Couple of questions guys or gals---1999 Dodge Ram 1500 4x4 .9 Off Road package....terrible gas mileage, If im getting 7 im lucky, I drive 55 dont romp on it etc etc, any hints on improving.....truck has 160,000 excellent shape looks as good as new, smooth idles no backfire lugging or anything, on it but i have never owned a vehicle that did so bad on gas Fords GMC etc etc...I did notice a whistling from around the carb area only briefly during acceleration, i havent tracked it down yet but im sure its up at the carb somewhere, sounds almost like a supercharger on a semi just on aceleration then it smooths out,its really kind of a cool
sound. I have a ton of questions but lets see how ya do with this, point me in the right directions
Thanks

 

lets see. plugs, cap, rotor, timing, air filter, fuel filter, any other basic tune up stuff could help. Throttle body could need to be cleaned. What about changing Cat's or putting a new exhaust system on there. does it gett better gas milage over the summer than wingter. In the winter the gas has different additives in there to warm the vehicle up quicker and equates to crappy gas milage. I have been getting 13-15mpg average in the winter with my Grand Cherokee but I have the 5.2V8.

Fist thing I would do if I was you was do all the basic tune-up stuff that I mentioned above.

 

Sounds like you've got a bad vacuum leak somewhere. That would account for the whistling noise.

 

swap out the o2 sensors with NGK's (dont use Bosch, they dont work well in the dodge for some reason), get the NGK plugs too. I'd check the plenum gasket to see if it's leaking... look down the throttle body with a flashlight and look for oil pooling on the bottom of the intake manifold. if this is leaking, it'll kill your o2's and your mpg. fix the vacuum leak that you have near the throttle body. most likely the air filter housing is not seated well. swap it out with a cold air intake kit...

 

I actually look down the inside of the throttle body or the outside, its just a quick whistle of air im almost positive its on the back of the carb but i sprayed wd40 around it to get it to stall but no luck

 

look on the inside...

 

I read in another post that the throttle body seals are bad about drying out and falling out, making a loud turbo type noise. That may be the noise you're hearing.

 

I haven't verified for sure I'm just kind of estimating but I think I'm getting anywhere from 7-9mpg and I have a 01 1500 4x4 off road package but I also have 33X12 tires so that doesn't help it I'm sure.

 

I did talk to the mechanic at my dealership today he was saying same thing about O2 sensors they are probably bad and have put air fuel ration outta wack will replace and not use Bosch as recommended. As for the air sound in my intake it appears that i have solved that by realizing that the gasket that goes under the airbox is missing(i think the monster 5.9 ate it when it was hungry for gas) so it will solve that but I still have the questions regarding the foglight, is there a fuse anywhere that i cant find, just one day quit, both lights no cracks or frayed wires, checked all the fuses i am aware of all intact.....and also i was thinking of a exhaust system any idea'S....ireally like this forum............ seems we have quite a few that know their crap on here....key focus now is exhaust and foglights

 

Read this thread, may answer a lot of your exhaust questions...

exhaust thread

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