When my engine warms up the car shakes, sometimes quite violently, especially when lights are on, radio and i'm indicating etc, but only when idling. everything okay when driving. however today after work, when i turned the engine on, it immediately started to vibrate and the odometer and handbrake light started to fade in and out with the vibrating. Also the battery light would come on and off through out the journey. it all stopped when i had the car over 1500rpm, starting again when i slowed or stopped. ihad everything i could turned off but it didn't make any difference? help?

Car feels like it's surging, engine shakes violently in idle ...

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May 10, 2012 - 13 posts - ‎6 authors I'm wondering if the lower engine mount is shot. Last time I saw the engine shakingaround like this was before I replaced the upper engine ...

That usually has nothing to do with the things you replaced haha maybe the wheel clutch but if you replaced it, it would ne fine. With the older model of these cars i would suggest its the block, especially if you have over heated it a lot. Possibly even the transmission. If your transmission is slipping it can cause the engine to shake pretty badly

ckeck your c.v. axles

run the fault codes
could be bad injectors , crank position sensor or cam position sensor problems

Check the throttle position sensor, or the idle air control valve

there are a LOT of problems that could have this effect on an engine ... but from this description it sounds like your timing chain might have skipped a tooth. If your timing is off, the pistons will not fire at the correct time, and will cause a violent shake in the engine, and the engine will lose almost all power. This issue would also cause a hard start whenever you try to get your car started, so it may not be this ...
You might have a leak in your head gasket which is leaking either water or antifreeze into one of your pistons. When you start the car, is there a sweet smell in the exhaust? If antifreeze gets into a piston, it usually stops that piston from firing at all. This could cause a violent shake in the engine, and might not cause a hard start, so it would only be noticed when you start driving.
You could have a dead spot in your distributor cap -- the piece of the engine that distributes electrical charge to the spark plugs. Replacing the plugs is a first step to finding out if it is this problem -- it is cheaper and easier to do than replacing / repairing the distributor cap. When the plugs don't want to fire correctly, it has the same effect on the engine as antifreeze in your engine -- a violent shake and diminished power.
There is a SMALL possibility that it could be your transmission. If your transmission is getting stuck in the wrong gear, or between gears, the engine will try to pour out power, but will get so bogged down by the malfunctioning transmission that the whole car will shake. This is a VERY rare problem, but it does occasionally happen.
Your car's computer might not be sending or receiving the correct information to or from the engine. If this is the case, it could be pumping a different amount of fuel to each cylinder, causing the engine to fire too hard sometimes, and too soft other times. This would prevent you from getting proper acceleration, and could cause a shake in the car, but I don't think it would be a Violent shake like you described.
You could have a bent Cam, which would not allow the valves to function correctly (but this would probably keep the car from starting). It could be a bad bearing in the engine (but this would probably keep the car from starting at all). You could have faulty valves (but once again, it would probably not start at all). There are a lot of other possibilities as well ... but I think you get the point here. It is going to take a while to figure out exactly what is wrong. If you have a friend who is willing to help you out, or a really cheap mechanic that you can take it to, you'll probably save a lot of money over taking it to a corporate shop. Best of luck!

check the drive shaft joints for worn/siezing

change out your distributor cap sometimes if its not pushing the right amount of current to your spark plugs it will cause a misfire it wont throw a code but will make your car vibrate violently. also check your compression and timing

I Would Look Into ECM Probled As It Takes over when the Engine reaches 195-220 Deg the ECM Takes Charge of Timing ETC.

You could check to make sure the plug wires are all intact. If they are, try replacing the wires and plugs. It could also be that the idling is set too low. It could be the mapping sensor as well. Also try, Maybe the coil pack is going bad. It will cause the engine to misfire. The can be bought at Auto Zone or Advanced Auto. Some place like that...