I've decided to take the air pump off to inspect for water and whatever might be causing it to be inop ( as reported by Volvo service. ) The question is when does it come on, and how do I know if it is actually working. I purchased the UK Haynes manual but no reference to an air pump at all. Any help would be appreciated

Tony L.

Tony,

The air pump on my 98 V70AWD went at about 76000Km... just before the end of the warrantee. It was found to be defective and the whirring sound is what gave it away. I was told that it shouldn't be making the whirring sound. I was also told the sound was an indication that it was on its way out. Good luck, happy motoring,

ERIK

Thanks guys ... Rich I believe you mentioned that the new V70 has no air pump, which brings me to the question, what is it for on the 98 ? emissions ?

Tony L.

1998 Volvo was still using the air pump in combination with the SAS valve to direct air into the exhaust at cold start ups. 1999 on the air pump went away, Volvo has a different scheme to get the car into emmissions specs now.

After you have it all out take two leads and run it off the battery, if it's shot then it won't work.

You'll know when it comes on when you hear it. It usually kicks in about 10 to 30 seconds after you cold start the car. You'll hear a higher pitch whirring almost like a blower motor gone bad or a small jet firing up its engine. (kinda cool sound actually) The other way to know its on is to get yourself an OBDII scanner. The scanner should be able to pick up on the signal and tell you when the circuit kicks in