[Acambo95]

Hello all, New to the forum but long time Mopar lover, Have had my 2011 caliber and 2010 ram for several years. I recently purchased a 2012 Patriot with the automatic CVT, 4 wheel drive and 2.4 motor. After getting it home it Refuses to drive at all, forward or reverse, without severely bucking/jerking/lurching/to the point that it looks like the engine Is shaking off of the mount's, and the front wheels are bouncing up-and-down on the ground.

From other forums I have read on issues such as these, I am torn between it being a CVT issue or the throttle body. However it seems when someone has a throttle body or spark plug issue the vehicle will still run and drive just have a hesitance. My Patriot will not move unless it is from a cold start and on a level surfance and still will just idle and move, any throttle whatsoever will cause it to start bucking.

I have done the basics such as new spark plugs which are oem, And even service the transmission with a new pan filter, canister filter, and fluid. When dropping the Pan I saw no signs of transmission failure such as An unusual amount of metal shavings or burnt fluid, And the spark plugs did not change the condition. I'm hoping someone has had similar issues With the throttle body With the throttle body Being the problem, or how I can ensure that the CVT really isn't need a repair. Trying not to throw money at it And keep the wife happy.

I have a decent scanner which is not picking up any trouble codes.

 

[mr_et2]

Welcome to the group! Is your check engine light on? The best scanner that you can get for a Mopar is a cheap ~$20 ELM327 bluetooth reader and a Mopar specific app, such as either AlfaOBD or OBD JScan (for Android) or AppcarDiag FCA (for Windows). They're pretty much dealer level. Another app you can get is CVTz50. It's Jatco CVT specific and will show you the trans fluid tempo as well as the pressures inside the trans, which are very helpful for troubleshooting.

Since it refuses to drive at all, and it's bucking/jerking that bad, my first suspicion is the CVT. Just because the fluid looked good when you replaced it doesn't really mean much, the PO could have replaced it trying to fix it, and then sold the Pat when it didn't. Neither a throttle body or spark plugs would make it do what you're describing.

 

[todde702]

Is it bucking and shaking in park/neutral or only in drive? That will at least give you an idea if it engine or tranmission. The limp mode it will run in when the throttle controls have in issue does sound horrible and usually tries to run it at 1500 rpm with little to no change in engine speed even when floored. Though it should show the lightning bolt, abs and esp/bas lights.

 

[Acambo95]

Now it has me really stumped. From a cold start it will idle in forward and reverse with a slight jerking, but it moves. If given any throttle the jerking gets more intense and shakes the whole car. I did put it into neutral with it running and back it down my sloped driveway into the street to open up some garage space and found that even in neutral it still bucks rolling backwards. This leads me to believe it's something in the drive train, unless the CVT transmission is still engaged in some way while a neutral? With both front wheels in the air I did not see anything obviously history damaged or out of place.

 

[todde702]

So in park, without the jeep moving, the engine runs smooth and responds to throttle input smoothly as well?

 

[Acambo95]

Forgot to mention that.. Yes, except for one time. When I tried to drive it up the incline for the garage (ended up pushing it up), the jerking was so bad that I put it back in park and tried to rev it up but got nothing. It remained at a steady idle but with the pedal to the floor it did not rev up. Turned off, restarted, and then had throttle again.

 

[todde702]

It sounds like you're going into limp mode. When mine did it, it would idle horribly at like 1500 and hitting the throttle would barely increase the rpm. It sounded horrible and driving it was a nightmare. I had all sorts of lights on the dash for throttle (lightning bolt), abs, esp/bas, traction, etc. I also had about 17 codes stored set. I had two issues, one was the runner control valve went bad and had brought down one of the 5 volt signal circuits. Unplugging that sensor fixed it, but then threw the p2017 code (i think) rihjt after putting a new one in, the throttle body went bad.

 

[Acambo95]

I did another road test, I can get it up to 5-6 mph and pop it into neutral and let it roll, in neutral and rolling it will still buck almost like something is binding up. This is rolling straight in forward and reverse, so I don't think its a cv shift issue. Any cvt or differential experts that could advise something that would cause this? I'm at a loss.

 

[Sandstone]

If the engine doesn't buck, jerk, etc. when in park (not moving) while working the accelerator, then I suggest getting a copy of CVTz50 (requires android device and ELM327 adapter) and checking the transmission pressures against the chart below. The video below is an example of this being done on a Nissan Altima with (basically) the same transmission.

CVTz50 - CVT diagnostics with ELM327

 

[Acambo95]

Well y'all I got the diagnostic reader and according to the freeze frame data my stepper motor was all out of whack. I got a remanned valve body and got it in but have the same problem, so must be something internal. Can anyone help be out with an ACCURATE list of CVT transmissions that are compatible with our Patriots? I know we share with a few other models but I have read conflicting information when it comes to years, engine size and 2wd vs 4wd