rough idle, new to subaru, codes 22 and 35

heathcom · Post by **heathcom** » Fri Oct 12, 2007 2:34 am

Great site ; ) Learned alot in just a few reads. Just bought a 91 AWD Legacy, plain one, nothing fancy, for 250.00. Good deal eh? Mechanic said all it need to pass inspection was new brakes and rotors which I did this weekend. (however, a snapped bolt in the caliper took an entire Sunday to tap out grrr). Anyways, it has had a rough idle especially at warm up, chugs a bit here and there after it warms up. Check engine light is always on. Nothing major but would like it to stay running good especially through winter. I looked at some pics that were posted so atleast I know where the canister sensor thing and the knock sensor is located. Question is, and Im a guy that loves to save a dime but spend hours of time, can I replace the sensor or sensors with a resistor? and if so, what level of resistance and maybe a quick how to.
I'll look at the junk yards but hate to get the same issue with a replacement part.
Thanks in advance if you can help.

ericem · Post by **ericem** » Fri Oct 12, 2007 3:15 am

The knock sensor is right under the throttle body/intake its a plastic piece with a bolt through the middle on the driver side. I wonder if the TPS(throttle posistion sensor) might be the issue. Is it idling very rough and at a low rpm? If you adjust the TPS it makes it idle higher but you also need to do it a special way. I did it yesterday made the carb run loads better. If you want to do a good tune up change the spark plugs, wires, fuel filter, air filter, clean the Mass air flow sensor with contact cleaner, and seafoam via the gas tank. Seafoam works wonders lol.

heathcom · Post by **heathcom** » Fri Oct 12, 2007 3:37 am

It idles fine, just when I tap the gas it putters and jerks for a bit til the rpm gets higher. If I step on it, it will chug and putter for a bit but normal 30 - 40mph on a straight road is fine. I plan on giving it a nice cleaning and tune up this weekend. Since it seems the two sensors arent "repairable", I'd like to bypass them somehow if possible.

ericem · Post by **ericem** » Sat Oct 13, 2007 12:41 am

I know on the USMB forum some people used a resistor for the Knock sensor. This thread here will help you out if you want to go the resistor route.

http://www.ultimatesubaru.org/forum/sho ... r+resistor

Maybe you have a ground issue? The canister purge solenoid could probably be found for pretty cheap on this forum used from a parted car. Could not find a new one.

Here are your codes.

22 Knock sensor Abnormal voltage produced in knock sensor monitor circuit Sets in regular fuel map and retards ignition timing X

35 Canister purge solenoid valve Solenoid valve inoperative

ericem · Post by **ericem** » Sat Oct 13, 2007 12:43 am

Here is a good diagram of the fuel system and where the purge solenoid is.

heathcom · Post by **heathcom** » Sat Oct 13, 2007 3:19 am

Thanks for the diagram, pictures always make it easier. That link for the resistor thing on the other hand, alot of greek and terms I have no idea what they mean

I'll begin with a good tuneup, plugs, wires etc... than reset the codes and go from there. I'll post what comes of it

Thanks again for all the info

heathcom · Post by **heathcom** » Mon Oct 15, 2007 1:05 pm

I put in new spark plugs, wires, oil filter and a canister sensor from the junk yard. There was almost double the amount of oil that was supposed to be in there

. im guessing that was the cause of the chugging since it runs like a champ now. However still getting codes 22 and 35 but if it runs good I'll leave it alone.

Thanks for all the help and this was the first car in years that I actually enjoyed working on.

legacycentral bbs

A forum for 89-94 BC-BF(BJ) Legacy Owners and Fans

rough idle, new to subaru, codes 22 and 35

rough idle, new to subaru, codes 22 and 35