Flash ECU O2 Sensor Issue

[mb3000]

Just wanted to thank you again Greg for all of your help.

Was so disappointed yesterday that I forgot my manners. Sending ECU back this Mon. to get serviced. Don't know when I'll be able to work on the car again, looks like around Thanksgiving time.

[Greg E]

Nah man I'm sorry you the thing didn't work out of the box for you.

[mb3000]

Just an update if you (or anyone else) is curious.

Adam was very professional throughout our conversation back & fourth about the ECU. He checked out the ECU and said it was an earlier model, that had overspray on the O2 pin jumpers before he could test for that condition. A new unit should be shipping out early this week.

Hopefully I don't have any problems the second time around

[Greg E]

Awesome!!! I'm glad Adam was able to help you!!

[mb3000]

Greg, hate to bother you with another question.

What is the most important power source for the ECU during flashing? I would like to wire up an AEM Voltmeter Gauge to that wire so I can check the volts more easily.

[Greg E]

The flash wire is the wire you want constant/steady voltage into. I'm not sure putting a gauge inline to that wire is a good idea. That gauge will draw current.

[mb3000]

Now that you mention it, that sounds like a recipe for a bricked ECU! I guess I'll just measure battery voltage instead (need to fill the last opening in my gauge pod ).

[99 vr4]

FYI, you should measure the voltage coming from IG1 to the ECU. Pin 82 on the 1G / 2G ECU plug. This is the large plug on the right, bottom row, first pin on the left (looking from the wire side of the plug). IG1 supplies power to the ECU via the ignition switch, telling the ECU to turn on the MFI relay. During flashing, the MFI relay is turned off by the flash routine. This is why when you flash a running car the car shuts off to flash.

[CoopKill]

Thinking I may have a similar problem with the o2's. Will update my flash thread.