my car must just not like me. on start up there is a high pitch whine comin from the passenger side in the engine bay and the car idles rough until after about a min. then the whine dies down and the car idles normally. and it only does it when the car sits for like 4 hours or more. could it be a problem with oil pressure getting to the turbo until enough builds up or it the turbo just shot?


2000 A4 1.8T

 

It's the secondary air pump. If it sounds like a vacuum cleaner, it's basically shot. If you have emissions testing in your area, you have to replace it or you'll throw codes that will fail you. If you're not required to pass emissions regulations, you can delete it. I forget who sells the delete kit, but I know CincyTT knows (he's posted it before). Send him a PM and he can tell you.

 

oh ight. thank alot..that sounds alot better than a shot turbo or oil pressure. is that hard to install?

 

I haven't had to change one, but make sure it's the problem before you swap it out - it's expensive (around $300 from www.purems.com). Chances are, that's it. I'd stop at AutoZone and have them scan your car for codes - even without a check-engine light, you may have a code or two that will point toward it (or at something else). The symptoms sound like the SAP though.

 

i seem to have the same problem with mine too. it does that sound on start up after it cools down for a while

 

I dont have a filter on my little hose becuase i took out the box. However mine sounds loud and im not throwing a code just p0160 or what ever it is Bank 2 sensor 2 dead.

 

SAP usually runs on cold start for 30 seconds or so (varies depending on coolant temp). When it shuts off, your idle drops from cold start speed of 1200RPM or so, down to the normal idle of 700ish (maybe a little higher, again depending on engine temperature).

 

I ran without the breather filter on the SAP hose for awhile, but it's good sense to put it on there. It's around $8-9 at the parts store, and may keep crap from getting into your SAP and possibly ruining it. As for your code, I assume you know that bank 2 sensor 2 is the post-cat sensor on that side of the car, used for catalytic converter efficiency monitoring.

 

Also check your Power Steering fluid level...and top up with the proper Pentosin fluid if low.

 

I WAS THROWING A P1128 but that was before it started whining ill have to scan it again to see if there is any new codes