Robert T

I have an 05 F150 and for about a month i smell raw gas as the air blows through the defrost of regular vent cycle. when on in cab circulation the smell is not present. all hoses are good, no leaks around rails or injectors and fuel cap is good. any suggestions?

Good old Bill

Obviously the engine is running, but no signs of leakage. Interesting, brain is dead at this time, good luck.

sparks

i too had the gas smell after the plugs were changed. i went back and had my mechanic check all the plugs and sure enough one was loose, now no more smell.
so this may or may not be your problem but it is worth checking anyway.

primalurges

Leak is definately in your engine compartment that's why your not smelling it in recirculate. Fuel injection systems usually have a vapor return line which send fumes to a carbon canister and possibly back into the engine to burn off. Perhaps your leak is gas vapors from this system and not actual liquid gas which would explain why you cant find the leak. Check all your hoses going into the manifold, fuel rail, and see if you find a hose other than your fuel hose that may be headad back to the tank or back of the truck. Good luck

Robert T

Hey thanks for the contact. I sent it to another dealership who actually had diagnositc capibilities. They determined that the autolite spark plugs do not work well in the 5.4. I had put them in myself at 45000, this has been diagnosed this with "many" other vehicles they have worked on. Per a TSB(trouble service bulletin) posting, they replaced the throttle body and reprogrammed the PCM and updated the TCM (trans) because i was experiencing transfer case shifting problems. They also replaced the o rings on the fuel injectors. Then they pulled and inspected the exhaust headers for any additional problems. Since the winds have died down enough these past few days i have not noticed any smells as before, so i feel the problem is solved.
I will keep you all posted if anything else developes. Just fyi, the truck is still under extended warranty (75000) so thank goodness i did not have to pay for all this work. thanks again.