Hi All- My '85 Mondial has been giving me a hard time when starting. I'm 99% sure it is an ignition related problem. Here are the details: 1. The car cranks fine. I would not suspect a starter or weak battery problem. 2. As once suggested, I hooked a timing light to the rear bank coil wire. I cranked it a couple times breifly and the light did not blink. 3. The third time I tried, the light flashed like crazy and the engine fired up for about a half second and died. 4. Every time I tried to restart after, it did not fire, nor did the timing light blink again. 5. I also tried the front bank coil wire - no timing light blink. It seems that this is affecting the entire ignition system. 6. Here's a weird one: I checked what is supposed to be the coils battery voltage at the diagnostic plug, and I am only reading 8.9VDC. The battery voltage is measured at 12.4VDC. There are, according to the wiring diagram, no connectors between the key switch and the coils. I'm in the process now of determining if the diagnostic plug reading is the same as the true coil battery voltage (there is a connector between the coils and the diagnostic plug). 7. When the car finally does start, it runs great. The ignition never "mysteriously" cuts out when it is running. So... What caused my ignition to come to life only breifly on the third try and as Edgar Allen Poe wrote: "Nevermore"? I'm almost thinking the ignition switch itself, but I'm wondering if anyone has some input or tricks to try to help me streamline my troubleshooting (and agony). "Anyone?... Anyone?...
Sounds like: A. loose connector B. Corroded terminals/wiring C. Fuse Panel circuit board burning/melting D. Loose ground Take your pick and start checking.
Well, I slept on it and took a fresh look at it in this morning... ...AND I HAVE GOOD NEWS!!! SHE STARTS!!! One thing that puzzled me was the 8 volts at the coils. I back-tracked the wiring and went to the key switch connector at the base of the steering column. I had 12 volts heading up the column to the key switch but only 8 volts coming back towards the coils. I hooked up my meter to the key terminal and repeatedly cycled the key switch back and forth. I found that it read 8 volts almost every time. About every 20th time it would actually pass the full 12 volts - but now would not complete the starter circuit to the starter motor. Sounds like the key switch is the culprit, huh? I played "grand theft auto" and hot wired the ignition with a test jumper and a remote starter button connected to the harness connector. She started right up! First time - every time! So, unless I plan to drive my car with an alligator test jumper and a mechanic's starter button hanging out from under ther dash, I will be on the hunt for a new key switch. Maybe I'll try contact cleaner first and see if that works. But first, a trip to the archives to see if anyone has instructions on how to get that darned switch out out of the column! And I read that one about the AC last night - guess what was the first thing I checked this morning! (It was off). Thanks to all. -Jon B.
The coils have ballast resistors, either internal or external (I don't remember which) that step down the voltage to 9v to help perserve the points. That's why you are seeing the reduced voltage at the coil.
There aren't any points fitted to that car. It has digiplex with flywheel mounted sensors for each bank.
Well, here's what I found - Since the 8 volts at the diagnostic connector was puzzling me I decided to start there. Like I said, I ended up at the harness connector leading up the column to the key switch. I had 12 volts going up the column but only 8 volts coming back down, heading to the coils. Apparently, 8 volts is not enough for the Digiplexes and coils. So... I searched the archives, found out how to get the key switch out, hosed it down with electrical contact cleaner (out of the car, of course), reconnected and TA DAH! DONE! It's the simple things in life that thrill me. Thinking about it now, it almost seems dumb. "Why doesn't my car start? Must be the key (switch)". Dumb, but true. My thanks to all (and the archives) - Jon
