Hey Guys. Im an old guy here, used to be active in the 850 section, I had an 850 AWD wagon.

I've recently got a v50 t5 FWD Manual.. Its pretty nice actually.

I have no check engine light.
This thing shakes under acceleration. I changed the perfectly fine OEM plugs yesterday as a last resort, just to be sure -- no change.

I have access to a pro diagnostic scanner, me and a tech at school ran live view, and from what he can see every thing looks pretty good, lambda was perfect, fuel pressure read 400kpa.
A couple codes came out, nothing to be noted, and I dont remember what they were. We cleared them, and they did not come back when we re scanned the car the next day.

I'm going to have my volvo parts guy check see if any recalls have been done to my car (PEM)

i read alot about the FPS (fuel pressure sensor) I was going to go buy one to rule that out, but my car already has the upgraded part number...

I need help!
Thanks!

 

what year and how many miles? I suspect the codes you may have seen were 030x's for random misfires - swapping out the plugs was a good idea but that still leaves the coil packs or their connectors as a usual suspect. Tough to say what you feel as the shaking since that could also be a CV joint acting up (say if it changes with road speed). If you suspects fuel pressure, then you need to consider the FPS, the relay, the fuel filter and the pump itself (or even bad fuel?) or consider other components like the MAF, MAP, hose/vacuum lines. That's where knowing the CEL codes come in handy as most of those parts have signature code(s).

 

I read about the shaking problem when you lower the v50s / s40's.

Seems like the solution is to drop 1000$ on new axles..

 

I had a similar issues on my 06 s60. It ended up needing 2 new axles. u can go rebuilt or used but there is always a risk. I went the oem route $$1,200. My shakes were light at first then got worse and even started happening during braking. Goodluck to you!

 

If it only vibrates at lower speeds, it could be motor mounts.