1988 Isuzu Cold Start Problem

I've got a 1988 Isuzu I-Mark that has a cold weather starting problem.

When it's cold outside, it will start up with a really fast idle (2000 RPM) for about 3 - 5 seconds, slow down to about 1500 rpm's for a while (10 seconds perhaps) then start bouncing down to around 500-600 RPMS, almost stalling, then back up to around 1200-1500 RPM's, and repeat this process maybe 10 - 20 times before the engine seems to find a good place to idle at. When the car is warmed up, the idle is rock solid at around 900 RPM's.

Last week, on a really cold morning, it would not start at all. The starter would turn, the engine would start for about 1 second then sputter out and die right away. After about 2 -3 hours later, it started like normal (normal with the jumpy RPM's).

I'm thinking engine coolant temp sensor... can anyone please help me?

Thanks!

Reply to
i-mark
Loading thread data ...

Possible.. but could also be something like a dirty throttle body or idle air control valve..

Reply to
Robert Hancock

You shouldn't be able to start if coolant temp is dead. A diagnostic would be to unplug this sensor when you can't start in a cold morning.

Check for trapped air or the wax thermo sensors. This sensor, in conjuction with the idle control vavle, could bring rpm to 2000rpm and back down. On some vehicle the there are plenty individual wax idle sensors. Rick

Reply to
Ricky Spartacus

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.