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Discussion Starter #1 (Edited)
This is for a 93 SC300, but you guys are much more apt to respond with actual help and ideas than any other forum.

My 93 SC300 has always been very reliable, save for basic maintenance. A couple weeks ago, it died. The day before, I drove it to work and back, and out and back on 2 errand trips and ran perfect. Started fine, no rough running, no problems at all. Went to start it the next day, and zero, nada, zilch. The next day I pulled the coil wire from the dizzy and held it against a shock tower bolt and absolutely no spark was coming out. I didn't bother to check for fuel delivery as I have no clue where I could pull a fuel line and put it in a bottle to see if it's squirting fuel.

Fast forward to today, I used the diagnostic procedure the best I could in the 95 Supra manual. I broke out my trusty multi meter and here's what I got:

Voltage/resistance at coil (had the spark plug wire and 2 wire harness unplugged), cold readings since the motor hasn't run in a couple weeks:

1. Voltage at + and a bolt close by for ground started at 66mv then quickly and steadily dove down to -100mv, at that point I just stopped. Even checked it on the other terminal in case I had accidentally put it on the -, and the other one read -235mv
2. Resistance at the + (wire closest to clip) and - terminal, it read .6 ohms
3. Resistance at + and the spark plug terminal read 8.43k ohms.

Resistance checked at the 4 pin connector on the distributor:

1. G1 and G- read 155 ohms
2. G2 and G- read 155.2 ohms
3. NE and G- read 193.9 ohms

I didn't check the air gap of the distributor or see how to check for voltage to the ECU or whatever, I just did the basic quick ones since they were the easiest to do for now and I'm extremely worn out from work. I also didn't see any way to test for voltage or resistance at the igniter.

What I can say, other than the fact that the car ran 100% perfect the day before, is I also had the ECU rebuilt by Darryl Geller in Atlanta about a year ago. I wouldn't imagine that the ECU is already bad again but I guess it's not out of the realm of possibility. I know he has a guarantee on his work, but didn't want to blindly pull it and send it off again if that's not the problem. Perhaps I was doing something wrong with the voltage reading at the coil that I did first, but that number seems way off for the others readings seeming to be within spec. Also, when I tried to jumper the 2 terminals in the port in the engine bay to check for engine codes, the CEL never came on at all. No flashing lights on the dash or anything. If I recall, when I did this test a long time ago before sending the ECU off for whatever reason prompted me to do that, I could have sworn I got the CEL to flash before.
 
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