Mechanics

POOR MILEAGE

2003 Dodge Dakota

Engine Performance problem
2003 Dodge Dakota V8 Four Wheel Drive Automatic 37870 miles

After 30K maintenance service, mileage dropped from 17-24 MPG to 10-11 MPG. Every few weeks I get a MIL check light (steady) with a P0441 code. But by the time I bring in to dealer the light has gone out. Dealer mechanic checks sensors and hoses and lines and runs NVLD test, no problems. No gas seen in evap lines, inspected hoses look okay, no vacuum leaks. So nothing gets fixed. In a few days or weeks the MIL light will come on again. Otherwise, the engine starts and runs fine, only the fuel economy remains abysmal.
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Hercg
April 28, 2008.




I dont think its related to the code 441. Evap system has a problem and unfortunately you need the problem to happen to diagnose it, but the dealer should atleast make a attempt to repair by atleast replacing the evap flow sensor if all else checks out ok.
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Tiny
Mastertechtim
Apr 28, 2008.
So does that mean the mileage will go back up to normal if the check condition is cleared? Doesn't the ECM/ECU adjust the mileage downward when there are problems?

Tiny
Hercg
Apr 29, 2008.
I have never heard of this type of code causing lower fuel mileage so I cant honestly say it will get better by fixing that code. I wish I could be more help

Tiny
Mastertechtim
Apr 30, 2008.
After getting nowhere with the dealer, who made the suggestion that Blue Planet gas was causing my mileage problem, I played a hunch that it might be caused by the injectors, and added a can of SeaFoam to the tank right before my next fill of gas. Almost immediately, my mileage went up, and within a week had increased from 10 to over 15 MPG (city). Whereas my fuel gauge needle used to plummet every time I turned on the engine, it now stays pleasantly up in the three+ quarters full range for a good part of the week. I don't know what the WB
dealership might have done to cause or exacerbate this problem, but I feel that the SeaFoam has rectified the situation, and now I don't care. I should now be able to drive to Wausau, a 180 mile trip, on less than half a tank of gas, as I could before the 30K maintenance (dis) service performed by the dealer. As a general tip for others, beside checking the O2 sensors, make sure the injectors are NOT gummed up, as you will definitely lose gas mileage. Three cheers for SeaFoam. No kudos to Dodge dealers, sorry...


http://www.2carpros.com/forum/automotive_pictures/184211_Picture_001_1.jpg


Tiny
Hercg
Jun 6, 2008.

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