'97 850 Turbo Tuning

pappa · Post by **pappa** » 07 Oct 2009, 18:12

I know I'm going to sound stupid and ignorant with this, but I need to know if there is any way to tune down my 850 turbo. I kicks in at the slightest throttle pressure and is just eating up gas at a horrific rate. It apparently is not an engine tuning problem because 2 different Volvo mechanics have checked that out and they say that the engine is in great shape and running at peak.

Is there any way to tune the turbo that allows me to keep it from cutting in at low speeds?

Thanks for any thing that may help!

Post by **MadeInJapan** » 07 Oct 2009, 20:05

You can check the wastegate or at least get it checked- it could be seized or not opening all the way. If it can be worked loose, you can turn it a turn or two in counter-clockwise direction to allow more opening and thus less turbo action at lower throttle.

FCPEURO · Post by **FCPEURO** » 08 Oct 2009, 07:03

Do you know what the boost level is going up to? I have an IPD tune with a MBC set to 16 PSI and I average 21 MPG with mostly city driving. The combined EPA rating for the 850 turbo is 19 MPG so 21 MPG combined is really good.

What is your combined MPG?

pappa · Post by **pappa** » 08 Oct 2009, 12:10

FCPGroton,
Average MPG is 16-17. Don't know what the boost level is. All I can see is every time I press the throttle, the turbo dial jumps to center or beyond and I am not heavy footed. I am as gentle with the throttle as possible trying not to add to this problem.

What is an 'IPD tune', and if it is something to buy, where can I get one?

Thanks!

Post by **matthew1** » 08 Oct 2009, 12:38

It sounds like the wastegate has a few turns in the actuator rod (see another current thread in this forum on that very subject). It's a quick free thing owners do to keep boost in the system.

A car building boost that quickly and to that degree is not normal. Either wastegate or cam timing are suspects.

Are you the second+ owner?

pappa · Post by **pappa** » 08 Oct 2009, 14:05

matthew1,
Yes, I'm the 2nd owner. Had the car for 3 years now and really love it except for this super sensitivity to the turbo and the rotten mileage.
Thanks for the reply!

Post by **matthew1** » 08 Oct 2009, 15:18

Any idea if the 1st owner was at least a little interested in performance?

pappa · Post by **pappa** » 08 Oct 2009, 21:28

matthew1 wrote:Any idea if the 1st owner was at least a little interested in performance?

I haven't the foggiest. Bought it through a newspaper ad.

FCPEURO · Post by **FCPEURO** » 12 Oct 2009, 10:53

I am also thinking that there is an issue with the wastegate. If you floor the car at around 40 mph, does the boost go all the way to the end of the white area on the stock boost gauge or does it stay in the middle?

ChiNorm · Post by **ChiNorm** » 12 Oct 2009, 11:11

This really sounds like the previous owner tweeked up the wasgate, which is pretty simple to undo. Either experiment lengthening it one turn at a time or take it to a mech who knows how to reset it to OEM specs.

This will make a large mileage difference.