99 Subaru Impreza OBS random codes and now a awd problem?

[harveyj22]

I am completely lost... went to Advance and had it put on the computer and was told it was an O2 sensor, changed,  pulling out and push the gas and pull out at 5mph regardless of how much gas I give it. Suspected throttle position sensor since Advance now says they can't check the codes cause it wasn't hooking up. We buy our own code machine and check again and get that the knock sensor needs changed, husband tries to drive it to see if the TPS is fixed and AWD locks down and there's a clicking noise he feels is the acuator now. This just seems like a total spiral to the death of this car and it's just under 150,000 miles! HELP!!!

[Fairtax4me]

Year? Model?

Sounds more like the alternator is dieing. Low voltage causes all sorts of problems ECU needs electricity to work, not enough juice and it doesn't work right, starts throwing codes.

Have the battery charged and the charging system checked.

[lmdew]

If it is your alternator, go to Subaru as they have the alternators prices right as there was a rebuild program on them a few years ago.  Worth checking. 

[harveyj22]

Funny funny little car. I took it to Subaru cause my husband swore it off by the time it went nutty. They said the new throttle position sensor we installed caused the computer to need to be reset. Basically the computer was totally thrown off by the new sensor and decided that everything must be broke because of this new part. Long story short, they reset the computer and it's running like a new machine, $92 later. Not the cheapest fix but at least it wasn't what I thought it was going to hit me for.

[Fairtax4me]

That's pretty cheap for an hour labor these days.

Had you mentioned replacing the TPS before I would have said that needs to be calibrated first. The ECU uses the TPS as one of the main controllers for fuel and spark timing. And the Trans control unit uses it for shift point timing and AWD lockup.

 

Glad they got it sorted out for you.

Which dealer did you take it to?

[1 Lucky Texan]

I wish I could get a trustworthy, capable 'someone else' to do anything significant on my cars for under $300-$500

 

you skated at just $92

[ivans imports]

try titening up the main engine ground on ps top of intake and check that all engine main harness conectors are pluged in all the way and clean posts on batt mabee extra ground wire from - post to block

[harveyj22]

Yes Su bah roon, I did tell them that we had replaced a TPS and they were booked up for the next 2 days but when we told him we'd changed it he said he knew what it probably was. Said the computer needed reprogrammed to connect the communication between the mass air flow and TPS.

Lucky, I just took it to my local Subaru dealer. I don't know anyone here locally that I can trust. I took mine to a guy that said he had 2 subarus and loved to work on them. I learned very quickly that even as a mechanic he had no clue. He over filled all my fluids and took forever to put in a timing belt. Don't get me wrong it's a long job but he took forever. If it's something big that my husband isn't able to fix then I take it to my dealer. I've only taken it to the dealer twice before this, once when I first got it for another altenator because the place that sold it to me put some industrial cleaner in it and shorted it out. Then again for a recalled part in the evap system that caused a carbon backup that had to be chemically burned and forced out. Thank God it was a recall or I'd never have been able to pay for all that. We have a very reasonable local dealer, it's cheaper than the otehr ones in the area by about 25% usually.