CRD Mimi wrote:
We have a 2006 Liberty CRD LTD. Love it so far ... except when recently returning from a trip. On the HWY, about 65-70 mph, all of a sudden the car takes on a life of its own - goes full throttle, won't respond to braking ... my husband was driving (thankfully) and he put it into neutral (it revved way up), got over into the right lane, shut the engine down and safely pulled us off the road. He started it up again, it gave the light for brakes being applied while accelrated is also depressed (duh). Turned it off again, sat there for a few minutes, turned it back on and it was fine. Drove the rest of the way home (~350 miles) with no repeat. Took it into the dealer on Monday morning , they still have it and can't figure anything out. I saw on this site where a couple of others reported this same problem and it was the throttle control motor - reported this to the tech, but he says that all checks out OK.
It also does this weird downshift whenever I am going 55-60mph and on even a slight incline - it will downshift, then quickly shift back up.
One more thing - it only has 6000K miles and has already used 1 1/2 qts. of oil.
Any ideas out there? Thanks ... this is not our first Jeep, but it is our first diesel.
1. Stuck throttle: No clue, the mat sounds like a good explanation. Others exist, but are not very likely.
2. Downshift--- see transmission problems threads on this site. This vehicle tends to do this. The programming is designed to engage the Torque Converter Lockout at 55-60, sometimes it gets confused. If you are lucky-- it is only a minor thing and only happens once in a while, with a shift down and then back up. If that is the case, it is just an annoyance. If it starts hunting for gears and wont stay put-- then you are one of the unlucky ones with tranny problems. Mine is unlucky. It will shift up and down constantly and sometimes violently under the following conditions: You apply throttle to accelerate to highway speeds and then lessen the throttle abruptly to maintain speed, with the RPM ending up around 1500-1800 when throttle is reduced. This is probably a combination of bad software and a poorly designed tranny pump. Could also be low tranny fluid level (not in my case, I checked it and made the dealer check it as well

).
3. Oil Usage-- This is normal during break in on a diesel. Keep an eye on it. Consider doing the EHM or the Provent to prevent this oil from ending up in your turbo air intake. Some diesels use more oil than others. Mine is currently using 3/4 quart every 6000 miles. Check your oil first thing in the morning after it has set and is cold. This engine takes forever for the oil to get back to the sump and if you are checking the oil at the fill-up station you may be thinking it has less oil than it actually has. After you change the oil, making sure to put 6.3-6.4 quarts in it, let it sit for a while and then check to see where it is at on the dip stick. Mine is right in the middle of the full and min mark. Some CRD's are apparently different-- with some folks notching out new min and max lines on their dip sticks. If you have someone else change the oil-- make sure they put 6.4 quarts in-- not 7-- or worse 12+. It is not a cummins and some dealers have overfilled this thing.