TCU code 23 after collision

[diggler1971]

I've got a 92 legacy awd (my son's car) that was in a wreck recently. It was hit in the drivers front side, my son pulled out in front of someone. Since the accident, the car will start up just fine, but runs for only a couple seconds then tries to die. You can rev and feather the throttle and sort of keep it running, but it continually tries to die. The car was hit pretty hard, bending the strut and wadding up the fender. I have replaced the strut and removed the fender, and I'm looking over the wiring looms that run down that side (under the fender) looking for crushed, pinched or shorted wires, but everything looks good so far. I noticed that the power light is flashing, so I checked the codes, and for current codes got a 23 (engine revolution signal). For the previous codes I got 23, 32,33. The 32 and 33 are VSS 1 and 2. I did put a tranny in this car about a month ago, so the VSS codes may have been from then, however I don't remember the power light ever flashing before.

So, does the engine revolution signal code refer to the crank position sensor or a cam position sensor? or both? It seems like either of these would produce this kind of effect, but I would think that the CEL would be on, and it's not, so far. So I'm not sure if this is a tranny problem or an engine problem.

I'm gonna continue to troubleshoot, but thought I would try to get some advice from you guys. So, any input is appreciated.

Thanks

[diggler1971]

Yes, the CEL is working when the ignition is turned on. But it is not coming on while the car is running. What I don't really understand is, if the engine rotation signal is not showing up, then how is it running at all. Unless the sensor is sending the signal to the ecu, but the tcu is not getting it, and trying to shut it down. It runs sorta like when your running out of gas. Choppy like that. If you don't keep it revved it dies straight away. I was however, able keep it running sort of steady when I had it revved at about 2200 rpm. When I ran it a few minutes ago, it ran the same as it has, but the power light is not blinking. I think the power light was only blinking when I was trying to drive it. But it still show the 23 code as current.

[Matt Monson]

I deleted your duplicate thread from the Engine forum. Please don't cross post. One location is more than ample.

[tahiti350]

power light flashing is a TCU fault, not and ECU. need to run the TCU self test (search for TCU test). It's easy and may provide more insight....

[Legacy777]

The ECU has an output Engine revolution signal it sends to the TCU. This is what the TCU is cranky about. The wiring will be up under the dash. Maybe something got jarred loose in the accident.

Even if you're not getting a CEL, I'd check the ECU for codes, and the clear both the ECU & TCU, and see what codes come back.