hey everyone.. i just bought a 96 ranger 4.0L. truck is hesitating when i step on gas from a stop, almost lacking in power. i have changed plugs, wires, cleaned mass air flow sensor, and changed the coil pack... i need some info on what to do next.. maybe 02 sensor? scanners aren't putting out any codes, nor is a check engine light on.. at a complete loss! any help would be greatly appreciated. thanks to all

 

I have a 91 ranger , had sort of the same problem. Try replacing the TPS, or made sure it is pluged in all the way, If you replace it, make sure the new one has steel bushings in the bolt holes, ones without "just all plastic" will give you idle sticking problems. Also when installing leave it slightly loose start the truck let idle come all the way down, then push the TPS to the left or right, the idle should come down slightly, snug it down there( not to tight or might cause idle sticking problems). I know it doesn't look like there's an adjustment, however there is!! TPS should only cost about $24.00. Also you can try cleaning the IAC the tube looking unit with a wire connector to it, its like your carburator, these are about $100.00 new, but you can clean them, use air intake cleaner,( Not carb cleaner), when installing take care snuging bolts, hand tighten evenly first! " I had went to clean mine and snugeg one bolt first then tighten the other, and broke the casting, be careful. Clean air intake with engine running, rev engine a little when spraying, use about 1/2 can of AIR INTAKE CLEANER, (not carb cleaner) carb cleaner removes coating. If this fails replace fuel filter. Hope this helps.

 

I forgot to mention, you should first replace the PCV valve, you will have to do this after you spray out the air intake anyway, because the gunk after spraying the intake will end up on the pcv. hope this helps

 

I'm back again, I forgot to mention something else, I guess the rule of thumb would be , start simple, Check your air filter it may be in bad shape and not allowing enough air in when you hit the pedal. If you can let me know if any of this helped.