Hello Durango experts...I hope someone can help me here because I'm totally stumped and out of ideas. Sorry this is long ahead of time but I wanted you to have all of the info. There are no error codes.

I have a 1999 5.9 4x4 with 120k miles. Wednesday I pulled in by friends car Big Truck dealership just to hang out and when I turned to park my Durango suddenly shuddered and sped up just a bit but to the point that I had to jam on the brakes to stop. Backed out and noticed it throttling up as soon as I let off the brakes. When I stopped the whole truck shook, sounded horrible like a diesel engine, bogged down and cut off.

I restarted from Park and it ran fine. When I revved the motor and let off, it was slow to idle down. Because of this, I thought it was the TPS. Ran to AutoZone, replaced the TPS, Cleared the memory on the PCM and restarted. Ran great for about 2 minutes and the back to the same problem but a bit worse. Noticed a squealing noise and then the belt started slipping. Tensioner locked up. Back to AutoZone for new Tensioner and a new Idle Control Motor. Installed tensioner and ICM, reset PCM memory, it ran great for a minute or two, backed out of parking space, drove 20 feet...back to the same issue. When this happens it's all you can do to stop the truck and if you leave it in drive or reverse with the brakes down...it shakes terribly and truly sounds like a diesel engine. A friend suggested putting a ignition control module on and I'm willing to do that tomorrow but I wanted to check with you experts first.

On another note, my driver side power window started working intermittently a few days ago and at the stoplight before all of this happened the alarm bell went off with the check gauges warning. I looked at the gauges and then it went off. I also ran the gauge diag procedure and everything checked out ok.

Any help you have would be most appreciated. I'm in the middle of my Bronco restoration and don't have anything to drive.

 

Is your Throttle Cable Sticking? Remove the Throttle Cable from the Throttle Body, see if it slides in and out freely.
Does ur car have Cruise Control? If you do, Remove the cruise Control cable, see what happen.
I doubt it has anything to do with Ignition. In order for Engine to Rev Higher than expected, you Need more Air and Fuel. Like Vacuum leak, Bad IAC, or Stuck Throttle plate. If the Engine has Rough idle or Bogs down, then i would say it could be Ignition related.

Did you Clean the Throttle Body, and Check for Binding? Like snap the Throttle by hand.

Or maybe your Truck is atually made by Toyota.

 

Throttle cable is not slipping. Cruse control hasn't worked since I bought this truck back in August and I haven't really tried to diagnose because I don't use it anyway. I'll disconnect. The battery has been fine and is about 9 months old but I think my friend has some new batteries in stock. I may just put one of them in tomorrow to test for the heck of it. I've know a bad cell could cause odd problems but really the battery never misses a beat...even under load.

I have checked the vacuum lines and they all appear to be fine.

 

It appears you are having a stoichiometric mixture issue, when you state it starts dieseling. An ignition control module might be a bit unnecessary and overkill, because usually all that does is beef up the spark received at the coil and sends a more solid spark to the plugs.

Since you say you're not getting a MIL that leads me to believe your O2 sensors are operating properly. I'd start by cleaning out the throttle body and replace the PCV valve because both of those can cause real erratic idle.

 

Thanks for your reply Steak59. It actually does idle a just a little lower after it starts doing this...ie after I have reset the memory on the PCM. Yeah I don't think it;s the toyota problem (good one!) because I have checked the throttle cable and even revved the engine from under the hood.

I think something is failing, telling the PCM "Give me more fuel when I engage transmission".

 

Thanks whitewidow00. No the engine is not dieseling...it so loud it sounds like a diesel truck....clang clang clang. And it's all and can do to hold the brakes. Now the RPM's don't appear to be up, rev-wise. It will actually stall now if you hold the brakes down. It's getting worse. It's really strange....I've never experienced anything like it.

 

check the trans fluid level, almost sounds to me like its fighting against a locked up torque converter

 

Transmission problem, maybe? If it stalls in "Drive" when you apply the Brake, or Idles like crap when you brake, it is possible that ur Torque Converter Clutch is stuck apply.
The Clanking noise you heard could be from the Transmission.
Try Brake Torque your Car, Jam the Brake with one foot and Gas pedal with another, just make sure you do it on an Empty Lot or Drive way. If it Clanks even Louder and Faster, It could be the torque Convertor.
The Stall Speed on ur car should be 1800-2300 RPM.

What about the Throttle Valve Cable? the cable that goes from the Throttle body to the Transmission.
If you are dealing with Vacuum leak or other Engine problem, idling like Crap usually throw a Mis-fire code. It might be your trans, it makes sense because you say these symptom only happens when u are in Drive or Reverse.

 

That's what I said. The mechanics at my friends big truck shop (Tractor Trailer) don't seem to think it's transmission related at all....but what do they know? Just joking...but the first think I said outloud when it happend was oh #@$ my transmission. The Throttle Valve Cable is a good idea to check. I'll check that first thing in the morning.

 

On second thought...the TV Cable is mechanical. When I reset the PCM, it runs and shifts fine for a minute or two. After this happens, is when I get all the noise etc...

Also, if I drive it around the lot (Big Lot for Big trucks) it's really fine when I press down on the throttle...even as I start to slow down...when I try to completely stop is when I run in to problems. When stopped, it trys to lunge forward...almost like I'm doing an old school power brake. If I put it in neutral/Park the RPMs are up a bit and then it idles down a bit low but fairly smooth.

My thought is that it is electrical/actuator based issue. Of course I am out of ideas and really appreciate all of your help.

I'm still checking the TV cable first thing.