Help needed ASAP. Cutting out BAD.

[steve]

If there is a problem with this circuit to the ECU can relay be added to the circuit and just use the radio line as a switch for a good 12volt line?

I'm having similar problems and the radio circuit is the one that seems to be dropping off. I've seen the TPS jump with the motor not running and my ISC will work off and on by my logs.

If there is a problem with the MPI circuit you need to find it. It runs all over the engine bay so without finding the actual cause bypassing the MPI relay isn't going to help, the problem could just as easily be post MPI relay or pre. The ECU is just one more of the post device on that power bus.

Backup power varying should have no interaction with the TPS. Unplug the radio fuse and you see that other than loosing your fuel trims (and the settings you can't see) it doesn't have any impact.


I'm done here until there is some hard data.

 

[tyhoppy]

Thanks for your help. After all wires tested good, I replaced my ecu with the one from my eclipse. It seems to be running fine. I think i have a charging problem; my voltage readings are right at or around 14 volts, but It seems like my battery is slowly dying. I drove for a half hour yesturday and the battery died, lights went dim. So I replaced the alternator with one that I had tested to see if that is it. We will find out soon enough. Untill then I am going to carry a spare battery in the rear hatch area just to be safe. Thanks guys

 

[fourreGsixty3]

Not trying to kill you, but depending on the age of the battery, and from repeated dying of the battery it may need replacement aswell, but it could also still be fine. Please let us know if your problem was fixed.

 

[tyhoppy]

well I was getting the same reading on the data logger as i was getting with my voltage meter. and tonight on my logger i was getting reading ranging from 12.6-12.9 to 13.1-13.2 however i connected my tester to the battery and got a reading of a steady 14 volts. earlier i was getting a reading of 14 volts with my logger, but now I am not... will this affect anything?

 

[steve]

When your checking these, are you getting different values between a voltmeter and the datalogger or just getting different measurements at different times but consistent between the logger and voltmeter?

If it's different voltages at different times then it sounds ok because all of them are acceptable operating voltages depending on the state of charge and temp.