91 tt. I need help. Think my ecu is bad - 3000GT/Stealth International Message Center

Haha0624 · 11-13-2012, 02:32 PM

I bought my car a few months ago. It was running very good then last month my car started bucking and idling rough but it would only do it for a minute or two and then be fine... Now it's rough idle and runs on only 4 cylinders.. I did the good old volt meter to check ecu codes.. I got a 53 no fire on 3&6, ptu bad, check wire harness... I opens the ecu and found no blown caps just one that was loose. So I threw some soldier on it. Fixed the car for about 30seconds and it went back to shit. At the same time I notice the ecu had already been remand. Now even when I put new caps in the ecu the car still runs like shit.

Is there anyone in Illinois that has a known good ecu that I could borrow.i could pay alittle money to rent it.

Any other help would be greatly appreciated. Thank you

Hot943kGT · 11-13-2012, 02:51 PM

Hey, disconnect the ECS controller and see if it runs right. Ecs controllers go bad like ECUs do and send bad signals to the ECU.

Haha0624 · 11-13-2012, 02:58 PM

It's already disconnected and I have a new ptu..

Hot943kGT · 11-13-2012, 03:38 PM

The only other thing I can think of off the top of my head that made my car run as you describe was the fuel relay. It gets corroded and the fuel relay ends up sending a weak signal to the fuel pump and in turn your car runs like a heap... If I can remember anything else, I will chime back in...

Nater3kgtVR4 · 11-13-2012, 03:49 PM

Quote:

Originally Posted by Hot943kGT

The only other thing I can think of off the top of my head that made my car run as you describe was the fuel relay. It gets corroded and the fuel relay ends up sending a weak signal to the fuel pump and in turn your car runs like a heap... If I can remember anything else, I will chime back in...

I agree, Check the MFI relay on the interior passenger side of the center console. Also Check all your fuses that is usually square one.

Haha0624 · 11-13-2012, 08:09 PM

The Mfi relay deals with the injectors.. How would that cause no spark to 3&6. If I remember correctly the last time I did a volt check on the #11 pinout on my ecu I got little to no voltage even when getting the rpms up to 3000.. I am just lost.. There was a time when I had the ecu plugged in to the car with the cap off and I could wiggle or even hold one of the capasitors a certent way and the car would try to run better

lawdogg · 11-13-2012, 08:16 PM

Sounds like a bad driver on the circuit board. Get in touch with rymer21280, he is the ECU man.

Haha0624 · 11-13-2012, 08:26 PM

I'm half tempted to just eat some money and get the vr4 clone ecu... Does anyone think that would be a mistake on my part

lawdogg · 11-13-2012, 11:02 PM

What is the VR4 clone ECU?

CHRIS75 · 11-14-2012, 12:44 AM

Quote:

Originally Posted by lawdogg

Sounds like a bad driver on the circuit board. Get in touch with rymer21280, he is the ECU man.

Do this man specially by the symptoms you describe. He has worked on many of our ecu's, really great, fast and low cost too.

Sometimes caps can look good but they may be already messing around.