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Bad ECU? How do I check my brainbox...

2479 Views 18 Replies 10 Participants Last post by  Gypsy_Botanist
I was driving the other day and shortly after I got fuel, my tac, speedometer and all of my gauges went dead. I thought/hoped it might be a loose fuse & continued to drive her for about an hour and then I started to loose a little power, she just couldn't maintain 75, I was driving on the highway, and slowed to about 60 with the same amount of throttle on level ground. Then all of a sudden she starts kind of chugging or gives a shudder, a few seconds later she backfires and I lost all power. She died when i took her out of gear, or maybe I turned the key off. After I got her stopped I tried to start her up, and got nothing. The fuel pump turns on and the engine cranks and turns over but no fire (I've not checked the plugs for fire yet so only 90%). I also have no check engine light, not even when you turn the key or for the few seconds it turns on after starting. I tried turning the key thrice to see if she is throwing any codes but I got nothing. So i think the brainbox is dead I just don't know how to test it. I thought I could plug an OBD computer into it but I don't know where to plug it in at, or any other ways to diagnosis it. I'm going to get a relay checker and check all the relays and fuses under the hood. If anyone has any other ideas about whats wrong or how to check your brain box please let me know.

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I would not condemn the brain when you stated that all the guages, etc. went dead. You should not trust the CEL when the rest of the cluster does not work.
True words.
But you need to verify power to the ecu first up. There's another fuse panel (a PDC) under the hood that has stuff.

Im not convinced it's your computer (although there's a chance it might be) by the symptoms and this early in the diagnostic.

I'm not going to write a book right now 馃檪
The random 鈥渂ackfire鈥 you mentioned

Classic symptom of water in the fuel....if it鈥檚 been sittin a while with ethanol-laced fuel that is a possibility

But follow the other steps first. No spark won鈥檛 fire either water OR fuel.
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