Engine Vibrates/Shakes real bad

The engine on my '94 Explorer shakes real bad while idleing. The vibration from the motor makes the whole car vibrate, even the dash, sterring wheel. Does any one have an idea of what could be causing the motor to vibrate?
Thanks

The engine on my '94 Explorer shakes real bad while idleing. The vibration from the motor makes the whole car vibrate, even the dash, sterring wheel. Does any one have an idea of what could be causing the motor to vibrate?
Thanks

Engines vibrate at idle because they are missing. The most common cause are old spark plugs and vacuum leaks. Check all your vacuum lines carefully, and make sure there are no leaks. Often on older cars the hoses crack or plastic elbows crack. Make sure the tube from the air cleaner to the throttle body is on tight, and has no cracks in it.

Then try a new set of plugs. If you stiil have a miss after that I would try some new plug wires.

Engines vibrate at idle because they are missing. The most common cause are old spark plugs and vacuum leaks. Check all your vacuum lines carefully, and make sure there are no leaks. Often on older cars the hoses crack or plastic elbows crack. Make sure the tube from the air cleaner to the throttle body is on tight, and has no cracks in it.

Then try a new set of plugs. If you stiil have a miss after that I would try some new plug wires.

You know, I have experienced the same problems.. ..after wires, plugs, pcv valve, I found two cylinders with low compression. (10 and 15 lbs) four @ 195.This is at 91k miles. So i'll just ride it out.:( .

You know, I have experienced the same problems.. ..after wires, plugs, pcv valve, I found two cylinders with low compression. (10 and 15 lbs) four @ 195.This is at 91k miles. So i'll just ride it out.:( .
CSL engine restore formula restores lost compression and fixes oil consumption thru worn cylinder walls.. it's a thick oil additive and they're guaranteed to have a difference for any car over 40k miles.. it runs under $10 for the 6-cyl formula.. less for the 4-cyl and more for the 8-cyl..

bought it for my 98 accord with 160,000 miles on it and it did WONDERS making it quieter, smoother, noticably quicker, and (my favorite part) less harsh when idling.. yup, no more rough idles.. so i bought one more for my 97 explorer with 68,000 miles on it.. did wonder too, a lot quieter (4.0L SOHC V6 isn't the quietest thing in the world), smoother pedal efforts, noticed a power increase, and again, smoother and quieter idles.. not as much as it did for the accord, but enough for me to buy get a new can every oil change.. i was so happy with the results i bought another 6-cyl can for my 99 toyota camry.. i noticed NOTHING.. but the car is only 50,000 miles.. i've had enough good experience with it to confidently say that it WORKS.. don't wait it out.. at 91k miles, just buy a can of this stuff.. it does a lot.. i'll give you the website if you want to take a look at it first.. i had 68,000 miles on my explorer, you have 91,000.. i'm sure you'll be very happy with your results.. but note that you'll run through 2 or 3 tanks of gas before you start noticing anything.. hope this helped..

found it.. the site is http://www.restoreusa.com/restorer.html it's a rather pathetic website but it gives you the general info and some before/after test results.. you'll find it at autozone and pretty much any auto store.. its a shiny silver can that looks like a soda can (as you see on their site) and yes, it IS blue haha..

I actually had same problem but this was when the trans wasnt shift into gears. I found out that this terrible shaking which seemed like a out of balance enegine was a ruin torque convetor