Took our 2008 T&C with 105,000 miles to Aamco for a full service just to keep up with maintenance. Less than 300 miles later started having trans issues.
Will run great but seems to be triggered by long idle times or stop and go traffic. Trans will not shift up out of 2nd (or possibly 3rd) gear. engine will just rev up and up. Tried shifting into manual shift mode but there was no option on the dash and sliding the shifter sideways didn't engage manual mode. As soon as I stop the van, turn it off, and turn it back on again, the van runs GREAT. Sometimes for only 10 miles or so before I have to do it again but sometimes it will go days.
Like I said, seems to be triggered during long idle times or stop and go traffic. I took it to a trans shop (not aamco) and he said I have low pressure inside the trans and it needs rebuilt/replaced.
I'm blown away that I can just restart the motor and it runs perfect so I am not willing to accept that diagnosis yet. Lol. I was a yamaha outboard tech for 6 years and I'm very mechanically inclined, but I am not experienced with transmissions.
Trans fluid is at the perfect level. Originally I was getting P1404, P0733, P0734, and P0792. I replaced the output shaft sensor as a cheap shot in the dark but no resluts. Now Im getting recurring codes P1404, C342D, P0733, with my harbor freight scanner. P0734 and P0792 are not recurring.
I have spent hours researching but I am not sure the next best route and I'm hoping to avoid a new trans if possible. Im considering changing the PCM, and then possibly solenoid pack if that doesnt work.
Any insights, information, or comments would be greatly appreciated. My growing family loves this van and would love to forego the expense of a trans overhaul. I thank you all for any knowledge you're willing to share.