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91 Eclipse won't start

2276 Views 11 Replies 7 Participants Last post by  DirtyRat
Trying to help a friend get his daughter's 91 Eclipse to start. The car sat for a little over 2 years before he got around to having the head sent out for machining. Appearantly it was having valve problems of some sort. Anyhow, he got the head back, put a new gasket on, and timing belt, has done it all by the book (Haynes, *shiver*) and it cranks but won't start. I wasn't there when he initially fired it up, but he claims the fuel pump ran, and it made one attempt to start.

I looked at it the other day and we've got no spark, no switched ground to the ignition coil, no fuel pump prime, codes won't flash, and I can't communicate with the computer using a Snap-On Modus plugged up to the connector by the fuse block. Unfortunately the Haynes manual has some very crappy wiring diagrams, so they're not much help. And I can't make much sense out of a 8 wire fuel pump relay. Being a Chevy tech, I don't see optical crank or cam sensors either, so I wasn't entirely sure how to check the sensors with the tools he had. I did notice that the TPS sensor is turning on a test light dimmly, which tells me it's probably getting the 5 volt refernce from the computer, but everything else the computer is doing makes me think it is fried. Ideas? Suggestions?
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Coil packs maybe? Spark plug wires/spark plugs? I know it may sound stupid and newb stuff but most of the time the simple stuff like this is what causes the problem. Just a suggestion though.
Pull the ECU, they are notorious for leaking and causing damage. It should be repairable.
Cars need 4 things to start; spark, fuel, compression and timing.

Take off the return line on the fuel pressure regulator, try to start the car for a second. Does fuel pour out? If yes, continue.

After cleaning up the fuel, pull some plug wires off the spark plugs and again get someone to start the car. Do you see any spark coming from them? If not, check wiring, then replace coil pack and or power transistor. If yes, continue on.

Do a compression test. If in single digits, return head to machine shop and throw through his front window.
OddRob said:
Pull the ECU, they are notorious for leaking and causing damage. It should be repairable.
I don't quite follow you. What do you mean 'notorious for leaking'? The computer (ECU) on this car is tucked under the dash behind the radio. Are you saying I can pull the ECU out, take it appart, and visually see a problem? If that's the case we'll try that.

And no there's no spark or fuel pump running. While we haven't done a compression test, we weren't going to worry about that until we had both fuel and spark. My friend said he put the head & belt on following the directions exactly, so I'm confident he got that rigt.
Yes take it out, open it up and visually inspect the 3 capacitors towards the center of the board for leakage.
power transistor missing after head removal, or plug is loose? Right below the electrical plug for the coil pack, small black box with a flat plug .
Get in the car and smell near the radio. If you smell a rotten seafood smell or a old AV equipment type smell, the capacitors need replaced. That is what I was told. The ECM is located behind the radio.
I agree with the majority. Sounds like an ECU issue.

Pulled the ECU out, and took the lid off. Immediately hit with that burnt electrical componant smell. Looking at the 3 capacitors in the middle, they appear ok. But right beside the middle cap (which lays horizonatally) there is what appears to be a diode and it's burnt up (black all around it, this little diode lays beside one of the legs of the middle capacitor). Is this a fixable problem? Or is a replacement needed?
Its more then likely repairable. You can send it in for an estimate if you wish.
My friend picked up a junk yard ECU for 50 bucks, took it appart and smelled no foul smells nor did he see any burnt components. Installed it into his car and it started right up. Many thanks fellas. He's got a few other quirks with it right now, but I think a fuel filter and a good hearty drive can clear 'em up. Thanks again.
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