i have a 2000 durango with the 4.7 liter engine. it has about 115,000 miles on it. lately, the rpm's would bounce up and down when it idled, and sometimes it would shut off when i came to a stop. i replaced the air idle control valve, cleaned the throttle body, and replaced the throttle position sensor. this fixed the rpm problem, but sometimes when i stop, the rpm's will go up around 1000, then drop really low, or sometimes the car will even shut off again. this only happens when im stopping from low speeds (25-35mph) and at stop signs, i never notice it at stop lights. does anyone know what could be causing this, or how to fix it?

 

Long shot how about 02 sensor? perhaps a bad injector or fuel rail pressure? have you checked basics? like plugs?

 

checked everything other than o2 sensor and injectors, something new is happening now though, when i'm driving, the oil gauge will be about 3/4 of the way to the right, then when i stop, and keep my foot on the brake, it starts to decrease and settles just below the half way point. when i start moving again it goes back up to 3/4, idk why it would do this

 

That's normal John. As long as you don't go to 0 pressure or close to it you are fine. How did the plugs look? How about cylinder pressure and fuel rail pressure?

 

plugs and cylinder pressure are good, idk about fuel rail pressure. i thought the oil thing was normal because it does it on my other truck, but i just bought the durango, and ever since i bought it the oil pressure never changed, but i just changed the oil and i started to notice it, so it worried me a little, not because the pressure was too low or anything, just because it was out of the ordinary for this car

 

had the same issue on a chevy one time looked everywhere turned out it was a loose battery connection worth a look also make sure the harness that goes to the coil is ok

 

That's a good point a lot of diveability issues can be caused by poor coneections or a bad battery. Definitely look into that.

 

+1 on the battery. Couldn't tell from the post if the issues were cold related after a fresh start or if it happens all the time. With everything already swapped, it's the battery. Anyone new to D repair would think we are nuts... and that may be correct... however that doesn't change the fact the battery is more important to low idle runability that most realize.

IndyDurango

 

not cold related, i live in socal, so the lowest it gets here is like 50 degree's anyways lol. thanks for the help guys, i'm going to put a new battery in tomorrow and hopefully that will fix it.

 

John before replacing the battery take it down to auto zone they will test it for you for free. When you are running at idle it puts a load on the battery if the alternator can't keep up with the electrical demands of the system. That is why a battery is a good starting point but always test rather than throwing money at the problem. They can also test your alternator. This could be your problem if it is undercharging your battery.