When traveling at low speeds 40-50, when it shifts into overdrive, if any load is put on the engine, it misses. That is, until it shifts out of overdrive. It almost feels that the engine just doesn't have enough of power to pull at that high gear. It runs great otherwise, no other miss at all. '96 3800 series 2. Any one else have this problem.

Normally as the motor is loaded during an overdrive shift, ignition can fail. The resistance across the plug goes up and anything from a plug to Ignition module can be misfiring.

There are many other possibilities dealing with sensors sending wrong information and knock sensors retarding timing too far etc.

Check Fuel Pressure during this condition. Fuel filter replacement etc. It may be leaning out.

Luckily you have an OBDII and it can tell a good code reader performance in real time.

Good Luck

EDIT... some have also experienced clogged Cat converters.. to cause low power during high power demands... Just a mention.

Edited by: bassasasin

Thanks, I'll start with the fuel filter, and go from there.

you could check the park plugs if they are craked on the porcelaine,it is noticable by seeing black stripes on the white part of the plugs,if so bad plugs wire is the cause.


good luck and keep posted