I have a 2001 Galant GTZ with the V-6 engine. The check engine light being on is keeping me from passing the emission test at the end of August. The codes are as follows: P0171-system too lean, bank 1; P0175-system too rich, bank 2; P0134-02 circuit, no activity detected, bank 1, sensoe 2; P0340-crankshaft position sensor A circuit, bank 1 or single sensor; P0335-camshaft
position sensor A circuit. I am really puzzled over all these and don't know where to begin to track down the problem(s). Car runs pretty good. Starts fine. Replaced the oxygen sensor and the code is the same as when the original sensor was installed. The crankshaft sensor was replaced when I replaced the timing belt about a year and 6000 miles ago. No codes before the routine belt replacement nor afterwords. These codes have been on for several weeks. The car does seem to run better when the ambient temperature is high, in the 80s and 90s. Not as good in the cold. I would appreciate any insight that can be offered. I don't want to go to a repair shop and be taken. Wondering if I could do the repairs.

 

I'm no expert but just a quick thought...

I would be shocked if all that stuff failed at the same time...

They all run to the ECU though so I would start looking there...
Check the connector make sure none of the pins are bent or corded, you can try some electrical contact cleaner and see if that helps.. Possibly just resenting the connector would help.

If not it's possible there's a problem with the ECU as well but you should probably have a professional look at it before replacing that.

 

Where is the ecu and its connector? The information stuff I have access to does not tell me that.

 

Like I said I don't know this car and I am not an expert but a quick Google search says it's behind the glove box (behind the blower motor and such)..

I would say you should get a service manual if you are going to be doing any work yourself.

 

I've got a Haynes manual, and it does help. Like many of these publications, the details that would be most helpful are left out, or just glossed over. This situation is just plain weird. My local Mitsubishi dealer closed up a few months ago, so the nearest dealer is around 30 miles away and in another state. Any other ideas would be appreciated.

 

I don't know how the Haynes manual could gloss over the location of the ECU... That's a pretty important part.

You might want to see if there is an official service manual from Mitsubishi, that might be more helpful...

You don't need to take it to the dealer for diagnoses of this problem but 30 miles isn't that bad... There are people that have to drive 500 miles to get to their nearest dealer.

You can call them (or even dealers further away if they won't help) and ask for advice on the problem and parts locations. They should be able to look it up in their service manual and tell you where it is if you get the right person.

 

On a thought I disconnected the battery since sometimes disconnection of power to an electronic device resets the defaults. I thought it was worth a try. Anyway, this seemed to get rid of the majority of the OBDII codes. What I had remaining was P0340 and P0335, the ones referring to camshaft position sensor and crankshaft position sensor. Might there be a problem with the timing belt position? Not enough to cause a real running problem, but enough to set off the sensors? Like a very slight stretch of the belt or tensioner problem, or slight mismatching of the cam pulley and crankshaft marks with those on the heads and block? Seems rather unlikely that the camshaft position sensor, being integral with the distributor, would go bad along with the crankshaft position sensor, which was replaced along with the belt not long ago. Anyone come across a similar situation?

 

I don't know for sure but I don't think the computer can report on a timing problem... I think it really only identifies a signal voltage outside the spec...

I'd still wonder if there was either a broken wire in there somewhere or a problem on the connector..

If you can get the connector out of the ECU you can test continuity.. I wouldn't attempt that with the ECU connected though.

 

I agree the computer probably can't recognize a timing problem and tell you there's a timing problem, but multiple sensors being "tripped" because of the signals being out of the acceptable parameters might point to a limited number of possibilities. I'm having a heck of a time getting to the ECU but I'll keep trying. After 14 years the plastic has gotten brittle and I really don't want to break anything if it can be avoided.

 

Can't you use a timing light to check the timing?