Pontiac Transport Transmission Codes And Slipping

Question:
Okay. I stopped to get gas at the station. My car was running perfectly before then. Started car again and car would not move in drive even though the rpms were high. Placed car in first gear and lightly stepped on gas pedal as car slowly moved. After slowly moving i have to go from first to second and lightly step on the gas. 1998 Pontiac transport mini van 3.4 V6. Warning lights = check engine light. Codes P0187, P0122, P0420 PD Replaced transmission vacuum modulator.

If there is too much pressure on the pedal the rpms will rev up high and the gear will not engage. With light pressure the gear will engage and accelerate as normal. Then i switch from second to third and car will maintain same speed and will increase with light pressure on gas pedal. If i place too much force again rpms will rev high and gear will seem as if it is not engaged.


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Placed car from third into drive and current speed will remain the same and increase with light gas pedal pressure. Once again too much pedal force and it revs at high rpms again and will not stay engaged(or feels like it). Tranny fluid is at normal level requirements! And red in color. Tranny fluid does not smell burned. Reverse works fine with no problems. Replaced PCV VALVE and checked vacuum line hose for cracks or leaks. None found. The next step i am considering is replacing tranny fluid and filter. Then possibly testing tranny solenoids?

Answer:
Well, just sounds like the transmission slipping and needs to come out and get repaired or replaced. Solenoids would not do this except for the pressure control solenoid. Line pressure would need to be checked to determine this.

Hitting the gas harder and it wont move means something internally is slipping. You could remove the pan and change the filter and fluid, but that will most likely not help, other than give you an idea if there is debre in the bottom of the pan.

A failed forward sprag, clutch assembly, sunshell, or other hard part is likely. Debre would be throughout and also in the valve body, which may be some of the cause of your problems.


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