I am having the following problem on my 01 V70 T5 with a manual shift trans. When I change gears and apply FULL throttle, the car will "lug" down and hesitate right before the turbo kicks in. It is NOT normal turbo lag, it actually loses quite a bit of power and the revs begin to vary up and down. It only does it at completely full throttle, meaning you can feather the gas and clutch and still make the car scream, but if you just shift and pour it to it, it will lug down pretty bad before the turbo spools up. Once the turbo does spool, however, it will take right off. I am not getting any error codes, by the way. One idea I have gotten from some general research is the "Boost Control Solenoid" (BCS) attached to the air box (also called the "Boost Pressure Valve", I think.) If anyone has had similar experience, I could really use some help! Any input is greatly appreciated! BTW, I am new to the forum and to Volvo and love them both so far!

 

This is just a WILD guess, but if it only does it at full throttle, maybe there is something wrong with the potentiometer. Seeing as these car's use a "wireless" throttle, it has to have some sort of a potentiometer that tells the ECU how big to open the butterfly. It might be that the pot gives a bad/funny reading at it's full open position. I suppose it could also be the ETM.

 

Can you tell me location of and how to troubleshoot the potentiometer? Also, what is an ETM? Thanks!

 

The position sensor (potentiometer) is located on the accelerator pedal assembly. I haven't had a look myself so can't help you more than that and the Haynes manual isn't very helpful on the subject.

ETM stand for Electronic Throttle Module. That is the butterfly goody that opens and closes the opening into the intake manifold. It is located underneath the intake manifold. The easiest way to get to it is to take the manifold off, just make sure you replace the gasket when putting it back on (oh, and it's not quite as easy as I make it sound )

I'm sure if you can get Tech's attention he would be able to give you some more detailed info.