intermittent problem

I have a 1985 Mercery Colony Park with a 5.0 engine. 60,000 miles. When in gear at a full stop, the car sometimes will buck foreward a few times and when you take off it does not have much power. If you put the car in park, sometimes this will relieve this problem. The car starts and idle normal. I bought this car from a older man that couldn't drive any more. This car has been sitting for a few months. You could smell the old fuel. I replaced the fuel lines, gas filter, air filter, plug wires, rotor, rotor cap and plugs. I also had the injector line serviced. I took it to a local shop and they cannot find whats causing the problem.

 

Have your timing checked. If it is way off it will cause the symptoms you describe. Also check to see if you have the plug wires in the correct firing order.
Hope this helps,
Billy

 

I agree with the timing, it is however, only one part of the basics that need to be checked.

Ignition system condition as well as fuel system pressure/condition need to be checked. Another possibility is a clogged catalytic converter, emission parts failure or exhaust leaks.