QuestionQUESTION: I have a 1996 LHS that will not shift out of 1st gear. I checked the trans oil and it seemed overfilled. is there anything i can do to fix it? or should i take it to a shop?
ANSWER: Hi William,
Go to an Autozone part store for a free fault code readout of the engine and transmission controllers. of get it done at an independent garage for under $40. Get the 4-digit fault codes and let me know what they are and we'll go from there. The failure to shift our of 2nd gear (actually) is a self-protective mode that is called limp in. It means there is something wrong that needs attention.
Roland
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QUESTION: got the code p1781 thank you Roland for your help
AnswerIt could well be caused by the trans being 'overfilled', so it would be good to bring the level down to normal as too much fluid can cause this malfunction and fault code. Other than removing a pan on the bottom side of the transmission and draining/refilling, the only other way would be to suction or syphon fluid via the dipstick tube itself. So you could try a syphon approach by inserting a length clear soft tubing into the dipstick tube, and then suck up enough fluid to bring it to the top of the tube (without swallowing any) then rapidly lower the end of the tube to below the height of the dipstick tube and into a container where the syphoning action will collect the fluid that is sucked out. Suck out enough to bring it to the proper level.
If getting the level correct doesn't change the problem, then that 1781 code is saying that there is an issue with a pressure switch in the solenoid pack that monitors the fluid pressure in the overdrive clutch circuit. It could be wire to that switch is open or shorted, or the switch could be faulty, and for the latter a replacement of the solenoid pack (which can be done without opening the transmission) would be the fix.
It could be that the valve body inside the transmission has loose bolts.
It could be that the filter inside the transmission is clogged.
It could be a defective transmission computer
It could even be related to the shifter not being positioned properly in the detent positions.
I can't recommend exactly which approach to take, but once you get the fluid level right, if that isn't the solution, then you could weigh the various costs and tasks, decide which you could do yourself, and try those first. Or go to a highly recommended independent transmission shop and with this background information decide on the best course of action. I don't believe a rebuild is in any way indicated by the code, thankfully.
Roland
