86 Caprice Classic Brougham problems

Hello,

This is my first post here. I just picked up my first Caprice. I have a 1986 Caprice Classic Brougham with the 5.0 305 with 105k miles I got for $1250. The car is in very good condition for being 20 years old the only rust that shows is on the lower parts of the doors on the inside.

Anyway on to the problems... The car shakes a little when you have your foot on the brake and put the car in gear (either OD or Reverse). It runs a little rough. When you get going down the road it smoothes out good until you get around 40mph then it acts like it's struggling and doesn't really want to go faster. After you get to about 50mph it acts fine again. My dad and me replaced the spark plugs and changed the air filter and it smoothed it out a little more but it's still a little rough.

Anyone know what to look for? I hope I didn't get a car with a terminal problem...

Thanks for any help!

Ryan

what about the plug wires and the distributor

check the fuel filter too, and dont forget the timing

While you're checking the wires and plugs, look at the distributor cap. My $$ is on a vacuum line somewhere or an EGR valve. Fortunately vacuum leaks are easy to find, pop off the top of the air cleaner, run the engine at idle. Put your hand over the carb and if the idle picks up and smooths out, you have a vacuum leak.

Bob

Thanks for the reply guys. It turns out that the problem was the heat riser went bad and was stuck closed on the right side of the car so it was choking half the engine along with a bad gasket on the exhaust manifold. Gotta love these old cars.

Ryan