For the past 10 tanks I've been getting a recorded straight 13mpg. Even driving like Grammy I get 14 or 15mpg. What's a good place to start looking for the culprit? I have a Flow 40, and FRAM high flow air filter. Fuel filter is new, plugs and wires are new, oil is recent, oil filter is recent, no known exhaust leaks, good tires and I keep them full at 35PSI.

I kind of suspect from the noise under the hood when revving I have an intake leak somewhere, but does anyone have any hints on finding the sucker? I don't want to just take apart my intake and rebuild it, but I think it's probibly from the throttle body back, if it's an intake leak. Is there a good way to check for intake/exhaust leaks, if so, what else should I check to boost mpg?

 

Start the engine and spray WD-40 around any area you think might be an intake leak. If the RPM's increase, you found your leak.

 

clean the throttle body and maybe new o2 sensors. how many miles are on your truck?

 

51k

 

hmm just turn 190k here on my 94 3.0 gettin 18-21 mpg in mixed driving.. and its all stock..

get some carb cleaner and spray around the t-body and around the intake while its running, if the engine revs when you spray it then you found the leak..

WD-40 isn't as combustable and won't work as well..