Engine Vibration at low Rpm none at high rpm

[Matrixhunter]

car is a 92 TSI FWD

My first guess was that the balance shafts are out of phase but the problem only exists at low rpm below 1000 rpm, maybe it is the balance shafts?. The engine is a Jdm replacement which I just installed a few days ago. The person I bought it off said the timing was just recently done on the engine. Could it be anything else such as a misfire on low rpm? how should I look into the problem, any ideas would help. Also I did compression test today and all 4 cylinders showed 150psi
thanks

 

[Jst4Cyl]

http://vfaq.com/mods/balance-shafts.html

Sounds like the same thing my buddys car was doing....BSE fixed the issue along with

some new motor mounts... I would probably check out the mounts first though...At least this way you are killing to birds with one stone....

Good luck with the fix...

Although they say the BS take away the vibrations from the 3000-4000 rpm, if it was out of phase this could be your issue...

 

[Matrixhunter]

Turns out it was as simple as a fouled plug not firing correctly on low rpm... the reason i didn't look into the plugs was I had the car taken to a mechanic to have it looked over and I had figured he would look at something as simple as a misfire in one cylinder. Mechanics simply are incompetent ... installed new plugs and problem solved. Thanks for the help.

 

[ekanddsm]

Yeah us mechanics dont know nuthing, huck huck huck.
Just kidding, the problem with being a mechanic is you spend someone elses money.
And dont be wrong, because thats a waste of money.
Just trying to make people laugh. Just find one you trust, and it'll work out

 

[black_eclipse]

i have a same issue right now with my 97 2g.. im a newbie also.. if u mean the plug? are you talking about the spark plug wires..??? any help is really appreciated.. thank you!