I've got a 93 Volvo 240 hatchback. It's been doing this weird thing where the power seem to cut off completely momentarily and that turns the Check Engine light on. It's just a little blip where the electrical stuff turns off, but sometimes it lasts long enough to make the engine die. This happened yesterday and I made the mistake of popping it into neutral while moving and trying to restart it on the move. It made that horrible sound that happens when you try to start an already running car.

I pulled over, put it in park, started the car, and drove off. Now the engine is shaking. It's worse when I put it in reverse or drive, but still very noticeable in park and neutral.

Any guesses what I did to my poor baby? Can I fix this myself?

 

Auto or manual? Maybe warped the flex plate/ flywheel???

 

how are your motor mounts and tranny mount?

 

"Engine shaking" is an engine with a misfire. You have to diagnose why it's missing. Start with the tune up: plugs, wires, etc. What you did with the restart is a bit of a head scratcher but usually that can damage the flywheel or the starter teeth which will not cause a miss...

 

This would be my first area to look at if shaking is your concern. Unless it's running "rough" and that is causing shaking, which could be even further accentuated if the mounts are shot.

 

How can a "shaking engine" be caused by bad motor mounts? The car shaking can be made worse say if the engine is resting on the chassis due to collapsed mounts, but a bad mount will not make the engine shake!

Besides, the event he describes, what might have caused the roughness, how in the world can that collapse the mounts?
Enlighten me, please!

 

Lev, are you addressing me?

If there is not enough material left on the mounts or if they have completely bottomed out the engine will certainly "shake". Are you trying to say the engine would not experience any additional shaking if you take the motor mounts out? I'd like to see that sometime.

On a former volvo 240 that I had, the tranny mount had completely disintegrated. While the car was being driven the car would "shake". you could say the Transmission was "shaking".

Besides, i don't know to many people that would describe a misfiring engine (as you have theorized) with shaking. They'd simply say the car was not running well, or running rough. But maybe that's just me.

Is there a problem with checking the motor and transmission mounts? would take all of what, 38 seconds???

 

That's just it--there is no such thing as a "shaking engine"! A well running engine won't shake even if it's sitting on a totally uninsulated hard surface which is what a chassis would be with bad/no motor mounts. A "shaking engine" shakes only because a cylinder or more is not firing thus upsetting the balance, that's a misfire. Motor mounts only exist to cushion the vibration of the engine from being transmitted to the chassis and the entire car.

To check motor mounts and transmission mount adequately one has to lift the car, and no, you can't do it in 38 seconds, it would be completely pointless for the problem at hand.

 

Ok. you win. lol.

 

Sure enough, one of the plug wires was completely off. Maybe just a coincidence on the restarting thing. Thanks for your help ya'll!

 

Well, well, what do you know! So it was an engine missfire after all, not a "shaking engine" caused by a motormount????