Cadillac Seville / Cadillac Eldorado Forum Discussion, 1994 won't idle, and runs away in Past Cadillac Vehicle Discussion; Okay,
My 1994 Seville suddenly wouldn't start the other day and I thought it was the Ignition Cylinder. I replaced ...
My 1994 Seville suddenly wouldn't start the other day and I thought it was the Ignition Cylinder. I replaced that and I was told that the only thing that would cause this issue is the ignition switch. So I replaced the ignition switch. Over the weekend the car started dying when it I slowed to a stop. And it would race away from me when I started it. I have replaced the Idle Speed control Motor a couple of months ago when it started accelerating away from me on the freeway. I didn't find any codes at that time but replacing the motor fixed that issue.
I am now getting the following codes:
P026 (E026) ......................................... Shorted Throttle Signal Switch
P095 (E095) .................................................. Engine Stall Detected
I found out that the CKT 427 wire from the white connector on my PCM which is supposed to be related to the TPS sensor connector is shorted out? However the wire at the white connector is pink but the wires at the TPS sensor are dark Blue, Green and black? I have no idea which one I need to replace. Also is there a way to check my TPS sensor via the dash diagnostic panel?
Alright, Pin number 8 on the white connector at the Engine Control Module or PCM or what ever you want to call it, connector is a primary wire that goes to the Idle Control Motor. It is pink and about 22 gauge which is ridiculously small for a wire that is so important. Checking that wire it at the ECM connector by setting my Multi Tester on 200k ohms and touching the wire and a local ground bolt I got a reading of 1.2 ohms and it should be well over 100 ohms so it was shorted out. So cut the pink wire about 4 inches from the plug on the Idle Control Motor and about 4 inches from the ECM plug and I replaced the rest of it with a 12 gauge wire running in it's own loom cover from the Idle Control Motor using just a simple butt connector and some shrink wrap. I had to punch a new small hole in the firewall behind the glove box next to the other wire harness that passes through at that location so I could run the new 12 gauge wire through down to the ECM under the glove box on the passenger sidewall.
The car still had an issue but I was getting a good 163 ohms or better after I replaced this wire. So I checked the connector at the Idle Control Motor. Testing between connectors A and B and then C and D I should have seen a resistance of about 40 to 80 ohms but again I only got about 1.5 ohms which meant that when the wire shorted out it took out the Idle Control Motor. The wires at the Idle Control Motor are pin A - black/white wire, pin B - pink wire, pin C - dark blue wire, pin D - light blue wire. Sooooo I had to go through the pain of replacing the Idle Control Motor which is quite a pain if you cannot remove the entire Throttle Body bracket. It requires you to at least remove the Air Intake hose, and the Cruise Control unit, which I should say is something you should be careful of because there is a really, really small vaccum hose that is attached to the Cruise Control that is actually hard plastic and easily breaks! Yes, I have to replace that when I get a chance.....
Everything works perfectly now. I will try and add a few picks of what I did. ECM Location.png ECM White Connector Pin 8.png