I drove my 2000 outback to CA and it got a check engine light with a p1507 reading. The engine would cut out briefly at low to medium throttle, not a clutch issue. When I came back to CO 5,600' the light went off and the stalling stopped. Any ideas?

Idle Air Control Valve is the P1507 code. I had the same code on a 95 2.2 engine I just put in a 98 Outback and I marked the position of the control unit on top of the IAC and then pulled it off. Made sure the valve was free and since I had another unit dropped it on. No further faults. Your newer engine is a little different. Might want to try Seafoam first.

Probably the changes in air density.

With the MAP readings constantly changing, the ecu was trying to adjust and set idle accordingly and couldn't.

 

If code reoccurs, I would just clean the IACV. Do a search here for procedure (not hard).

 

O.

i bett the front 02 is on its way out have had 3 bad ones in a row all did not set codes for 02 but had midd throttle problems hesatations and surging and loss of power changed 02 and happy happy.

Thanks for all the help, but what is the 02?

Thanks for all the help, but what is the 02?

O2 refers to the oxygen (O2) sensor.

Not sure if you just have one or two pre-catalytic (front) converter sensors and one or two post-catalytic converter (rear or secondary) sensors.

They provide feedback for emissions efficiency of the catalytic converter(s) by comparing the values pre and post converter.

They look like the butt end of a spark plug sticking into the exhaust system before and after the catalytic converter. There is an electrical connection attached to same.