Idling problems Legacy GT 00

I have a Legacy GT 2000 wagon and the idling goes down to 200rpm when I take the car out of gear and take my foot of the gas pedal. The engine almost shut off then it revs back up to 850rpm. This is a manual transmission. I have given the car a tune up, plugs, cables, filters, coil pack and o2 sensor. I am also getting a misfire on all cylinders. Please help I don't know what else to do. I read that it could be the TPS or Cat, but then again I read that the things I already did might resolve the issue (it hasn't). I don't have the money to replace everything and still have the same problem.

 

Any help will be appreciated. Thanks.

You may want to take your car to an auto parts store that offers free code checks. There may be a stored code that could point you in the right direction. Looks like you have hit all the usual suspects.....maybe you have insufficient vacuum?? Not sure if its possible to have a partially busted timing belt that slipped a tooth or two.

It might be worth cleaning the IACV (idle air control valve) located on the throttle body. Do a search for IACV cleaning on Subies, its pretty easy with Q-tips and some gas to get things really clean. You will need a replacement gasket for it before you remove the unit, your Subie dealer can get the gasket. If you do clean it, be sure to clean the interior of the unit itself while rotating the internal cylindrical piece so that you can reach both sides, and don't forget to clean the interior of the coolant hose attachment point.

When you look at the internal parts, you will know exactly what I am talking about.

 

I've cleaned the IACV on my 00 Outback twice now in 191k+ miles.

check the pcv vlave, and check the EGR valve to make sure the port from the exhaust to the intake isn't stuck open.

Thank you for the reply. I borrowed an ODBII tester and it says there is a misfire on all 4 cylinders (i forget the code). I will try to clean the IACV and see if that works. Is there a way to test the EGRV instead of replacing it? and the pcv valve was replaced when i did the tune up. I am not loosing any horsepower when the car is in gear would that rule out the vacuum or pressure? Thanks again for the advice I hope it will repair the problem I need to get it inspected.

sure you could just replace the egr valve, however it will not be the cause of a poor idle unless it is stuck open. It may not hurt for u to buy a repair manual, like a Chilton's or Haynes, available at your local auto parts supply store. with the symptoms you are having, you would just need to remove the valve and physically look at to tell if it is stuck open. another indication of this would be low vaccum at idle. but an intake leak could give you the same problems and symptoms. check the amount of manifold vaccum at idle. it should be between 17-22"Hg

any luck?