in my 94 standard explorer sport, sometimes when i try to floor it, regardless of the gear im in, the car shakes back and forth a very slowly accelerates. i then have to release the gas and push down again for it to accelerate normally. just wondering if anyone has ever had a problem like this or might be able to help me.:fcrules:

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"I drink too much. The last time I gave a urine sample it had an olive in it."

Actually, that sounds like it might be a very simple problem....U-joint. When the U-joints wear past the acceptable tolerance, under load (like heavy acceleration) your drive shaft can slip to one side causing an off balance rotation to your axle. This is sometimes all it takes to cause a vehicle to vibrate under load and possibly lose power.

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One big ass 390... One small ass F100... Donuts anyone???

so how exactly do i fix this problem?
any suggestions would help

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"I drink too much. The last time I gave a urine sample it had an olive in it."

Is this a mechanical vibration like something physically shaking the vehicle or is it like the engine is missing and sputtering?

it physically shakes the vehicle, i mean, when i gas it the car jerks forward and back several times till i let off the gas

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"I drink too much. The last time I gave a urine sample it had an olive in it."

Any backfiring or black smoke.


Also, have you ever noticed a slight vibration when you decelerate from highway speed?

A bad U-joint will usually vibrate when you are coasting and then go away whenever you get back on the throttle again.

havent noticed any black smoke, but yes whenever i break on the hgihway my car vibrates terribly. is the u-joint something i can do myself or have to take it a shop?

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"I drink too much. The last time I gave a urine sample it had an olive in it."

They are not that hard to change. It's a good thing to learn how to do and this would make an excellent tech article for this site.

Here is a good article from another site.

http://www.dirtroad.com/articleb.htm

You don't have to worry about that angle thing that they talk about in that article either. It is a jeep site, but the process is the same and everything will look the same too. You will need a 12mm 12 point socket and some penetrating oil to get your shaft off too. The bolts that connect it to the flanges on the tranny and rear diff are usually damned tight too.

do you have an auto tranny? cause i had a crown vic that did the same thing....a lunging and thumping when you accelorate....it did it when it was cold and once it warmed up it was fine. your problem will be the U-joints if its a manual....dont froget to mark the flanges w/ a cold chisel so you can get everything back together the same way...and the flange to driveshaft connection has to be the same too cause it is a balanced assembly so in order for it to not vibrate when you put it back together it needs to be in the same assembled configuration.

my brothers Z71 had to get new U joints and my old F150 had to get new ones at like 75k

i think offroading wear on them.

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1999 F-150 AirRaid, 4.10 gears, tint, superchip, see my gallery for more.

One other possibility: Look for mud caked on the inside of your rims or around your driveshaft.

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One big ass 390... One small ass F100... Donuts anyone???