Tranny problem?

Question

I have a '98 volvo S90, 2.9 ltr, with a 4speed automatic transmission. Last week I went to drive it, but it wouldn't shift up from first. First and reverse were the only gears that worked. It was fine one day and not the next, there was no warning, no funky noises or shifting glitches. The next time I drove it, it was fine. It shifted through all the gears normally. Could this have been a computer glitch that fixed itself? What could cause it to not work, and then work just fine? (the fluid level is correct)

it only has 82k miles on it

Answer 1

There is a PNP module on the transmission of such a poor design that its contact get filthy and cause all sorts of problems. Usually though you'll have several lights going crazy in the car if the PNP is malfunctioning. The problem can be intermittent and progressively worsen. Volvo dealers and independent Volvo shops are intimately familiar with this problem on the S90. Having said all that, I agree with the suggestion to have the transmission serviced. Fresh fluid and a clean screen can solve all sorts of difficulties.

Answer 2

Get a transmission filter change... should have been done no later than 60k miles. Chances are it is getting clogged and stopped the flow for a little bit.. then when turned off and pumps released pressure it unclogged.... chances are it will happen again and a tranny fluid/filter change should be over $60 (depends on where u live tho)

Answer 3

suspect a failing speed sensor this is an asian warner unit and the most likely sensor is on the back side of tranny case [ a buried and difficult position] recommend to dealer for this repair.
the park/neutral switch indeed has been problematic on these cars and both faults should have tripped the check engine lamp and the upshift lamp should have been flashing. [if not already on]

Answer 4

most likely a sensor... You should have it scanned at autozone and see what they say.