1994 Chevy Cavalier--Vibration at Idle?

Question

I have had a nasty engine vibration at idle in my 1994 Cavalier with the 4 cylinder/automatic trans that I can't seem to get my arms around. Raising the idle slightly by resting my foot on the accelerator eliminates the vibration, but I don't believe that the idle is adjustable on that car.

I have replaced the front side engine mount that was broken. I've changed the plugs and wires (distributorless ignition) and the ignition coil with no effect. Oddly, when the front struts were changed (unrelated--leaking) the vibration diminished for a few weeks.

I haven't crawled under the car to see if the lower engine mount is trashed; I understand its not as easy to replace as the front mount was.

Has anyone had experience with this condition? Any ideas? The engine otherwise runs great and the fuel economy is 25 city 32 highway so I don't think its an internal engine/fuel/ignition problem.

Any help would be appreciated

Answer 1

I have had the same vibration in this motor. What can happen is the right lower motor mount collapses. This hard to determine as it will not look broken or anything else, but the rubber inside it was not hard enough and it sags and acts like the motor is grounded out. This mount is on the right or passenger side at the back of the motor and you can feel it from above, but can't see it very well. I used to see if I could stick my finger in the lower part of the mount and if I couldn't I was pretty sure it had collapsed. Replacement is easy as only four nuts/bolts and no need to support anything. Good luck.

Answer 2

1994 Chevy Cavalier

Answer 3

Since your car is a four cylinder it will be harder to get it to go like a six cylinder with very cheep mods but if your willing to try then this is what I recommend. I did all of these mods to my 1992 Chevy Lumina coupe it has a 3.1L V6 (sorry) and what I did to my car made a pritty noticable difference in performance.The first thing that you could try is a tune up this will give your car some more power if it has not had a tune up in a wile. I would change the o2 sensor change the spark plugs and wires clean out the PCV valve change the air filter Fram air hogs are good because they let more air into the engine and they can be cleaned and unlike K&N air filters you don't have to oil them.I also moded the air box by drilling six half inch holes into the baffle inside the air box which did make a little differnece.The computer needs to relearn its peramiters before you start to actually feel anything this takes about 10 to 20 miles. However if you do dicide to mod your air box than you should not mess with the intake hose that runs behind your head light becasue this can have negative efects on performance. Next try to clean out the intake manifold and throttle body I did this on my car and it made a world of difference you would not beleave the crap that came out of the throttle body I had to use two cans to get everything out of the engine. I also put on a cheap high flow after market muffler that is a little louder than the old one but it did make a difference. I also put on a high flow catalytic converter wich helped out even more. And to help out with handling I put on 16 rims off of a 1993 pontiac grand Prix this made a BIG difference in handling I went from crappy 14x6 to 16x8's and I also put on front and rear struts that are for a Euro Lumina wich lowered the car about two inches it makes it look a lot better and now it handles like its on rails.

Answer 4

1994 Cavalier

Answer 5

if that car has the 2.2 in it ,i have had the same problem your having,i changed all the mounts and it seemed to help it ,but it never did go away,we ran a compression check and everything on it,after driving it for a while with all new mounts on it,one day it just went away,,2 weeks later though it came back,i changed the harmonic balancer in it,and never has it done it again,i don't know if that was the problem to start with,it too ran real good,and the mileage was good on it also,if its got a lot of miles on it ,the chain and gears for the timing will cause it to vibrate a lot,other wise it will run good,i have one right now that ran good up until it broke the chain on it,we have to pull the engine to completely clean the pan out on it,at the owners request though, were also going to check it for metal fragments,look at the back mount,it is harder to change,but that could be it,good luck on it.

Answer 6

I had similar problem on my Honda. I was told that front mount can be changed easily as they are solid piece. Rare are hyadraulic, therefore cost more and takes more time. Moreover when this problem happened, my engine was touching the fan which more turbulance. Changing front mounts took care of problem for only 6 months.

Answer 7

The lower mounts is probably bad - since the top was I would say that it also is bad.

And also the transmission mounts also.

Might as well get them all done while your down there,

Answer 8

Ggriffin1972 appears to have the right direction motor mount
replacements - if you had to change the from just like ball joints we should be consistent to balance things.. i will go with Ggriffin too ... sometimes its just the process of elimination