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240 ECU problems

The O2 Sensor signal wire (maybe there's only one wire on yours) should have somewhere close to .5 V on it when you first start the car... after warmup for a couple of minutes (try to rev engine to 2500 rpms or so for 2 min. to make sure sensor gets warm) the sensor should fluctuate between .1V and .9V. The .1V signal indicates lean, the .9V signal indicates your car is running rich telling the computer to send less gas.

If it stays at .9V the O2 sensor could be bad... there's testing procedures on the board somewhere... do a search for oxygen sensor...

I found an ECU for my '86 in the junk yard for $30 (including the core charge) now I have it as a spare to eliminate the computer as a source of problem when troubleshooting.

test the O2 sensor before trying to rig something up, I think sensors for the early 80's vehicles are pretty reasonable.

jack
--
Bad Blue, '86 245, 244,000 mi.






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New 240 ECU problems [200][1980]
posted by  redseahornet  on Tue Dec 3 09:40 CST 2002 >


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