total loss of ECU power

[turbohounds]

Please help if you have any suggestions - I'm desperate here. My '92 Talon is stalling, it seems the ECU loses power (either lots of clicking, or one click, and I have to wait until it will start). Everything else works (except maybe the SAFC, which is one the same circuit I think). The problem is episodic - lots of times in a week, then goes away for 6 months. It has been there since I bought the car stock. What I've done in an attempt to solve the problem, or might be related:

Changed the capacitors in the ECU (old ones were fine)
New ignition coil
New power transistor
New battery cables
New cam position sensor
Different MAS/2G MAS
New ignition switch
Cleaned all starter connections, added new engine grounds

I'm out of ideas - seems like a relay, but I have no idea what that might be. It is very bad when this happens in rush hour traffic - I have to figure out what is in the ignition circuit that is wrong.

 

[speedytalon]

If you have access to another ecu I would try that first. Even though your other one looked fine. It sucks that its a problem only some of the time. I would first try another ecu though. That is the best place to start considering that you have replaced just about everything else. when the car is running without this problem, how does it run? does it idle ok and all that?

 

[turbohounds]

It runs just fine normally, even right before and after. Friday on the way to the dragstrip it died, and we were considering not going. It died on the line on me, ran a measly 14.1, my wife came back and ran a best ever 13.22. It's frustrating it is so intermittent - I could borrow an ECU from a friend, but I might not know for 6 months if that was the problem. Short of buying a spare,

If that is my best bet though, I'm willing to go there.

 

[pinknuggit]

The same thing happened to one of my buddies when he got his dsm together. He didnt get power to the ECU, AFC, or the fuel pump.

 

[67goatpimp]

when my ecu shit itself there was nothing visibly wrong with it, but it clicked like you are talking about and it smelled fishy (i mean that in the most literal sense)

 

[turbohounds]

The same thing happened to one of my buddies when he got his dsm together. He didnt get power to the ECU, AFC, or the fuel pump.

Did he ever figure out the solution? My fuel pump (and starter for that matter) always runs, so that circuit is working. The ECU looks/smells fine, but I admit that is far from diagnostic.

 

[pinknuggit]

No, but i advised him to physically check the wires to make sure they did not disconnect anywhere.

 

[mr2gixxer]

Was this problem ever solved. Finally, someone that has the same problems as i do. PLease help some fella DSMer's out when you figure out the problem, please post and share.

 

[Booster2k]

Try the relay passenger side of ecu little gold box with connector, its the ecu/fuel pump relay, you can bypass it if you have a schematic I had to do it to mine, ended up being ecu because thats what provides ground to that relay.

 

[turbohounds]

Try the relay passenger side of ecu little gold box with connector, its the ecu/fuel pump relay, you can bypass it if you have a schematic I had to do it to mine, ended up being ecu because thats what provides ground to that relay.

I replaced the MPI relay with no change, then changed out the ECU for a rebuilt unit. First few tries it wouldn't fire, then all was well for a few days and the problem disappeared. Then my timing belt decided to shed a few teeth and none of this mattered.