Hello All:

I have a Volvo 850 with a srange problem. The air pump comes on (with the keys off) at random times and remains on for several minutes at a time! It also seems to shut off only after a long time after the engine is turned off!

I am talking about the air pump for the emissions system, not the radiator fan! The problem is getting worse (may be the cold weather?)

Any thoughts on what the problem may be? The haynes manual does not have the schematics to cover the air pump, and no information about it.

Any help appreciated!

Thanks

N. Ramesh

I had the same problem except that the air pump stayed until the battery ran down. The problem was a bad relay. The dealer replaced it under warrany. No problem since then.

had exactly the same problem

it ended up being a bad batch of relays - a service bulletin was raised by volvo to replace. this was after two flat batteries for me.

buy a new relay and replace

The relay for this pump is below the battery area and may be fouled from leaked batt acid causing it to stick on at times.

The relay is grey.

Thanks for the help. I took the battery and shelf out, but cannot find he relay? Do you know where else it might be ?

Thanks

Are you talking about the cylindrical unit located near the throttle linkage? Mine makes a buzzing noise sometimes for about a minute after the car is turned off.