Fw: Odd engine problem on a rainy day . . chug, chug, chug, chug
syljay at optonline.net
Tue Jan 6 16:44:00 EST 2004
Update 2 - 90 100q
Yesterday the outside temperature was in the low 30's, rainy day.
Went to start the car. Cranks fine, I can hear one or two cylinders try to
catch. No start.
Tried it 4 or 5 times. Tries to catch once in a while, but wont start.
I spray the ignition wires and ignition related parts with wd-40. Close the
hood and leave the car alone.
Colder, and dry . . temp must be in the high 20's . .snow flurry here and
Put the battery charger on for couple of hours . . just in case I took too
many amps out yesterday.
Pull a yellow plug in the black rubber intake air boot, attach a rubber
hose, and set up for injecting starter fluid.
I figure I have a temp sensor problem and cold start valve is not turning
Standing by . . .wife cranks the engine . . .goes over once, twice .
Historical Summary so far:
1 time - cold damp day, cold start, short drive, shut off engine, restart in
15 minutes, chug chug chug for 6-10 seconds
1 time - dry warmer day, cold start, short drive, shut off engine, restart
in 15 minutes, chug, chug for few seconds.
1 time - wet cold day, cold start, wont start . .. sounds like it tries to
start on one or two cylinders.
next day - cold dry day, cold start, starts right up.
Who has some good clues for me? I'm leaning in the direction of the ignition
But, it could also be some temperature sensor that is messing up the fuel
There are two water sensors at the top front of the engine. The bottom
sensor is the MTF, and the top sensor I think controls how long the cold
start valve stays on.
Are there any other temperature sensors used by the computer?
Would an intermittant idle switch cause this problem?
I'm ready to swap out parts.
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> Went to same store today, afternoon. Sunny dry day, temp was about 45-50.
> One mile drive.
> Started car after it sat for about 10 - 15 minutes.
> Started ok, rough idle . .gas peddle had no effect. Cleared up in about
> 10 seconds. Some hesitation when coming off idle. After a few minutes it
> cleared up . .no more problems.
> I think the Ignition is eliminated as the cause of the problem.
> I'm thinking one of the temperature sensors is telling the CPU that the
> engine is fully warmed up when its not, and I'm getting a lean mixture.
> How many temperature sensors are there? Is the MFT sensor the main one
> I should be looking at?
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> Sent: Thursday, December 25, 2003 12:32 PM
> Subject: Odd engine problem on a rainy day . . chug, chug, chug, chug
> > It was cold, foggy, and raining yesterday. Temperature was about 50 F.
> > Oregon style weather.
> > Drove the 90 100Q to the store . .about 2 miles away. Parked and shut
> > engine.
> > Came out of store in about 20 minutes, started engine.
> > Started up ok, but sounded like it was running on one cylinder. Pressing
> > down on gas pedal did not change the RPM . . .chug, chug, chug, chug . .
> > sounded like a one cylinder diesel engine on the African Queen.
> > I let it run this way for about 30 seconds or so . .figuring it was wet
> > something in ignition was misfiring. Maybe it would dry out a bit.
> > After about 30 seconds or so, the problem cleared up, no more chugging,
> > pedal worked.
> > I drove home gingerly. There might have been a slight hesitation or
> > going from idle to part throttle . . I'm not sure. I was very easy on
> > throttle because I didnt want to be towed home.
> > Today, I sprayed the ignition wiring, coil, booster with WD 40. Weather
> > sunny, dry, 35 F.
> > Car started up with no problem. No missing, no hesitation.
> > The ignition wires and cap and rotor are about 1 year old. Maybe 4k
> > them. Same for the plugs.
> > ISV valve was cleaned about 500 miles ago . . nothing was wrong with it
> > .just preventive maintenance.
> > Any ideas?
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