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engine sputters in the rain

2865 Views 6 Replies 5 Participants Last post by  Darryl Metcalfe
Here's the scoop on 2 problems...

The first:

My '86 9k turbo tends to sputter on rainy / damp days or after running through average sized puddles. I lose power unless the throttle is floored. Once it warms up after ~5 - 10 minutes of driving, all is fine. Doesn't sound like one cylinder is misfiring, rather, it just drowns itself out (perhaps the distributor cap rotor should be changed?). The mileage readout goes way up when this happens. I changed the wires, plugs, and distributor cap. Used dielectric grease on all contacts. Cleaned the IAC (for other reasons). I'm thinking maybe there is a problem with the air flow sensor? Too much fuel going to the engine? Any ideas?

The second:

Saabrina seems to have problems with cold starts. After sitting in the parking lot for a full day or overnight, it takes 2 - 3 attempts to get her purring. It cranks, turns over, dies immediately. I typically get her going by fiddling with the gas peddle, pumping it to maintain the rpms around 1500. Once they rpms stabilize, it runs and idles fine (unless the first problem occurs!). Note that warm starts are no problem at all.

I'd like to get these both sorted out by the end of the summer, to avoid problems during our bitter Canadian winters. Any hints would be greatly appeciated.

Cheers,
Darryl
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I don't know the answer but it sounds electrical. I have found the solution to many damp related starting problems by trying to start the car from cold on a damp evening in the dark. Any short circuit sparks are clearly visible and traceable.
My old ,87 turbo could be a little rough in damp weather with a mis-fire, cough and splutter - at this point I used to change plugs, rotor and dizzy cap which usually cured. Once warmed up any moisture present has evapourated so fine for rest of day. On one occasion after heavy rain, wouldn't start at all so called rescue services who got me going but suggested new coil which I replaced - solved problem but still not convinced the old coil was on the way out.

Mike
Sounds like a distributor cap, wires, or ignition in general. The caps can develop very small hairline cracks, or the contacts for the rotor, and the rotor tip could be pitted, etc. Sounds like it's time to change everything: plugs, wires, cap, rotor, condenser, etc. DI's may be expensive and less than immortal, but they sure do take the guesswork away from ignition problems
Oh, Saabrina: don't know what year or model she is, but sounds like a temperature sensor/NTC resistor. It's between cylinders 2 & 3 on the intake manifold and tells the ECM, via resistance, whether to add fuel (cold) or not (warm). Don't remember the resistances, off-hand, but they're not real expensive.
Traditionally moisture is the enemy of any car with a distributor if it is cracked or damaged.
Moisture impeeds the contact whether rainy or sitting overnight when there is moisture in the air(is Sabrina garaged at night?).

Change the distributor cap first. If the problems are not solved, then change , step by step, change the fuel filter and plugs. If that doesn't cure the issue, then go to the wiring and electrical. Often times, especially with a Saab, it is not a plethory of causes, but one cause.
I have changed the wires, plugs and distributor cap, but not the rotor or ignition coil. Does the rotor simply slip off or do you have to line it up properly? I'll get a new coil next week and try that too.

Moreso, I am interested in this temperature sensor someone mentioned. Is it only for coldstarts? Or what? I'd like more info. What about the air massflow sensor? Could it be faulty? ie. is it telling the ECU to inject more fuel without enough air?

Seems that the engine only has troubles when there are puddle splashes on the right hand side, not the left. Could be a coincidence though.
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