What the hell is going on?

A friend and I did some work on my 88 TC today, and now it won't run right.

Take note, we only added a wideband, and changed the turbo components (header, turbo) and plug wires.

I already know that what we did is completely unrelated to the issue.


I can start the car, and it will run (really really bad). We initially thought it was the TPS, but the voltage was good. Then we checked the VAM, that was fine.

It runs at 500rpms, it can't rev over 3k without leaning out and detonating, and my vaccum is at -2

There are no leaks of any kind.

Now here is the strange part. We disconnected EVERY sensor (VAM, TPS, ACT, ECT, and O2) and it started up with the same symptoms...as if it wasn't getting any signal return from any sensors.

Something else I noticed that was new is that the fuel pump and brake booster won't shut off when I turn the key, as opposed to shutting off once the system is primed.

I think this has been an on-going issue since my car has been progressivly getting worse over the weeks (stalling out, random power loss, strang misfires after boosting).

I'm hoping my Ignition switch has something to do with this, but I really don't know and I don't want to throw parts at the car.

Can someone help?

How much of this is new, just started since yesterday and how much of this the ongoing issue.
Have you checked for a loose/disconnected harness connector? Pulled codes? What kind of vacuum do you get it you hold idle around 1K?

Did you check voltages. You say the TPS and the VAM are OK but you don't think any sensor has sig return voltage? Did you check with a meter

Is it possible the plug wires were mixed up?

I had an injector stick wide open and take out the headgasket the moment I added a wideband. Strangest thing I ever saw....

Are you running the wideband as a stand alone or do you have it in the factory 02 spot running a simulated narrow band? Did you cut any wiring to make it work?

Vacuum is very low. My cam usually runs with 10in of vacuum, but ever since last night, if I hold it at 1k, it's around 3-4in.

We disconnected every sensor, and the car ran exactly the same. We checked every ground and cleaned the contacts just in case.

We checked the ignition switch, and it's not working properly.

Another weird thing, my dash gauges won't turn on when I put the key to the run position, but if I just turn it to the "start" position, they will turn on and work fine.

I've had a wideband in my car for 6 months, but this one took a crap when I crashed into snow, hence the new one.

I triple checked the plug wires, and they were all correct.


My timing (WITH THE SPOUT PLUGGED IN) is 10 BTDC, and it stays there when I rev the engine (as if the SPOUT was unplugged).
Either my LA3 fried, or something else is not letting the EEC get a return signal from any sensors.

i doubt your computer is fried, something big is not getting a signal, thus why your not getting any timing advance.

Orange wire that is a ground and hooks onto the turbo compressor housing? Jus throwing out ideas.

I assume the WBO2 bung was welded in? Did you use a MIG or stick welder? If so, what precautions were taken to protect the electronics from voltage spikes?

Fuel pump always running and engine running like total crap is often a sign of a fried PCM.

Much or all of the sensor VREF and SIG RETURN circuits must be intact since you were able to set the TPS voltage.

Originally posted by bang4thebuck:
Orange wire that is a ground and hooks onto the turbo compressor housing? Jus throwing out ideas.

+1
I was just about to say that. Also check the VAM to turbo hose. Sometimes from the top it looks completely connected but the underside is open and send the wrong air message to the computer. Next I would use the string method to check the timing.

Ircm!