Vibrating BADLY, and a couple of other questions

[97greenmonster]

Ok, my truck (4.0 SOHC) has that timming chain problem that im going to have fixed next month, but, ive been having a BAD vibrating problem lately. My truck never did that before, and it has gotten worse. At idle it would shake the whole truck from the motor. It was like sitting in one of those massage chairs. I opened the hood and watched the motor, and it was shaking back and forth on its mounts. Is this because of the timming chain, or is it telling me something new? I dont know the last time it had a tune up, but i plan on doing one once i replace the tensioners. Will this help. even tho all of these bad things are happening, i sill managed to squeez about 90 miles for a quarter tank, will all the above getting fixed give me better millage?
Thanks
Clay

 

[explrths]

sounds like motor mounts...???

 

[TerryS1980]

You could try and disconnect the battery for 30 minutes and then let the computer run its course. It might be a faulty sensor somewhere. Is the engine light on?
Yes having the timing correct and a tune up with help with gas milage.

 

[97greenmonster]

No the engine light is not on. Im really nervous to drive this thing. it sounsd like a diesel, and i dont want to throw a rod, and its vibrating badly. So im thinking it really is that tensioner.

 

[95-XLT-VT]

Have a friend help you with this - Open the hood, and watch the engine. Have your friend start the truck, put their foot on the brake, and put it in gear. With their foot solid on the brake have them give it a little gas (until they can feel the truck pull) and you watch and listen to the motor. Then have them put it in reverse and do the same thing. If the mounts are shot the motor will rock over. Good Luck.

 

[explrths]

Have you messed with the plug wires, or checked the plugs?

 

[97greenmonster]

I will try that 95, and no, i have not messed with any plugs or wires, it runs good besides at idle when it warms up.