Very Ruff Idle Need Help

[slvrDsm]

Hey guys.. i have searched the fourms to find out the answer to my shake.. i have a 97 GST and i know alot of people say its either a motor mount or my balance shaft is not aligned.. i tripple checked the timing and its good. i have the prothane motor mounts. all 4 of them. when i installed them i did notice i was able to feel alot more vibration. but not as bad as it is now.. but it is smooth all the way to 7500.. tripple checked all motor mounts an found the rear one split. replace it still the same vibration . i just dont know of anything else an ran out of ideas. ANY help will be greatly appreciated... thanks guys

 

[djalogik]

rough idle may be due to something as simple as a vaccum leak.

 

[nlzn]

rough idle may be due to something as simple as a vaccum leak.

Definitely the first thing I'd check and very easy to do.
Curious, what RPM does it idle at?

 

[xlshotimelx]

rough idle may be due to something as simple as a vaccum leak.

Could the vacuum leak also make the car stall out?

 

[slvrDsm]

it idles at 750 o 850 there are no vacume leaks.. its more a vibration. I checked the balance shaft marks along with the timing marks and every mark is on the dot... I just ran out of ideas... along with checkin the mounts.. all of them are good...

 

[sliver]

Make a simple BLT and start from there. Heavy vibrations on idle maybe just the car trying to catch itself from dying. Even balanceshaft might be a culprit.