We are having serious issues with our 2001 Town and Country 3.8L.

Existing problem:
Error code 300 (random misfires). Annoying ride, with audible pops from the plugs, stutter, and hesitation.

What I've done:
Plugs/wires/coil initially changed out. Code still came up...then I switched out the injectors (two actually), since the misfires are occuring on #3 and #5.

After a compression test showing all were at 170-175 psi...
One dealership told me it was two valve springs, and they would fix for $600..."hoping" that would fix it...saying the compressionesentially meant nothing.Another dealership said it was a burnt valve that could be fixed for $1200, and that it was the "first step" to fixing it. I'm a cynic who doesn't trust either of them.

Pep Boys did the compression test, and said they are 95% sure it is NOT internal. The springs and burnt valve diagnosis made no sense to them.

Next thing to check?
I thought the MAP sensor or Throttle Control, but from what I understand, and cylinders would misfire if that was the case...not just 3 and 5. The main CPU control bad? Would I see any other symptoms for that? Is it possible? If not, does anyone have ANY idea of a possible problem? This is really driving me nuts.

Thanks
Bryan

 

would think there would be more codes if the cpu was bad. Are the spark plug wires routed right? I would think that there is either a leak in the intake or in the exhaust or that the timing is off.

 

the car is probably misfiring