Show Posts
1
Engine + Driveline / Cranks But Won't Start—Fried O2 Sensor and Main Relay
« on: May 27, 2018, 11:50:35 PM »
My '91 died on the freeway a few weeks ago, and my mechanic just gave up. Here's everything I know:
It cranks but doesn't start. According to my mechanic, the O2 sensor and main relay were both fried. He also says that it fried the DME, but I don't think he's removed it or anything, and when I took it out it the circuit board looks totally clean.
Mechanic says it's not the fuel pump or crankshaft sensor, so I've ruled those out. He says it's a short in the engine wiring, as you can hear a brief click when you plug in a good main relay. I've removed the wiring harness, wrapped a nasty bare spot on the large alternator wire, and replaced it all, but no progress. I'm lost.
Thanks,
Alec
It cranks but doesn't start. According to my mechanic, the O2 sensor and main relay were both fried. He also says that it fried the DME, but I don't think he's removed it or anything, and when I took it out it the circuit board looks totally clean.
Mechanic says it's not the fuel pump or crankshaft sensor, so I've ruled those out. He says it's a short in the engine wiring, as you can hear a brief click when you plug in a good main relay. I've removed the wiring harness, wrapped a nasty bare spot on the large alternator wire, and replaced it all, but no progress. I'm lost.
Thanks,
Alec