1999 2.5 no power

help 99 2.5 no power when load applied and when the a/c is on forget about it, new plugs and wires and no burning of oil, blow bye or washing, the other odd thing is that no matter where the a/c or heat is set meaning out of the panel or floor etc when placed under load it quits blowing from this location and blows from the defroster location and once i come back down to cruising speed or level out ( no load ) the blower returns to the orginal setting, dash, floor etc. it is pretty bad, just going up an overpass causes all these headaches and it is hard to maintain speed on a incline such as an overpass. i am thinking that this might be a vacuum issue could it be a worn cam causing all my problems or a stretched timing belt please help the lack of power is killing me not to mention my a/c blowing in the defroster location thanks to all mike

The problem does sound vacuum related. A simple check would be to hook up a vacuum guague to the intake manifold.

The problem does sound vacuum related. A simple check would be to hook up a vacuum guague to the intake manifold.
hey thanks for the reply i hooked a vacuum gauge up over the week end and it is rock solid this on is throwing me for a loop no fluctuation or consistant drop please help thanks to all again mike

Bogging the engine could be caused by a bad compressor.

Is this an auto trans?
Does the problem happen regardless of A/C on or off?
Vent change could be due to lack of vacuum because engine isn't running well.
How many miles on the truck, has the fuel filter been changed, inspect the air filter and intake tubing.

hey thanks for the reply everyone it is a 5 speed 750000 miles and the filters have been changed and the intake is a new K&N i change all fluids and filters at or before mfg specs and yes it happens all time no matter if the a/c is on or off if just the vent or heat is on the same thing happens the blower quits blowing from the original setting and blows from the defroster position, once the load has passed or i let off the thottle the fan blows from the original postion i hooked the vacuum gauge up and it is rock solid the only thing i can think is that underload or wide open throttle there is some kind of intake leak or vacuum leak and at idle this problem does not present itself and if i give the throttle a quick snap everything seems ok according to the vacuum readings i also thought that a possible a weak valve spring or two may also be the problem i am lost the lack of power and the blower thing i am gonna lose my mind but thanks again to all and i am open to all ideas even a bullet in the block sounds good right now lol thanks again mike :banghead:

put your old intake on and see if problem disappears. could be cracked, loose, obstructed. check your MAF sensor and wiring.

the intake is the original ducting and airbox i just put in a K&N replacement air filter all the ducting is tight and clean inside and out the MAF is clean and all the wires seem snug the same with the IAT last night I borrowed a buddies covered trailer, tiny little thing, just enough to put a 4 wheeler in, and while hauling it home i had trouble pulling it, we are talking about a trailer i can pull around by hand. I could not use 5 th gear and had trouble staying at 50mph in 4th when i would come to an overpass i would have to hit 3rd and chug along at 40ish i cannot figure it out does anyone know what happens when one of the coil packs goes out, would it run without a mis, or not at all. i have no codes or check light and i hooked up a flight recorder and it logged nothing, the blower blew from the defroster position the entire ride home even though i had it set to blow onto the floor i am inches from ripping this motor out and going to a v-6 with a carb and getting rid of all this computer crap thanks again to everyone that is trying to help mike

the intake is the original ducting and airbox i just put in a K&N replacement air filter all the ducting is tight and clean inside and out the MAF is clean and all the wires seem snug the same with the IAT last night I borrowed a buddies covered trailer, tiny little thing, just enough to put a 4 wheeler in, and while hauling it home i had trouble pulling it, we are talking about a trailer i can pull around by hand. I could not use 5 th gear and had trouble staying at 50mph in 4th when i would come to an overpass i would have to hit 3rd and chug along at 40ish i cannot figure it out does anyone know what happens when one of the coil packs goes out, would it run without a mis, or not at all. i have no codes or check light and i hooked up a flight recorder and it logged nothing, the blower blew from the defroster position the entire ride home even though i had it set to blow onto the floor i am inches from ripping this motor out and going to a v-6 with a carb and getting rid of all this computer crap thanks again to everyone that is trying to help mike

SAME PROBLEM WITH MY 2.5 RANGER, 5 SPEED.
HAVE YOU CHECKED THE FUEL PUMP?

the intake is the original ducting and airbox i just put in a K&N replacement air filter all the ducting is tight and clean inside and out the MAF is clean and all the wires seem snug the same with the IAT last night I borrowed a buddies covered trailer, tiny little thing, just enough to put a 4 wheeler in, and while hauling it home i had trouble pulling it, we are talking about a trailer i can pull around by hand. I could not use 5 th gear and had trouble staying at 50mph in 4th when i would come to an overpass i would have to hit 3rd and chug along at 40ish i cannot figure it out does anyone know what happens when one of the coil packs goes out, would it run without a mis, or not at all. i have no codes or check light and i hooked up a flight recorder and it logged nothing, the blower blew from the defroster position the entire ride home even though i had it set to blow onto the floor i am inches from ripping this motor out and going to a v-6 with a carb and getting rid of all this computer crap thanks again to everyone that is trying to help mike

JUST SITTING HERE THINKING---COULD THE TIMING BE SO FAR OUT THAT IT COULD CAUSE VACUM AND POWER ISSUES?

well this is odd the truck ran pretty good this morning but it was 44 degrees the truck ran smooth and had some decent power well at least to what i have had the past couple months anyway the truck ran pretty good the blower still would blow from the defroster position under heavy acceleration any ideas i thought maybe IAT no go it checks out ok so any other ideas would be great thanks mike

It ran better in 44degree weather? Only when the truck was still cold? Or, did it continue to run better even after the truck was at full operating temp?

ran good the whole time into work this morning it is warmer out now so i can only imagine it will be back to normal on the way home i will let you know it is just driving me crazy the truck ran good but still under a good acceleration the blower stops blowing from the designated position and blows from the defroster

Try removing the line that feeds the vacuum resevoir/heater controls from the intake manifold and then securely plug the port on the intake.
This will isolate any possible vacuum leaks occuring in the circuit from the engine. A small vacuum leak can sometimes only be noticed on acceleration.

ok this is just great now i am getting some pre ignition or detonation under acceleration in 4 and 5 gears i may have it in lower gears but the motor gets pretty loud i have heard it in 3rd though so now i am really stumped

vacuum leak can cause spark knock.

ok it has been cool in the mornings for about two weeks now and the truck has ran like a well oiled machine but in the afternoon it warms up to mid 70s and the truck runs terrible

Check the resistance and voltage drop of your engine coolant temp sensor.
50degF---58,750ohm with 3.52v voltage drop
68degF---37,300ohm with 3.06v voltage drop
86degF---24,270ohm with 2.26v voltage drop

Check it at work before you leave (this is when it acts up)Coolant should be ambient temp as long as you dont start it up.

well i checked that all out i have been between houses and i finally got my tools unpacked anyway everything checked out "A" ok does anyone know if a 2.3 liter will bolt right in i have a 2.5 now with a five speed my buddy has a 2.3 in his truck that he is going to junk and what i am think is to get his motor and put it and the stand and rebuild it from the ground up and then do a transplant his trans is shot it was a 5 speed and so id the trucks computer
( flood) anyway i can get my hands on the motor and i just want to make sure that the thing will bolt up to the tranny and the computer thanks to all again mike

my dad has a 2000 ranger i think with a 2.5 5-speed and it has no power to begin with lol. I used to work at auto zone and they have 2.5L rangers with autos and theyre even slower. But yeah check for fuel problems and vacuum leaks. See if someone you know has an A/F ratio gauge and see if youre running lean.