86 Park Ave.

Hello, I purchased an 1986 Park Ave. with 25k car is mint. Just seem to be having a shuttering problem around 45-50 mph. Things I had done. Changed wires, plugs,fuel filter,gas pump,pvc,harmonic balancer,fuel injector flush,I.C.M.,and had tranny power flushed. This car is costing me to much money. Please help to pin point problem. Thanks!

What do u mean by shuttereing? As in engine missfire or just vibration at those speeds? IF it is only at those speeds, If the tires are the originals with 25K on them, then they are shot and have flat spots. This will cause vibration. explain more of the situation.

What do u mean by shuttereing? As in engine missfire or just vibration at those speeds? IF it is only at those speeds, If the tires are the originals with 25K on them, then they are shot and have flat spots. This will cause vibration. explain more of the situation.


Feels like a misfire without a load on it. When in drive goes away when not moving. I can put car in drive and place one foot on brake and other on gas, and i can feel the engine is not running right. Just in Park the engine shacks should run smooth.