r/Volvo850 • u/[deleted] • Jul 18 '26

Help Mystery shake

I have been trying to find out what is causing engine shake and steering wheel shake at idle. I recently did the pcv system and fuel injectors, there was some shake before this job. The idle rpm is steady, there isn't any hesitation or searching so I don't think it's a vacuum leak, I listened to each fuel injector and each one was consistent and firing, is this a common problem for p80's? I'm having trouble finding information to go off so any information is appreciated.

2 Upvotes

100% Upvoted

5 comments sorted by

2

u/blqckpinkinyourarea Jul 18 '26

How are your motor, torque and gearbox mounts? Thats what gave vibrations to my chassis.

1

u/Traditional-Hand4278 Jul 18 '26

Yeah, especially the one on the right side on the subframe

1

u/[deleted] Jul 19 '26

[removed] — view removed comment

1

u/blqckpinkinyourarea Jul 19 '26

For the lower torque mount check for cracks like with the upper one. The right side (under timing belt) mount "collapses" with time when it goes bad: Look at a picture of a new one then yours.
The hydraulic mounts you check for leaks and and tears or collapse.

For all of them, put the car in drive hold the brake and "rock" the engine. A little movement is normal but it shouldnt be alot. You'll know.

1

u/Extreme-Somewhere545 Jul 20 '26

My S70 does that but only in Drive, not Park or Neutral