We own a 1990 DODGE TRUCK DAKOTA 4WD
6 Cylinders 239 X 3.9L FI
Several years ago, it started running rough and dogging out on acceleration. It was like it was only firing a few cylinders. At first it only happened in the winter or when it was cold and rainy. During the summer, the truck ran totally fine. Come cold weather -- we didn't run because it ran so bad.
Then last fall, it started running rough, and dogging out on acceleration all the time. It got to the point, we couldn't drive it because we couldn't safely depend on the accelerator to go when we pushed it -- through lights and stop signs. The vehicle herked and jerked too much for a sane ride.
The power on the vehicle starts to drain when this happens. The lights dim, and it feels like the engine is going to die though it rarely does.
This happens to us at low or high speed. Speed doesn't matter.
It starts up like a champ -- every time. There are no issues with startup.
We're going nuts. We've had it hooked up to diagnostics. It doesn't find anything.
We've replaced the O2 sensor, the ingition coil, spark plugs and wires -- and insulated them with extra corregated pipe, we got a new cat coverter and muffler system as well -- and it is still happening.
My poor husband is going nuts!! Tonight he is thinking of replacing the EGR value, and potentially buying new fuel injectors for the truck!!!
We don't believe it is a vacuum leak because our idle while it does get high -- it goes back down -- which they say won't happen with a vacuum leak.
Last, we realize it could be a leak in the intake manifold, and it could be the coolant sensor.
ANY HELP WOULD BE APPRECIATED. We need this truck desparately. We have upholstered furniture waiting to be picked up. The guy is getting mad at us!!!!
I'd like to be able to help my husband. MANY THANKS!!!!