This has been on-going since I got this 940 n/a last March. After many dollars and DIY hours, it's a lot better — but better "hidden" would be more accurate, according to my experience (and my expections for a car that I thought would be a step-up from the 240 series).

Symptoms:

> Not Driveline related (can be produced in Neutral)
> Originally obvious at idle (better now, but...)
> Became very obvious when put in gear (holding brake, as at a stop light)
> Increases with RPM. Very annoying at shift points (2500 - 3000 RPM)
> Can be felt in gas pedal (and steering wheel) at normal road speeds. (very "buzzy")

Parts Replaced:

> Tranny-to-Exhaust bracket (home-brew but does the same job at the same place)
> Driveshaft Center Bearing and Mount (Volvo OE) 130k preventive maintenance
> Motor Mounts ("German OEM") Raised engine up off X-member, but little improvement
> Tranny Mount ("Made In Germany") This and MMs "subdued" the vibration effect only slightly
> Harmonic Balancer (Volvo OE) Smoother — sort of "clipped the peaks", but still feel vibration at same RPMs
> Replaced Motor and Tranny mounts (after 4 months) with Volvo OE (HUGE improvement!)

Compression is even across all 4 cylinders, and all plugs look the same. Haven't checked valve clearances yet.

If the engine had been as smooth back in March (when I got this car) as it is now, I might not have noticed the vibration — not right away at least. But having lived through this, I can tell it is still present, even though it has been extremely "muffled" by the OE mounts.

Is it something inherent to this version of the B230? (Or this particular B230?) In 40 years of 4-cylinder Volvos (including 10+ years in an '86 240), it's new (and concerning) to me. Others have had the same symptoms too, according to my BrickBoard "Search" efforts. Tim Kline, with a 740 a couple of years ago, wrote posts that sounded just like mine. But I never saw any resolution. So unless something comes from this post, I'll live with it and hope it gets no worse.

P.S. Anybody interested in some hardly used, cut-rate "look-alike" mounts real cheap?
--
Bruce Young,
'93 940-NA (current)
'80 GLE V8 (Now gone)
'83 Turbo 245
'73 142 (98K)
'71 144 (track modified--and still here)
New 144 from '67 to '78
Used '62 122 from '63 to '67