QuestionHi,
Thanks very much for offering help!
My 1990 toyota corolla (4 cyl., automatic, 4A-FE engine, made in the US) died completely while driving at 50 mph a few days ago. It went from running fine to dead with no sputtering or warning whatsoever, as if the key had been turned off. The headlights, instrument panel, radio etc. work, the engine turns over, the fuel pump pumps gas (I have not done a fuel pressure test), no-load battery voltage is 12.7 (after substantial cranking). I removed a plug and grounded the body with a jumper cable--no spark. I checked the fuses in the driver's panel and the fuses in the engine compartment, and all are fine. I felt the relays while turning the ignition on and off, and can feel all of them click closed. Then I opened my Chilton's manual. I found battery voltage at the positive terminal of the coil with the key in 'start'. The primary and secondary coil circuits tested within spec., but the signal generator tested at 165 ohms instead of the specified 205-255 ohms. The manual recommended replacing the distributor housing. I bought a remanufactured distributor and installed it with the body and rotor in the same position as the original. Still no spark. I tested the new distributor and found that the signal generator now tested in spec., but the coil primary windings were not in spec. (they tested .3 ohms instead of 1.25 - 1.56) and the secondary windings were out too (8 ohms instead of 10.4 - 14)
So to my questions:
1.)Where do you think the problem is?
2.) would this cause my no spark problem? If so I plan to use the old coil in the new distributor.
3.) I would like to test the ECU, but have no info on how to. At the end of the list of checks, the Chilton's manual recommends testing the IGT signal from the ECU, but doesn't tell how or where to test. Not helpful! Their wiring diagram is incomplete and badly printed. I have a MAC automotive multimeter and a computer safe circuit tester and have removed the kick panels around the ECU. Can you tell me where to check for the IGT signal and how to test if the ECU is fried?
Thanks very much for your help, please feel free to add any comments etc.
Thanks, Sam
AnswerThe IGT signal is a timing signal input to the ECU but I don't think that's where the problem is, if I remember correctly the coil is located inside the distributor, if it is replace it regardless of the readings you are getting, did the rman distributor housing come with the coil in it?
If not install a new coil and see if it fixes the no start problem.
