Alright, I will try to make this short. Have a weird issue going that has more than 1 symptom. It would seem the immediate logical answer is pointing to transmission, but here me out here.

2006 Dodge Durango, 130k, 4.7 non-Hemi.

When I first bought it used, I noticed surging in idle and sometimes the transmission would downshift when going up a hill. Additionally, sometimes it would not fully downshift into 1st after a stop until I pressed the accelerator again. In other words, when I pressed on gas, it would downshift slightly roughly then take off and be fine. Took it to a trusted garage, they couldn't find anything at all on any diagnostics and on a hunch I suggested they change the TPS, which they did and it fixed all the problems. That was about 10k miles ago.

Today I was driving slowly in a parking lot and the check engine light came on (which btw, it didnt do in the prior instance just described). I noticed no other symptoms whatsoever so was thinking a sensor of some sort.

Drove about 15 miles at 60 mph with no issues at all. Then suddenly, when going up a hill, it dropped down into 3rd I think and I had to drive about 40 the rest of the way home bc it would not shift out of 3rd.

Got to autoparts store, they ran diagnostics, found a code that suggested the MAP sensor was bad. After I got out of the store and tried to restart, it would not. It was cranking but not turning over (and the weird thing is that it would continue to crank for a couple seconds even after I let off the key, which was weird).

Got a ride, went home to get my tools and came back, changed the MAP sensor and it started right up. Upon starting it was idling initially at about 2000 RPM, then after about 1-2 minutes it dropped back down to 500, which is normal idle. It only used to do this when the TPS was bad before.

Upon driving home, I noticed that now the transmission is in limp mode, not getting out of 2nd. Weird thing is that if I am in Drive and try to go up a hill I cannot go any faster than 25, even if I press the gas more, it just revs but feels like it is out of gear completely, though once I slow down I can feel it pulling again.

I just wonder if this could be the TPS again? I find it very strange that all of this happened at one time to be the transmission itself. Any thoughts?

Mike

 

Hi Mike:
Has the trans ever been serviced? I guess it could be that the new TPS has crapped out, but not many folks have reported issues with a 2nd TPS going bad.

The symptoms you describe could also be caused by a failing torque convertor or possibly a failing fuel pump that won't supply enough fuel for the higher rpms.

Before we tie any big bucks in this, how old is your battery? A dying or flaky battery can cause all kinds of trans/engine issues in our Durangos.
Also do a battery disconnect reset by removing the negativwe terminal from the batery and then depress the brake pedak for 30-60 seconds.
Then reconnect and take it for a spin to see if the trans is shifting any better.
I would have the battery load tested to rule out any erratic operation issues due to bad voltage regulation.

Don

 

Hey, thanks for the response. I was a little bit skeptical that it could be another failing TPS within less than a year as well. Moreover, even if it was, I would be led to believe that this might be pointing to something else causing the failures if it was indeed the TPS.

Well, I got in it this morning to drive to the auto parts store to see if there were any codes (even though the check engine light had not come on). When trying to start it, it did the weird thing where it continued cranking after I let off the key. Got it started up the second try and within about 20 seconds, the check engine light came on again. (Probably the only time I was actually glad that it did).

Now, even though the C.E. light came on, the transmission now seemed to be working very well again - super smooth shifting (which is how it has been since I got it last May).

Pulling the codes, I got 7 instances of 2 different codes: P0068 - Manifold Absolute Pressure/Mass Air Flow Sensor - Throttle Position Correlation
and P0123 - Throttle Position Sensor/Accelerator Position Pedal Circuit High Input.

I figured these were related and looking into both codes, guess what? Faulty TPS was a possible cause for both. Autozone had one for less than $30 and I had a strong gut feeling that the TPS could have been the issue again, so I took a shot at it.

10 minutes later, I started it up and now everything is working perfectly! No more codes, idles fine, starts first try, no more high idling on start, and transmission shifts appropriately.

So now the question is why did it fail 2 times in less than a year? Not sure and will probably just let it go; however, IF it happens again sometime soon, I will start investigation an underlying cause at that point in time.

Mike

 

Mike:
Having a second TPS fail within a year of the first is not common, but not unheard of.
I still recommend that you evaluate your attery with a load test.
If nothing else, it will give you peace of mind and should the battery be flaky replace it.

Don

 

That code could be tps. I have seen that code a few times on 2nd gens and the tps is usually the problem or a vaccum leak. I don't think it's a vacuum as it seems intermittent. If you got a scan tool handy when it acts up check the throttle position. I have seen them at 80 percent at idle witch would cause the trans in limp also long crank times.

 

Sorry didn't read your hole post stating you replaced the tps. Put an oem one in. It will last alot longer.