I have a 97 F-150 4-wheel drive with the 4.6l. It now has 82K on it and has been serviced regularly. I have used injector cleaner every 3-5 fills and have had the system purged a couple of times in the last couple years.

It seems the mileage is getting worse.

I would like to know if anybody else has had this problem and what corrections anybody has done to get better gas mileage??



thanx, D

 

with 82K I'd replace the o2 sensors. Alot of people don't replace these and end up with poor/rough idle, bad gas mileage, sluggish acelleration, or high emissions. It might be time to change the PCV also.

 

Thanx, ya I've changed the PVC a couple of times. I guess I will ckeck into the O2 sensor, but I have heard that its time to change it when the "check engine" light comes on??? Oh well I will have it changed and see what happens. The truck runs great otherwise(not sluggish or rough idle).

Thanx,D

 

You're right most the time you'd know fi the o2 sensors are bad is if the check engine light comes on. Sorry for that. Only other things that can come from my 16yr head is either a bad fuel/air mix which can be from a dirty filter or since you run a K&N you might be over oiling it possibly? Also worn plugs can result in bad gas mileage. Sorry if this ain't much help but hope ya get it fixed asap!

 

If you still have the origanal plugs in I say change even though you should go another 18,000 miles yet I say they probable are about shot.

 

I get about 10 mpg in town (12-14 on the highway), if that makes you feel any better. I've been trying to boost it up and was able to get around town up by about 1.5mpg and highway up about 1 mpg with the power programmer. Only thing is that the programmer costs a nice little chunk of change and then you gotta run premium. I'll make you a deal and sell you mine for $200 (used once and cost me $375) since I'm about to get gears anyways and the power is no longer an issue... Other than that, can't help ya...

 

Just a thought. Blocksbikes is a fellow Canadian. It appears to me that maybe his truck has 82,000 kilometers, just over 50,000 miles. Does this impact any of the advice re the PCV or O2 sensors? I am interested as my truck is approaching 100,000 kms, or about 60,000 ,miles and I have done neither. Thanks.