I just got a 89' turboII that has an autometer afm. It's not hooked up. Looked on the auto meter website and download inst. My question is..from peoples experience where do you guys hook your wires to? I know black is ground, but the red , white and especially violet. Should i splice the violet to the single black wire coming from the oxygen sensor on the downpipe?

 

Yes the purple goes to the O2 sensor wire, but you should source it at the ECU inside the car, not in the engine bay. It is not shield just before the ECU and you won't have to worry about getting the wire through the firewall or it burning on the exhaust.

Vince

 

I assume you mean an Air/Fuel gauge? AFM around here typically means "Air Flow Meter".

My meter had three wires. Black (ground), red (12V) and violet (O2 sensor). Not sure what the white wire is. Maybe you could post a link to your gauge so that we can figure out which model?

You can connect to the O2 sensor wire at the ECU. I could generally tell you which wire except you didn't post what car you have. In general it will be a gray shielded wire. You connect your meter to the inner wire and NOT the shield.

 

this is what i have.
http://www.autometer.com/download_instruction/837j.pdf
i have a 89 turbo II
So i should trace the black wire from the oxy. sensor on downpipe back to the ecu? Then just splice it in? Where is the ecu? I just got this car so bear with me. lol

 

OK. So white is to the dimmer switch.

The O2 sensor wire at the ECU is a grey shielded cable. You will make your connection to the inner wire.

The Factory Service Manual is in the FAQ and has all this info, including the location of the ECU.

 

Connect the purple signal wire at the ECU (pin 2C) where the wire isn't shielded. You can get switched power there too (pin 1B) and ground from either a ground wire or an ECU mounting bolt.

 

Umm... dumb ? what do you mean by "sheilded" wire.

 

In the engine bay the O2 wire is shielded, meaning there's a wire braid surrounding the signal wire to protect it from electromagnetic interference. One end if the shild wire is grounded, so intercepted interference is sent to ground.

If you try to tap into that wire chances are you'll contact the shield wire as well as the signal wire, so the O2 signal will be sent to ground and neither the ECU or the A/F gauge will get any signal.

Just don't go there...