cap crack exists between the distributor cap and its'
black metal (plastic covered) shield. With that shield grounded to the distributor
housing, a high voltage breakdown can easily occur when the cap is marginal.