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Toasted ECU!!!! stipid old electronics

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Old Aug 13, 2002 | 04:01 AM
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slidingsky's Avatar
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Toasted ECU!!!! stipid old electronics

I burnt my frickin ecu today. Drivin as usual,broken tps. car started buckin and stalled continuiously. Finally got movin and drove hard, still bucked. Got kinda curious and redlined in neutral, still bucked then shot all the way to 8k. let back down and drove home. Halfway home the car stalled and wouldnt start. Poped the hood and noticed the wire going to the main relay smokn. Didnt blow the 30A fuse but it was hot. Towed home and followed the wire. Its melted very bad and according the FSM it goes straight to the ECU. I dont think there is any way in hell the ECu survied that. Plus wires needs to be replaced. I think Im going with a weber and a dist. This stinks. I have a TII and thought about just dumping the NA but Ive put too much time into it. I think the weber will be kinda fun.
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Old Aug 13, 2002 | 04:10 AM
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Re: Toasted ECU!!!! stipid old electronics

Originally posted by slidingsky
I burnt my frickin ecu today. Drivin as usual,broken tps. car started buckin and stalled continuiously. Finally got movin and drove hard, still bucked. Got kinda curious and redlined in neutral, still bucked then shot all the way to 8k. let back down and drove home. Halfway home the car stalled and wouldnt start. Poped the hood and noticed the wire going to the main relay smokn. Didnt blow the 30A fuse but it was hot. Towed home and followed the wire. Its melted very bad and according the FSM it goes straight to the ECU. I dont think there is any way in hell the ECu survied that. Plus wires needs to be replaced. I think Im going with a weber and a dist. This stinks. I have a TII and thought about just dumping the NA but Ive put too much time into it. I think the weber will be kinda fun.
Open up the ECU and look at it. It'll be pretty easy to tell if its fried or not.

Fuses get hot normally. I doubt any damage occurred to the ECU itself.

Wires don't burn unless they have more current running through them than they can support (IE: a short). A wire should only smoke if it is running a bigger fuse size than stock, or is damaged.
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Old Aug 14, 2002 | 06:38 AM
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Thats what I dont get. The fuse is exactly what the lid says. The wire got hot enough to melt the insulation off but didnt blow the fuse. As far as I can tell, w/o taking the dash out, the wire is burnt from the batt to the main realay, and out into the firewall. Ill probally need to pull the wire harness to check it. The ECU isnt the problem. I can get one used for less that $100. The harness is going the be the problem.
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Old Aug 14, 2002 | 07:26 AM
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You might be able to fix the ECU. Open it and look for a burnt resistor. Note the colors on the resistor and then use the below handy-dandy Resistor Calculator to determine the value.

Notice: This program is not free. It is BeerWare. If you like it, have a beer.

http://members.***.net/miclam7/rescalc.zip
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Old Aug 14, 2002 | 10:04 AM
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I just went trough the same thing, except that the previuous owner put a fuse that was too big into the EGI comp. terminal.
I popped the ECU open and didin't find anything that looked burnt, so I put it back together.
I am in the middle of replacing the "Front" wiring harness now.
I hope nothing else got messed up during the short (i.e. the engine harness, ECU, etc.) I have unwrapped the engine harness quite a bit and have not yet found melted insulation like on the front harness.
What fuse blew on your car? What relay?
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Old Aug 14, 2002 | 01:02 PM
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I wish I was driving!
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Originally posted by cblake3
I just went trough the same thing, except that the previuous owner put a fuse that was too big into the EGI comp. terminal.
I popped the ECU open and didin't find anything that looked burnt, so I put it back together.
I am in the middle of replacing the "Front" wiring harness now.
I hope nothing else got messed up during the short (i.e. the engine harness, ECU, etc.) I have unwrapped the engine harness quite a bit and have not yet found melted insulation like on the front harness.
What fuse blew on your car? What relay?
I had a huge engine wiring problem and melted together almost every wire in the ECU/EGI harness. I just replaced the harness, and all ran as planned.
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Old Aug 18, 2002 | 04:08 PM
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The fuse closest to the engine. Its supposta be a 30A and thats whats in it. The main relay. Its harness is all melted together. Well now that I think about it I should get a new one of those to. Well guys Ive decided to go carbd with a dist. I dont expect a big HP increase. Ill post in a couple weeks on how everthing goes.
Sky
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