I have had my 96 Dakota (318) in for a diagnostic check for surging at 45mph---they reset my timing from (they say) 9deg retarded to factory spec of TDC. The surge continued and gas mileage went from 17mpg to 12mpg. Transmission died the following week and $3000 later with new trans the surge is gone but the mpg is still 12. I asked them to reset the timing back to the 9 deg which they did under protest. My mileage had not improved at all however. I was alway trained that timing needed to be advanced for better mileage--I would like to have Dodge set my timing to 5 deg advanced, but hate to keep paying them without a second opinion. I would appreciate any input from anyone who knows the correct answer. thx

 

Timing on these motors is controlled by the computer (as you probably know).
With that being said, a few people have stated that you can make slight adjustments to the timing by moving the crankshaft position sensor. This is located between the engine and transmission on the passenger side. I've never done this, so... I don't know much more than that.

 

Thanks for the info, but I would still like to know if I am correct in my understanding that advancing the timing is the right direction to go for better mileage

 

Yes, incorrect timing can have an effect on fuel efficency.