Jeep Patriot Forums banner

CVT hard upshifts

296 Views 5 Replies 4 Participants Last post by  Sandstone
Working on a friend's 2008 Compass Sport with a CVT. The car has 143K miles on it; the transmission was replaced about 15K miles ago with a used unit, under a warranty that has since expired. Miles on the replacement tranny are unknown.
The replacement tranny worked OK until recently. It now upshifts very hard. Power drops off to zero for half a second while shifting, then slams back in. Basically the exact opposite of continuously variable.
I checked the fluid level with a Dorman 917-327 dipstick, monitoring the fluid temperature with a Launch CRP123 scanner. The fluid level is bang on spec, and the fluid smells fine.

Before I write off this transmission, can anyone recommend a path of diagnosis to see if it just has a bad solenoid or something? The TCM has no codes stored.
1 - 6 of 6 Posts
CVT doesn't shift really, it's a belt and a couple of pulleys. That may be part of it, or maybe it's slipping in which case the replacement unit probably has too many miles on it already.
If you can feel it "shifting" at all, somethings wrong with it. As RossoRacer said, it's just a belt and pulleys, there's no gears to shift. Changing the fluid and both filters might help.
Get yourself an ELM327 bluetooth code reader and install CVTz50 on your phone or tablet. Take the Jeep for a spin and watch the temp and pressures while you're driving.
@relative4, may be a long shot, but I had a bad sticking throttle body that was doing something similar. Felt like a transmission slip / jerk. No CEL and initially no codes. If your scanner supports it, check the throttle body position sensor output vs accelerator pedal output.

On the CVT pressures, there's some info here that might be helpful:
For reference, checking pressures while driving with an Autel scanner.

1 - 6 of 6 Posts