Hello Everyone,

Vehicle: 240GL Estate/Wagon 1988 Build with B230F 4spd Auto.

I have been having a problem for last 1-2 years with Engine Starting when engine / temps are Hot. ie. Temp. gauge around half way mark or above. Car turns over and starts but idle wavers and engine cuts out / all warning lights illuminate. If I touch the throttle and 'feed more gas' the engine will run and settle into normal operation (idle around 900rpm) after a few minutes...then it's all stable. Vehicle will perform as expected once stable. But if I shut it down again and restart when hot - the same problem just reoccurs.

There is no problem starting when engine's cold, first start for day, or in the lower range of operating temperatures. Winter there is no problems.

So far specific trouble shooting has consisted of:
- Cleaned Throttle Body.
- Replaced / new in-tank fuel pump.
- Replaced Thermostat just in case cooling issue. (this weekend)

The car has done around 220,000km. Fully serviced and maintained vehicle. Excellent condition and treasured.

As this problem only occurs when vehicle is hot, or been running at temp I and at a loss to find it's origin. It's Summer time and live in a Sub-Tropical location.

I would be most appreciative if someone has some ideas as to the cause of these hot starting issues??

Thank you. cheers Paul / Brisbane Australia.

 

the engine /should/ idle smoothly at about 600 rpm. 900 rpm is used for cold idle.

make sure the air flap in the bottom of the air filter box isn't stuck open, it should be closed, I usually wire it shut to prevent hot air from the exhaust heat riser from getting at the MAF and cooking it.

I'd probably verify that the engine coolant temp sensor is in range. take off the kick panel to the right of the right footwell, and the ECU should be behind it, just forward of the lower door hinge. get the engine fully warmed up, hot even, then shut off the car, unplug the ECU and measure the resistance between pins 2 and 5 on the cable harness side. with a hot engine, this should be like 200-300 ohms. wait til the engine cools off, with a 'room temperature' engine, its like 2000 ohms or something. with a freezing cold engine, its like 10000 ohms.