Problems starting engine in rain.

[MikeCT]

When i went to start my car up last night it had some trouble starting but after it warmed up the engine was fine. The same thing happened today. It seems the rain is affecting how it starts. Could this be from a cracked distributor cap? I haven't actually gone and check it yet because it has been raining.

[SoCal Driver]

Sitting in the rain or from driving in the rain?

Driving: Your timing belt will pick up water through the crank pulleys and stuff it into the dist cap if the baffel-cover is missing behind the rotor.

In rare cases I've seen the terminals on the water pump get wet and loose condutivity.

[MikeCT]

no problem when driving or sitting but when i first start up the car after it has been raining it takes more cranking then usual.

[ronin]

SoCal, water getting through the bottom of the windshield/firewall area into the electronics?

[MikeCT]

That is a possibility because I park on an incline. The water may not be draining well.

[ronin]

yep, right around the area of the battery box could be a potential culprit

[SoCal Driver]

Originally posted by ronin
SoCal, water getting through the bottom of the windshield/firewall area into the electronics?

84 has it mounted under the steering column just above the drivers knees.

Could be getting the terminals on the battery soggy. A bad terminal will cause a bit of resistance when wet. If driving in the rain then the starter terminals could be wet also.

Can't think of anything else that will get wet if the car is left standing other than the battery.

[ronin]

y'know, I've been meaning to see what I could find under the column. what type of FI system does the 84 have? does it have an ECU?

[SoCal Driver]

The 83, 84 and early 85's have 95% of the same DME brain as the later NA 944's. As you have read when some what to use a newer DME in a later car they have to change out the AFS and the idle possitioner.

The air flow sensor uses a lower control voltage, 4 rather that 8 VDC, and had a slightly different resistence curve. The idle possitioner is controlled by the DME rather than being a timed valve (heated bimetalic spring).

They use the same plug with the newer DME having a few extra wires for the idle possitioner.

Think the 951 DME uses the same plug.

[ronin]

yes, I do remember the issue of having to change the AFS and i/p for the later DME. interesting to note (I just found out) that the self-diagnostic process wasn't available until 88. (that's what I refer to as an ECU) curious that they would put the DME on the steering column. same place as the central locking control unit

[SoCal Driver]

"curious that they would put the DME on the steering column. same place as the central locking control unit."

If you already have a mounting bracket there why not use it.

Some of the changes make sense; some don't.

[ronin]

definitely makes it easier to get at as well. I had my power locks stop working one day and I said to myself "I'll fix it when I get home." I jumped into the car and noticed something rubbing against my leg. I looked underneath and saw the central locking control just haning there(!) I simply plugged it back in and voila! easiest fix ever

[ronin]

that would have been nice! but cinsidering that this incident happened right at the end of a date with my girlfriend, it would have been awkward to say the least! and what kind of chick fits in the footwell these days anyway??

[ronin]

oh gawd! lol

[Mark_944S2]

Knackered ignition leads. They have cracked inside and in damp conditions the spark jumps to surround. Once warmed up the cable expands and closes the cracks. Seen it several times causing bad or no damp starting. Get yourself a good, new set of ignition leads.

Mark