I've been having an occasional problem with a "sputtering" engine on my 1999 Dodge Durango 4x4, 5.9 liter, automatic, 225000 miles.

Here's the scenario: ......The engine does great when I am accelerating or cruising at high speeds. A frequent problem then occurs when I let off the gas in order coast through a yield or come to a stop. At a stop the rpm will drop low and the engine will sputter and it will the go back to normal and will run great once I accelerate again. This problem only occurs when I am at a stop, when I’m in parked, and when cruising at <10 mph. It does not happen all the time but it is getting worse and is doing this more frequently. When I am also at a stop there is some mild fluctuation in the rpm (going up and down only mildly). For example, it idles at about 600, so the rpm gauge will fluctuate to a high 650 and low 550. I am not getting any "Check Engine Light." The other problem is that the truck will stall when in reverse during cold starts and after it warms up it have no problem reversing. It only does this when it has been sitting for awhile.

Here's what I've tried so far: ......Installed new plugs, cleaned cap & rotor, installed new Idle Air Control Valve (IAC) & Throttle Position TP Sensor (TPS). I have recently just replaced the pcm too. I also had a remanufactured transmission put in about 2 years ago and the truck shifts just fine. I’ve read that it can be an torque converter problem due to some of my symptoms

Any advice-help would be appreciated. Thanks!

 

my durango was doing something similar once, the revs would drop low and it would occasionally stall while going slow. The problem turned out to be loose battery terminals. Check to make sure they're tight and making good contact, as well as check to make sure the battery is still good

 

since you already replaced my top 2 suggestions (IAC and TPS) im going to suggest looking at the battery, take the erminals off and clean them real good, then put em on nice and tight, if that doesnt help look into a new battery, avg lifespan of a battery in these trucks seems to be about 4 years

 

To: shrpshtr325 and that_guy
I just went to Autozone to check the battery and the battery was perfect. Plus my battery meter stays at a constant 14V so I dont know if this is a battery issue. Thanks for the suggestion though.

 

check the terminals and make sure they're not corroded, make sure to check the terminals where they clamp onto the wires too. If they are, clean them with a wire brush or even replace them. A bad connection to the battery to cause this issue and if it is the problem it's a relatively easy and cheap fix

 

When you installed the new Idle Air Control Valve, did you verify it was working? You should be able to feel the IAC solenoid vibrating the valve open or closed slightly to maintain engine RPMs.

 

+1

Clean the battery posts and terminals back to clean new metal.

 

To: that_guy and hydrashocker
Well I cleaned the terminals and the rpm did not drop low real low like before when I took it for a test drive. But the rpm still fluctuates mildly when it is at a stop as if it wants to drop low. The fluctuation is very mild though.Example, my truck idles at 650 and the rpm gauge will drop to 600 then bounce back to 650, that's how it fluctuates. I can tell that when it does this the engine fells like it wants to sputter but the rpm doesn't fall enough like it did before I cleaned the terminals. The truck also still stalls in reverse on a cold star

 

To: ZCR1
How do you go about feeling that the IAC solenoid is vibrating? Do you just feel the back of the IAC and see if it is vibrating because the engine also vibrates which vibrates the IAC, so I dont know if the IAC is vibrating.

 

i would guess you got a dud TPS sensor, take it back and have them exchange it.