well i will say first thing i think i know the problem...the truck has 297k on her ha ha


but here is whats going on. i moved from MI and on the sec trip down i was hulling my 26' enclosed trailer with it loaded down good and in west Virginia i stopped for gas and when i left the truck ran good but going through the mountains it just could not hold it's speed at all. so i though it was just bad gas. so the next fill up i put some 93 in it and same thing.

on the truck i have a free flowing exhaust and a cold air intake.
so i was on a mission to find out whats wrong. i knew it needed plug's so i went ahead and order a set of stock motorcraft plugs and a full set of coil packs "aftermarket"
when i changed them i checked the comparison and i was between 127- 144 across the board. changed the fuel filter and check fuel psi under load. still was lacking. i then pulled the cat because it looked like the factory one. i removed it and looked like new. it burns only 1/2qt in 3k and other then the low power it's a nice running truck. empty i get 13-14 mpg. is the old girl just wore out? i need her to last a little longer but i dont want to hull my trailer because i dont want to kill it.

thanks for listening

just for the heck of it my truck



before the front end swap

 

I had a similar problem on a, i believe 1999 f450. It turned out to be a worn out fuel pump. Good Luck!

 

Nice looking truck, 99?

Have you checked all the normal stuff, air filter, fuel filter, fuel pressure on the rail?

Have the plug been changed in the last 100K?

How high are you getting? You loose 3% HP every 1,000 feet over see level.

 

this is a lil off topic but where did you get that front end it looks nice

 

truck is a 99

all the stuff is good. like i sad in post i just changed the plugs and coil packs,
air filter is like new and just changed the fuel filter, what a good fuel pressure on these?

and i dont know how high it gets. but like i sad it ran good the first trip down it was after i stoped on the sec trip when it started like some one flipped off the top 75 hp switch lol...and i did not know you lost that much hp.

now this is just a though but on the big trucks we have a like a barometer pressure sensor that reads at high altitude to adjust the fuel map and other things..dose ford have the same thing? could this be messed up?

and ...matt777

i worked at a body shop part time to hale out a friend and the grill was off a 05bharley davidson edition truck and i had to do alot of work to it. the head lights were off e-bay "cheaper then i could buy them through the shop" and the bummer is a stock 05-07 out of the after market book, just got everything painted instead of chrome, and brackets and all are off a 05-07 just had to drill out some holes. i used the stock 99 header panel but had top mod it heavy. if i had the cash i would of just got a 05-07 one but it was $150 more my cost.

 

Good fuel pressure is 38-39 PSI I believe, make sure it stays up when you get in the gas too, not just at idle. Test it using the port on the fuel rail.

I don't think it uses a barometer, I thing the MAF does that, but don't quote me on that.


Those of us with the 97-99 V10s have the least power full version made to start with too, which cant help.

 

yea i just checked the fuel pressure driving up are road in the sub. i am hooking up the trailer sunday to move something so i will hook it up then "i have a long lead" i was getting 35-40 last time but not really loaded.

 

How much is your mileage suffering?

 

great job looks really good wish I could do that to mine

 

empty i have been getting 13-14mpg loaded it really is sucking. last time hulling a my 02 blazer i was getting 6-7mpg

i was board today so i hooked up the good old gauge and went for a drive. at idle around 32psi. then around wot it jumped up to 40psi so i am good there. i am thinking it's just a sign to get my diesel

but i was hoping it was something i was just forgot about.

 

What do you have for gearing and have you towed a heavy load through the mountains before? Your gas engine will loose power as you gain elevation. By the way the truck is squatting in the first picture you must have an awful lot of tongue weight. My 5th wheel has 2300# of hitch weight and it does squat down nearly that much.

Just a thought.

Rob

 

With $2000 and some work you can get the power up to what a 3V 05 V10 has.

 

Looks like a dependable old truck, hope you get her fixed up and she lasts another 200,000 for you.

 

thanks rob for the ideas
and yea my first trip it was loaded about the same as the sec trip "the pic was from the first trip" in that pic the tongue weight was a little to much because i had my tool box loaded "matco 3 bay" up front because thats were my e track is and in the rear i dont have good of hook points for something like that. most the time with my blazer it dose not even look like it's loaded. the sec trip is were i seen the lack of power dont know if the first trip did it in. it would not maintain 60 in the hills...some i was as low is 50 mph. and i have never checked and seen what gear i have i am thinking it's high because at 70 i am around 2,300 rpm so i thing around a 3:73. even empty it's lagging and i kind a wish i got a v nose because that may of helped to.


but since everything is checking out i may make the one trip i have left. just have some stuff left on the barn and other things. it will be a light load..it's just a long trip.

i know the miles is high so i just dont know what i want. rebuild the v-10 or do the cummins swap i want. i am a diesel tech and feel out of place driving a gas but at the time it was all i could pay for and it's been one hell of a truck.




and just because i can here is my blazer...lol

 

Swap a cummins in? that would rock, but think of what you could do with the V10 for the same money.

BTW, nice Blazer.