Dodge Durango Forum II

Idle questions

I have an '01 4.7...the truck gas mileage has gone down hill in the past couple of months. With 30,000 miles on the truck I decided that the plugs needed changed, the idle was hunting a little so I opted for the new TPS and I cleaned the TB. This was a couple of weeks ago...one of the other things that was happening on first start in the AM with the cooler temps was the truck would falter and hesitate at idle and then the rpms would jump to about 1500, settle down to normal and then all was fine...occassionally it would stall but just once or twice...ove the past couple of months the idle has settled at about 500 rpm in drive, where it seems to me it used to be 600 or just a touch over 600.

I did the plugs, TB cleaning and replaced the TPS...no change in the gas mileage,the idle was hitting about 600 and at times was 500 but steady...

this morning I started the truck and it stumbled, hit about 1500 rpm, settled down and was ok...at lights though it feels a little bumpy in the idle, very slight but not smooth as it seems to be normally. I also noticed on monday night as I hit WOT that I had some pinging... never has it pinged...gas is the same company as always, I had filled my tank earlier in the day.

The Questions...

On the TB there is the TPS and then also the? What was the other thing I saw when I cleaned the TB...is it a part of the idle circuit...can you name it and give signs and symptoms of one possibly not functioning at an optimum?

Why no change in the gas mileage...I used to routinely get 16+ mpg...I am now lucky to get upper 14s? Any suggestions?

The pinging? Could be a less than desireable tank of gas, but NEVER has that been a problem...

Thanks for the help...

Craig

Wed Sep 22