1989 electrical problems need good mechanic

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warrensmith
Hey. They are NOT Training wheels.
Hey.  They are NOT Training wheels.
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1989 electrical problems need good mechanic

Post by warrensmith » Sat Dec 13, 2014 7:15 pm

My 1989 has a couple of problems that my mechanic can not seem to solve, first on start up from cold runs very rich , flooding with plenty of smoke and miss firing for about 5-10 mins then clears and run fine and 2nd problem now and again wants to die/cut out completely on idle and if you catch it quick and keep the revs above 2000-3000rpm for a little while it will come right, Possible ecu, throttle position sensor? I need somebody who knows these cars and how to find these problems Can somebody help this has been driving me insane (plugs etc all be checked changed etc) :x

4A-GE
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Post by 4A-GE » Sat Dec 13, 2014 11:43 pm

Um oxygen sensor?

WideOpenThrottle
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Post by WideOpenThrottle » Sun Dec 14, 2014 8:47 pm

I'd be checking Airflow meter,intake tract for leaks, vacuum system for leaks, clean the throttle valve and IAC valve, timing, fuel pressure and fuel injectors, spark and compression. Sometimes the keyway in the cranknose shear's which puts the timing out. Maybe try another ECU / AFM. Just a matter of elimination.
I think I still have spare injectors, ECU and AFM if needed. Happy for you to try any to help eliminate if required.
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marcellarius
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Post by marcellarius » Mon Dec 15, 2014 10:48 am

It's not the oxygen sensor. The O2 sensor is used for closed-loop fuel control once the car is warmed up.

The main mixture control during warm-up is the engine coolant temp sensor. This would be where I'd look first. It's located on the water outlet on the back of the engine. There are two sensors: one drives the temp gauge, the other gives a signal to the ECU.

The idle problem could be related to mixture, could also be a large vacuum leak or air getting in without being measured by the airflow meter.

warrensmith
Hey. They are NOT Training wheels.
Hey.  They are NOT Training wheels.
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Location: auckland

Post by warrensmith » Mon Dec 15, 2014 8:32 pm

thanks very much for all your help , do you know of any good mechanics out west that know these cars well

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