A week or 2 ago when I started the car (92 Legacy 2.2L) in the morning, it idled rough around 1000 rpm instead of around 1500. The engine light came on, but, I didn't check to see what the codes were. I turned the car off and started it again and everything was fine. For a week or so the car ran beautifully. I drove the car all day today with no problems. Tonight after the car was sitting for 3-4 hours the same problem occured. The car seemed to run okay, there was a little hestitation when driving at a steady speed. I let the car sit for a couple of hours, then went out and started it again. The check engine light was on again and the car was idling rough. I pulled the codes, 35 (canister purge solenoid) and 24 (Air control valve). I have a couple of questions about this. First, what do these things actually do? Does this mean there is a problem with both or can one affect the other (To clarify, for instance if there is a problem with the ACV can this in turn trip the censor for the canister purge solenoid) Lastly, how can I fix my poor car? Any advice or direction to similiar threads would be greatly appreciated. Thanks in advance!

The idle air control valve adjusts the idle and everything.

 

The canister purge valve just deals with emissions, and to be honest, that's what it sounds like the CEL issue is. Mine went a while ago, and the light would stay on...go off....

 

What I'd suggest is clearing the codes...driving the car again, and if/when the CEL comes on again, check the codes and see what's there.

Thanks for your advice. I probably should have added this, a couple of weeks ago similiar problem occured. I pulled the codes, there was a couple of old ones on there I think(12, 15, 35, 24). I reset the ecu and tonight the two codes came up 24 and 35.

hmmm......well the canister purge valve should be independent of the IAC valve.

 

I'd suggest replacing one item at a time. I'd probably do the canister purge valve since it's cheaper then the IAC valve, and they do tend to go bad.

This morning I went out to start the car and it started to idle funny again, the check engine light was on. I turned the car off and opened up the hood and jiggled the hoses and wires on what I think is the canister purge valve. Started the car again, it fired up just fine. Not sure if this was just a coincedence or not. No problems at all today. I'll reset the ECU again and wait for it to happen again.

One quick question, does the canister purge valve have a small hose that goes up to somewhere close to the throttle body? I noticed this hose is not very securely attached, it will just fall off if it is nudged a little bit. Could this be part of the problem?

 

Thanks for your help!

I change every hose on the car every few years. Vac leaks or failure to get a good vac signal can prevent a device from working and the only thing the ECU records is that the device did not work.

yes there is a hose that goes to the throttle body from the canister purge solenoid. Not sure if that would be your only problem, but it might be a contributing factor to it.

I think I will change the small hose, then wait to see what happens.

 

What does the canister purge solenoid cost? The Air control valve?

(I live in Canada if this makes a difference.)

Should I replace these with new, or go to a junkyard?

 

Thanks for your help guys!

The canister purge solenoid is about $75-$85 USD or something like that

 

IAC valve is like $300 USD, so if you do replace that, I'd probably suggest getting it used.