Hello,

I have a 1993 945T with 125K. Just got the codes 2-3-1 and 2-2-1. I'm trying to figure what to do next. The FAQ has info on these codes and indicates that the AMM, O2 sensor, and computer were replaced in order to fix it. I am hoping that all three parts are not what is needed in my case. The car has had the following symptoms recently, although somewhat intermittent:
1) Could not accelerate past ~4500 rpm on freeway, full throttle, (~70mph in 3rd gear). However, if I backed off the throttle, it will accelerate fine to >80mph (at lower rpm in overdrive). Oddly, this symptom seemed to go away when I changed the oil (from 10W-40 dino to 10W-30 mobil-1). (I had used 10W-40 for three quarts while I figured out where an oil leak was coming from (distributor shaft).)
2) Lots of pinging (knocking) even with 93 octane, and just half-throttle.
3) Gas mileage isn't that bad - about 20 mpg on highway with a big load.
4) Sometimes there is hunting idle and stalling on startup. Happens about 1/5 times on startup, and more often when the outside temp is 60-70F.

The distributor cap and rotor were just replaced and the oil leak fixed. Then I drove the car hard, which I hadn't done for a while, and noticed the symptoms above. The next day (after about 300 miles) the codes appeared when I started the car. I have reset them under the hood a couple of times but the check engine light comes on as soon as the car is started and gives the same codes.

FYI: I replaced the fuel pressure regulator, knock sensor, crank position sensor, power stage in the last 2-4 years. The O2 sensor is original, as far as I know. The air filter looks clean. I don't see any obvious vacuum leaks and the turbo gauge is indicating a good vacuum at idle (the same needle position that it has had for 4 years at about 2/5 the way between all the way left and center.)

Thanks,
Steve

First, original O-2 sensor? Mine lasted a loooong time but I think you are pushing it at this point (what are the V readings during operation?). That is what both those (fuel injection) codes relate to. Bad fuel trim due to a bad signal from O-2 sensor. You can check the sensor out of the car with a propane torch & voltmeter. Not overly accurate but it at least tells you if it is functioning.

Next, look over what you have recently done and see if there is a problem there. Could the Dist. cap be slightly out of position? The rotor?
Are plug wires properly routed? Are they arcing? Properly seated & connected?
Is the distributor aligned properly so that the rotor is pointing to the correct post whist firing (you mentioned the distr. oil leak which can get screwed up if you miss an item during reassy)? Any chance you reassembled the distr. drive 180 degrees out of phase? Don't know if it will run in that case but stranger things have happened.

Next check the connector at the knock sensor, make sure the connectors are fully seated in the carrier or they may not make good contact. Something there is wrong if it is knocking as badly as you describe. Properly functioning, you should not hear any pinging.

--
1999 E320 1994 F150 1989 560 SL 1986 560 SL (deceased) 1988 300 TE (departed) 1994 945T (daughter's) 1988 244DL (fallow) 1986 242Ti (fallow) 1968 GT500KR (under restoration)

Thanks. My mechanic did the distributor rebuild (I had thought that I had a rear main seal leak, so I took it to him, but it turned out to be a distributor leak). As you say something might have gone wrong there, so I will check it out since it is a long way back to my mechanic. The timing seems okay. About 15 degrees at idle. Perhaps the distributor needs to be turned a bit. I cleared the codes (needed to disconnect the battery to prevent the codes from re-appearing right after startup.) I have an O2 sensor on order too.

Thanks
Steve