Contour Enthusiasts Group Archives Forums General Troubleshooting hesitation 3500-4000. whats wrong?

Alright so i just recently relized that from 3.5k-4k I get this almost surging. I wonder if my secondaries are not opening fast enough. I cant realy feel it in 1st or 2nd gear, but third and forth its real pronounced. and it seems worse at WOT. could it be a vacume leak? my car has 52k miles on it and NO other problems. I replaced the fuel filter like 5k miles ago. Its frustrates me to think my car isnt running 100% So thanks in advance for any feedback or help.

You will know when the secondaries aren't opening up, the car will feel like you are hauling a trunk full of bricks. It will just make noise and accelerate slow. First thing to look at are electrical problems. Make sure all the plugs and wires are good. Combustion chamber pressures are higher in higher gears so the plugs need more voltage to jump the gap. After that you will need to check fuel pressure. I make it a habit to look over the electrical side first before jacking with the fuel system.

i had the same problem a while back. i changed the plugs/wires/fuel filter/and cleaned the upper and lower intake manifold out and the problem went away. not sure which one solved it though. probably the plugs/wires. when's the last time you replaced yours?