Hi all, new to the forum and trying to find a fix to what appears to be a common sympton to 2001 Durangos.
I have a 2001 Durango with the 4.7L, I'm the original owner and it has 107K on the clock. This problem started several weeks ago which the idle wasn't stable, it would surge as high as 2 grand and settle back to 700, then 1200 and back down. Sometimes it would hang around 2,000 and blipping the throttle wouldn't help. It would also do this regardless of engine temp.

Since the vehicle wants to lunge forward at intersections or behind stopped cars in traffic it was proving to be an unsafe condition to live with so we decided to take it back to the dealer to get the problem looked at.

They claimed an Idle Air Control Motor was defective along with the throttle body in need of serious cleaning and a dirty air filter, they also suggested a 3 Part Fuel System Cleaning as well. Knowing these things except for the Idle Air Control have nothing to do with the problem I figured it wouldn't hurt based on it's age and mileage. While being repaired they called to inform me the tech was getting fluctuating voltage readings from the Throttle Position Sensor as well and they wanted to replace this to which I agreed to, the only problem was they didn't have any Mopar ones in stock and it would take several days for one to come in however they could immediately get me an aftermarket one so we went that route so we could get this back in a timely manner. They call to say it's all finished and running/idling great so we go pick it up. While at the dealer to leave it starts to surge again! The tech comes out with his portable computer, plugs it in and it dislpays the readings from the sensors while it's idling, to which it starts behaving itself and stays idling at 600 to 700 rpms. The handheld was showing 0.51 volts being read at the TPS and he says thats what it's suppose to read. He says he'll clear the ECM so the car isn't running from past conditions and says that should do it. We take it for a spin come back and it's still idling fine, it runs great and idles perfect the ride home and for some errands made with it later that day. The wife takes it to work that night and coming home about 15 miles from work it starts to surge again, I mention the 15 miles to indicate it was at operating temp. The next morning we start it and it starts surging again, this time it's NOT at temp then it starts idling fine and stays that way.
I searched through the threads about this problem and it never went past the IAC or the TPS, there was mention of possible vacuum leak but no specifics to where and if this really was the cure. I'm already $500 poorer from the dealer in both maintanance and trying to solve this problem and I don't want them to continue to play "eenie meenie minee mow" with my wallet since there's no warranty anymore.
Has anyone solved this problem even after the IAC and TPS has been replaced?
Thanks for any help!

 

the tps is the most common culprit for this problem, they are correct on that point, the rest was stuff you could have done yourself in about 30 min for under $100 (iac motor and a can of intake/carb cleaner)

it is POSSIBLE that the tps was faulty out of the box, you could try demanding that they replace it with a new one at no cost to you as the part was faulty, but also check the wire harness for any loose connections or shorts on the plugs and going to the computer

 

Thanks for the tip, unfortunately I had shoulder surgery a month ago and there's not too much I'm able to do at the moment mechanic wise. In fact I had to hurry up and replace the front drive shaft due to a worn out CV joint and I did this the weekend before surgery. Then this problem cropped up afterwards and it seemed too unsafe to let it go until later.
Anyway, while the tech was under the hood with it running and holding the computer, he was pulling on the wire harness and plug going to the TPS looking for fluctuations in voltage and changes in idle but it held steady on both counts. He made a mention that if it continued that he would recommend the Mopar one, although I noticed in past threads about this problem people were buying them from Autozone and seemed to have no problems so who knows. I may be forced to do this for the sake of ruling it out.

 

Those freaking hurt don't they? I've done it twice!



Tell them to pull it out and stick in a Mopar one and also the IAC in Mopar as well.


I never had a single issue with my Auto Zone one but when trying to find a weasel it is better to go OEM and force his head out!

 

[quote=hydrashocker;2030795]Those freaking hurt don't they? I've done it twice!



Yes they do! I couldn't imagine doing it twice!


The IAC was Mopar, if it continues I'll replace the aftermarket with Mopar as well and go from there.

Thanks for the info guys!

 

So is the surging only when the transmission is in gear?

 

No, it will surge either in gear or in Park.

 

I wonder if it could be water in a coil pack... never heard of the problem on the D but I had a friend with a GMC that something like this happened to it.. you might just be able to unplug each individual coil back and see if the engine smooths out while running 1 cylinder short.. just know that it will be a little ruff because its one cylinder short.. I kinda doubt that's the problem but it wont cost a dime to check for a bad coil pack..

 

I'm with Sum ^^^^^ on this one.

 

The idle never dipped below it's normal 600-700 range, it would start to drift too high. As far as running wise it runs like a top, just as good and strong as the day I bought it.

Since my original post of my problem, 2 things changed with it. After the tech reset the computer to clear out any old settings, the next day the engine light came on so I pulled the codes to see what's up and it was the P0601 code which according to the code list is Internal Controller or Computer Error?
Second thing is the wife calls me at 12:30am when her shift ended to say the car won't start, meaning it wouldn't crank and lights were dim. Luckily a co-worker was able to jump start it to get it home. Now it does still have it's original battery and we bought the Durango on Sept 10, 2001 (easy date to remember) so I have no doubt the battery is shot and the "eye" is black. Interesting point to note here is since that night she started taking my Altima to work, since I'm out on disability at the moment, and we've been keeping the Durango in "dry dock" until I change this battery and it's been starting up for me everytime and spinning the engine rather fast I might add with this "bad" battery. I'm in the process of hunting down in the area a dealer for Interstate Batteries that stocks the Mega-Tron Plus 85month battery for it. I don't know who makes batteries for Dodge but kudos for them on this one!
Yea, I'm seeing the common factor with the Durango too, the wife!

At any rate I'll get it a new battery and as far as P0601, I'm on the fence. Some older posts says replace ECM or PCU or ECU (it seems to have several names) others said it's a general fault code that doesn't really mean the computer is bad.