I have a 95 150 XLT 2WD that only has 72k on her. I'm 3rd owner and the 2nd was my little old man Father. He never did anything to it but "tune it up"........(aka someone took his money!) Back to the issue at hand;

Lately I have noticed a decrease in fuel economy here in Charlotte where I live combined with a lack of power. Power loss is generally under a slight load when mildly accelerating. (3/4 WOT)

I've replaced the air filter, plug wires, dist cap & rotor. It has good rubber on it and no noticeable vacuum leaks. Fuel consumption is down about 5% which I've noticed because when I used to get 200 miles/tank, I'm now getting about 180. Plug wires were original and were sitting on the valve covers so htey were replaced. I'm sure the plugs have been replaced also during one of it's "tune ups" so I didn't bother with them. I've had it for about 10 months now and drive it back and forth to work which is about 15 miles round trip.

This one has me mystified so I'm asking all of you out there to help a new FoMoCo owner in solving this. I'm more of a GM man but my Dad sold this to me fairly and it's a good looking truck. I just want to get the most out of her.

Any feedback is appreciated.

Mark

 

When did you measure the 200 miles per tank? The reason I ask is that the change to the 'winter' blends of gas could cause the decrease you describe, as will excessive accelerating at 3/4 WOT.

As to the loss of power, does the 'check engine' lamp come on while the engine is running? If so, suggest to get the computer codes pulled. One other thought is a plugged cat (thinking along the lines of airflow restrictions), although with only 72K miles, it would be early for such a failure.

 

Yes that is one consideration. That's what I thought it could have been also. As of today, I replaced the thermostat (wi 180, old one stuck on me recently) while I was at it, I actually replaced the plugs too. They appeared frosty normal)There are no obvious vacuum leaks. I considered ripping out the throttle body bypass AND the oil cooler bypass. However, I think for now it's best to leave them as is. No need to complicate things.

It IS NOT blowing any codes.
Gas mileage check has been in the last 4 weeks. I average 210 miles/week.

The description of the problem could also be put as stumbling at lower rpms and speeds between 25 & 75 % of WOT. At cruising speed she'll open up and won't stumble. It's the slower around town driving where it shows up.

I'm open to any other suggestions.

 

A clogged cat is possible, but I'd think the problem would be worse if that were it. Did you pull all of the plugs and check them? I'd do that if not. Of course, if you are going to the trouble of removing them, then it makes sense to replace them. Stick with Motorcraft. Also, do you have a timing light? If so, you might want to check the timing too.


PS-
Welcome n00b!!!

 

D'oh! I gues that answers the plug question. Try the timing, and the cat. I'm not sure how you can test a cat though. There was a post recently about holding your hand over the exhaust, but I don't recall how it goes...

 

Sh***t! I threw out my timing light YEARS ago! (I'll have to borrow one from a co-worker) I'll get back to you on this. Never woulda thunk it so why not?!

 

180 stat? Isn't that engine control system designed to use a 192 or 195?

 

HI MARK
I will tell you a story.
My problem started about the same way.
Same model same motor 300k + miles at 110 miles a day.
Two years and 3 thousand dollars later, it is a lot better.
The best I have been able to put together is something like this.
The heater core failed than the radiator, in the meantime the
ox sensor was covered with oil, at the same time both air flow
sensors died. I do wonder if the radiator was plugged or just too much heat.
It started, with a loss of power than more fuel, (-10 +20 precent not uncommen)
(later a some times backfire) (after it got worse).
Guess the combined effect of the ox and airflow sensors
kelp it from giving codes.
It passed exhaust emissions testing two mo before becomming undrivable.
The backfire caused the rubber in the harmonic balancer to shift.
another 700 dollars. Shifted about 40 deg.
The ford place that had done the original work (and could not find the problem early on said .
Ford said That it was worn out and get another (for the balancer problem).
Also replaced the cat and muff "no effect", "original ford advice".
It took three shops two independents and the last a different ford. (with no computer )

Advice find a shop that can check each of the sensors while the
motor is running, better, being driven, Under your conditions.
A good shop will talk about their findings, and ask guestions.

Now it needs rain tires, I went to the "tires place here" They only talk of off road.
There is a seperate place for off road. It would be nice if they were only there.

wrong100

 

So was the balancer the main problem, or was there something else? Sorry if I'm dyslexic, but I'm curious what actually fixed your problem.

As for rain tires on a pickup, I'd use A/T rated tires, like BFG A/T's. Those tires offer legendary traction, and are exceedingly popular, so they are pretty reasonably priced. A friend of mine just got 4 31" BFG A/T's locally for $125 each installed.