violent shake and very poor fuel efficiency

[illusionaryline]

hello, i have been having problems with my car, i am getting about 18L to 100km compared with the normal 10L and ocasionally when i pull up at the lights the car shakes violently also gear changes are rough, does any body have suggestions before i head to the dealer?
thanks in advance

[1SIKBNZ]

uh o... sounds like tranny issues... =(

[trymonlam]

let's hope it's not. bring it to a mechanic to have it check out. if it indeed is the tranny, don't opt out for getting a new one just yet. look for a tranny specialist in your area for them to take a look. a member here once had a small part in his tranny replaced and saved it with only a few hundred $.

[jnenad16]

if your car is newer than 97(if it runs by ME 2.x/3.x), Id say possibly MAS.

nenad

[illusionaryline]

yeh its a 98, thanks im hoping its nothing too major n thanks for the advice ill head to the dealer tomorrow

[Capt]

Hope all goes well. Let us know what the outcome is. I am having a very similar problem (actually identical).

EDIT: Any word yet?

[slowpoke]

bro,

had the same problem a few weeks back... on the rough gear changes, the problem on my car was the uinversal joint coupling.

for the violent shaking, you can do the following:

1. check your throttle potentiometer (its an assembly located right after the tube coming from the air cleaner and right before the manifold.)

This part contains the valve that controls the air/fuel mix. On one side there's a plastic cover that's held on by five or six torx screws. Open this up and check that the wires still have their insulation... if the insulation has melted off, you can try and repair it by replacing the wires. It cost me about $250 equivalent to buy a surplus part. Will try to repair the broken one and resell it.

2. Check your fuel pump, see that its working right

3. Clean out your gas tank

Hope it helps... BTW, my ride is a totally stock '94 W202.

[illusionaryline]

hey guys thanks for your advice i took it to the dealer, they replaced the MAS, im waiting til ive used the tank in it to see if fuel efficiency is better

[kameraguy]

Did the new MAS correct the vibration/shaking at idle? How about the gear changes? Hopefully you felt a difference shortly after the repair.

Just curious as I think I have a similar issue...although not as bad as what you have described. I don't have a CEL, but I heard a failing MAS doesn't necessarily trigger it. Thanks!

[illusionaryline]

yeh i didnt have a CEL either, yeh the MAS fixed the shaking at idle and gear changes seem to be alot smoother, however it feels sluggish at times- when i overtake i have to mash it into the floor when i never used to. :S