legacycentral bbs

So i have a 91 NA legacy and the thing doesnt run very well. I pulled the codes and it threw a MAF code as well as a air control valve code, so i replaced both the MAF and air control valve, but the damn thing still runs like shit. When i start it, it starts just fine, but the idle will bounce from 1000 to about 1500 rpms. When the car gets warmed up once i drop below 2500 rpms it vibrates like crazy, and when i stop the rpms drop almost to the point that the car dies.

Any suggestions?

Did u reset the computer after u fixed those. The computer could still be set at the old readings and still runing like crap. Try reseting it if u haven't. Maybe also the coolant temp sensor isnt working like it should.

What kind of plugs and their gaps?

I'd look for a disconnected vaccum line.

Your symptoms sound like my car when I had the brake booster line off.

How does the engine do when you're driving?

I use bosch spark plugs, and i cant remember what i gapped them at. The engine runs fine while driving as long as i keep it above 2500 rpms

Sounds like the same issue I'm dealing with now(my WTF post is just a few below yours...)We'll have to keep each other updated. LOL'd at the title BTW!

I just read your post. Did you CEL not come on? I would feel rather stupid if its just that damn coolant temp sensor

I'm betting vaccum leak, a hose probably came loose somewhere.

Looked for a vacuum leak earlier today and couldn't find squat. Any ideas on ways to look for 'em aside fom visual and listening for air? The "carb cleaner" method?

soobrdad02 wrote:Looked for a vacuum leak earlier today and couldn't find squat. Any ideas on ways to look for 'em aside fom visual and listening for air? The "carb cleaner" method?

If you find one let me know I'm pretty sure I've had one for a while but it's small and I can't pinpoint it. If it's what's causing your problem though it would definitely be a disconnected hose somewhere and not a hole.

Spent about an hour checking vacuum lines today and didn't find crap. She's still displaying the same symptoms and not showing a CEL. Just to check, I DID replace the CTS with a spare, but to no avail. Ideas anyone?

Have you pulled the codes again after replacing the MAF & IAC valve? If not, pull the codes with the black connectors. Also, I'd suggest doing an active diagnostic with the green connectors to see if anything comes up.

Ive tried clearing my codes, but I keep messing up the process and just get angry. When it gets above 0 degrees here i will give it another try.

You can try just pulling the EGI/TCU fuse, it's fuse 14 in the fuse box near the driver's feet. Leave the fuse out for about an hour.