Heres the scenario. my legacy has run strong until just recently and is extremely hard starting, but when warm...it runs better, but still "loud" knocking and rough. up to half throttle, the car will consistently BOG down...until about half then it accelerates as normal. with the car not running, but the ignition ON. if I depress the throttle, I hear a steady Buzzing, which increases as the throttle increses. It is coming from the back end of the engine, or transmission/transaxle.....I can NOT pinpoint it. I pulled codes, and originally got a bad 02 sensor which I replaced, as well as replacing the purge control solenoid after reading that code. However, I am still receiving the TPS code, #31 to be exact. I have reaplaced it with a junkyard tps..and it is still doing the same thing. Not sure if the tps is the problem now. what are the chances of 2 tps, being bad, from a junkyard, out of a fairly new car.

 

questions, on this whine..or is the tps simply causing this, in a sensor down the line, most likely in the rear of the engine, or trans...

any thought?

Did you read my post in your other thread?

on my 1992 legacy, I have gone through the codes and replaced 02 sensor, purge control solenoid, and TPS(and set it to specs). Now the car runs a little smoother, but is still rough speaking from before my check engine light came on. I have little or NO power from about 1-40 mph. it literally wants to die. once I get past 40 mph, it runs like its brand new. Since this...my exhaust has been a little louder (could cat-converter being bad, create this HUGE decrease in power?) I am literally stumped.....pulled codes again, and it checks out perfect...but I literally can't back out of my driveway. If I get enough runway to get up to speed..the car runs perfect.....after 40 mph or so, as I said before.

could the VSS also be causing this...or does it sound strictly exhaust?

 

THoughts....?

you guys have been great at helping me, soo far with hte electrical side of things soo far...I appreciate it immensely.!

Please refrain from posting several threads pertaining to the same thing. Please keep them in one thread, and if your existing thread is not quite on topic for what you want to post, but still has info in it...please link to it in your new thread

 

Thanks

 

http://www.ultimatesubaru.org/forum/showthread.php?s=&threadid=13564

I think if your cat was plugged the opposite behaviour would be seen, i.e. power loss when giving it a lot of gas, not when going slow. You can test for a plugged cat by screwing a pressure gauge into where the O2 sensor goes and running the engine.

990bw, at what pressure reading does one conclude that the cat is plugged? Or what is the normal pressure for a exhaust system?

I honestly don't know, I have never used one. I just know that is how it's done.

 

http://www.thetoolwarehouse.net/shop/OTC-7215.html