mook

ok, i threw this code today in my 01 A4 1.8TQ. i believe that would be the MAF sensor, correct? now, i have a few questions. i have to get emissions tested by the 10th, it will not pass with this code. if i reset the ECU, will it kill the code until the loop testing procedure cycles again, or is the DTC stored until the ECU is VAG'd. other question is, if i do reset the ECU doing the battery disconnect, do i need a code to use the stereo?

NJA4

my guess is the Secondary Air Pump... I've had that guy die on me once before.
*edit* If you pop out your ECU I was told that clears any codes. And yeah, if you disconnect the battery you'll need the radio code to reenable it - should be able to find it w/ the sticker in the trunk.

rickw

and combination valves before I assumed the MAF was bad. Had this the other day on my 2.8, turned out to be a pinched line to the solenoid. Not sure how the '01 1.8 is set up, but probably worth looking into.

mook

where is the 2nd air solenoid?

mook

what sticker in the trunk? the only one i found is on the bottom of the speaker. but i don't think that's the radio code...

CH888

General idea of the secondary air injection system is that it's used during cold starts to quickly heat the cat. converter to improve exhaust quality during a cold start.

Also do a search for secondary air injection pump or combination valve and you'll find tonnes of info. in this forum.

My car stalled on the highway after the pump and combination valve failed. I had my pump replaced along with the combination valve and combination valve vacuum hose.

CH888

...first page of your manual. If not, call your dealer and they'll give it to you.

NJA4

Beneath the carpet in the spare tire well, sometimes it's back there...

rickw

<center><img src="http://pictureposter.audiworld.com/39821/solenoid.jpg"></center><p>there should be two solenoids, one with a green connector and one with a brown connector. The brown one is the secondary air solenoid valve. It should be a small rectangular box (about the size of a box of wooden matches) with an electrical connector and two or three vacuum lines attached.