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Discussion Starter #1
after some small diagnostics at fuel tank pump area, car doesn't start.
no spark. all basics check fine.
i'm suspecting I fried the IGNITION E.C.U.
IS THERE A BASIC CHECK TO BE DONE TO THE ECU'S?
any help is greatly appreciated.
thanks, Charlie.
 

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no, you can't really do anything yourself other than to make sure the plug pins are clean and fitted correct.
you could send it off to a ecu doctor to have it checked, probably for 50$ thereabouts.

what exactly do you mean by 'all basics check fine'?
(flywheel sensors, relays, rotor, coil connections and cranking voltage all checked fine?)

and what makes you think you "fried" the ecu?
 

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As far as I know, there are no tests for the ECU itself. Best I can suggest is to check everything else until the only thing left is a faulty ECU. See the link in my signature (you first have to click on 'show full signature') to a page of DIY info for L-jet diagnosis. That said, the ECU's are usually quite reliable. An iffy ground connection or faulty flywheel sensor is way more common than a faulty ECU.
 

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Discussion Starter #4
no, you can't really do anything yourself other than to make sure the plug pins are clean and fitted correct.
you could send it off to a ecu doctor to have it checked, probably for 50$ thereabouts.

what exactly do you mean by 'all basics check fine'?
(flywheel sensors, relays, rotor, coil connections and cranking voltage all checked fine?)

and what makes you think you "fried" the ecu?
no, you can't really do anything yourself other than to make sure the plug pins are clean and fitted correct.
you could send it off to a ecu doctor to have it checked, probably for 50$ thereabouts.

what exactly do you mean by 'all basics check fine'?
(flywheel sensors, relays, rotor, coil connections and cranking voltage all checked fine?)

and what makes you think you "fried" the ecu?
 

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Discussion Starter #5
thanks for the response. All was finally fine after car sitting. have replaced both crank sensors and a couple temp. sensors after checking faulty. put all back together. I had been working on tag lights and started messing w/ wiring at harness at trunk hinge area w/ previously burnt wires.
all was fine, repaired fuel guage level and low level light indicators. I was suspecting that I may have been testing incorrectly at the fuel pump area, using the battery directly to supply my 12v + feed.
now I have no spark. relays APPARENTLY check ok, coil ok. the crank sensors are a year old..….Do you have a source for checking the ecu? thanks very much.
 

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Discussion Starter #6
As far as I know, there are no tests for the ECU itself. Best I can suggest is to check everything else until the only thing left is a faulty ECU. See the link in my signature (you first have to click on 'show full signature') to a page of DIY info for L-jet diagnosis. That said, the ECU's are usually quite reliable. An iffy ground connection or faulty flywheel sensor is way more common than a faulty ECU.
 

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Aren't there some known sketchy ground connections around the ECU?
 

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Discussion Starter #8
thanks for response.
i'm working from the old Int.auto parts book #9129.engine maintenance manual .1982-84. Mine is an 03. some of the real(?) diagnostics are beyond my expertise, but the car ran fine 'till i had to check the fuel guage connection at the trunk internal fuel pump. now no spark. all normal checks are ok. that leads to as you said...'it's gotta be the ECU'
 

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Good to know.
I'd poke around the area you last worked in. Unplug and plug back in every connector you see. Inspect them closely.
 

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Discussion Starter #12
that's all I've been doing. thanks.
I guess that's why I've been so resigned (and helpless) that it must be the ecu.
i'm rechecking w/ new enthusiasm 'all that went before'.
thanks again....best advice.
 

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there is nothing -that I can think of- connected with the in-tank pump or rear lights or trunk hinge that would cause a no spark...

a few basics I'd do:
charge your battery fully (you might have run it down with all the testing)
then check voltage whilst cranking the engine (you need about 11V "whilst cranking" or the ECU will not work)
check for 12V at the coil with key on
 

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I have no experience with Spider ECU's but I do know how they work on V6's and they may be similar. The ingintion ECU only phase shifts the incoming signal and applies a rev limit. The only input that it needs is the signal from the ignition sensor. A Milano or late type GTV6 will run with the ignition ECU bypassed. The timing will always be at max and there will be no rev limit and the motor may be hard to start but will run OK. They are easy to test with a signal generator and an oscilloscope provided you have the connection information.
 

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Discussion Starter #15
I have no experience with Spider ECU's but I do know how they work on V6's and they may be similar. The ingintion ECU only phase shifts the incoming signal and applies a rev limit. The only input that it needs is the signal from the ignition sensor. A Milano or late type GTV6 will run with the ignition ECU bypassed. The timing will always be at max and there will be no rev limit and the motor may be hard to start but will run OK. They are easy to test with a signal generator and an oscilloscope provided you have the connection information.
 

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You'll find the issue, and I suspect it will not be the ecu.

A nearly identical situation happened to me this summer. I was fiddling with the fog light switch on the console because the rear fogs didn't work. I disconnected it and cleaned the contacts, etc, and reinstalled. Then went to start the car - nothing. I too worried that maybe I fried something in the ecu. It took me ten days of replacing fuel pumps, testing, then retesting, and testing again just about every sensor, valve and relay. Then, just by chance, I looked down into the TTS connector and noticed there was only one shiny contact looking back at me - the other had slipped down into the wire casing, out of site. I fished it out, reconnected and ten days worth of angst melted away. Had nothing to do with the fog light switch, just a coincidence.

The point I'm trying to make is that your work in the trunk most likely has noting to do with your ignition problem. Unless you were probing around the fuel system wiring using an ohm meter, I shouldn't think the ecu was affected. I'd focus on all wiring and connections downstream of the ecu. Good luck.
 

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Discussion Starter #18
You'll find the issue, and I suspect it will not be the ecu.

A nearly identical situation happened to me this summer. I was fiddling with the fog light switch on the console because the rear fogs didn't work. I disconnected it and cleaned the contacts, etc, and reinstalled. Then went to start the car - nothing. I too worried that maybe I fried something in the ecu. It took me ten days of replacing fuel pumps, testing, then retesting, and testing again just about every sensor, valve and relay. Then, just by chance, I looked down into the TTS connector and noticed there was only one shiny contact looking back at me - the other had slipped down into the wire casing, out of site. I fished it out, reconnected and ten days worth of angst melted away. Had nothing to do with the fog light switch, just a coincidence.

The point I'm trying to make is that your work in the trunk most likely has noting to do with your ignition problem. Unless you were probing around the fuel system wiring using an ohm meter, I shouldn't think the ecu was affected. I'd focus on all wiring and connections downstream of the ecu. Good luck.
 

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Discussion Starter #19
thanks, you're right. keep it simple. consider the basics 1st.
appreciate you taking the time.
 
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