i changed my spark plug wires and fuel filter this weekend but now whenever i accelerate the engine sputters and acts like its gonna die. itll run fine holding any speed, accelerating is the problem. it has no power. i checked the wires and theyre all connected correctly. also now whenever the engine is idling the speed fluctuates a couple hundred rpms which i know it aint supposed to do.

could this be an injector problem? or fuel pump? will a bottle of injector cleaner in the tank be enough to fix it or what?

 

Need more info. Year, model, engine, transmission, miles on engine, miles on spark plugs, brand of plug wires, etc. Did you use dielectric grease when changing the wires?

 

If you removed the Mass Air meter plug did it go back on.
Air tube leak.
Any codes set.
Must get something to start with otherwise recheck all the areas you worked on or was around.

 

Catalytic converter clogged maybe?

 

'02 150
120K
5-spd
plugs are less than a year old
plugs and wires are...duralast...i think. wires are cause that was mid-range on price at autozone

the wires came pre-greased so i didnt use any extra
i didnt disconnect anything other than the wires

development: if i dont floor it i can get decent acceleration but when i start pushing the throttle a bit i am greeted with sputters and knocks and what sounds like misfiring

 

I guess this means he has know idea what motor he has ? He has a 5 speed tho lol.

 

If it has plug wires, it's a V6.

Take that Duralast crap and throw it away. Go get yourself a set of MOTORCRAFT spark plugs, MOTORCRAFT plug wires, and a MOTORCRAFT coil pack. Change them all and I'll bet it runs like a top.

 

Yea, but I wanted him to figure it out, -that way he may remember, (?).

 

i didnt figure the engine size mattered much. therefore no mention of it. yes i have the piece of crap 4.2 v6. the engine that had so much potential but ford decided to waste it.

i did however think that the transmission mattered seeing as the problems vary quite a bit from automatic to manual.

 

You figured wrong, explains why it's broke. Of course it matters, if somethings not working correctly and you want hep fixing it, don't you think it's a good idea to let us know what you have that's broke? How do you expect to get proper help.

It's not a piece of crap, -unless you made it that way. It's a different Ford set up. It's an Essex engine vs a Modular. Once again, explains why it's broke, -the important stuff don't matter to you.

 

youre obviously not here to help so stop talking.

for anyone actually willing to help, lets review.

'02 f150 xl
4.2
5spd
122K
new wires and plugs

severely reduced power during acceleration and rough idle. problem started after replacing wires. ive checked all the wires to make sure theyre on firmly and correctly. i didnt touch anything other than the wires and replaced them one at a time.

 

i told you what you need to do. If you look at my sig, you will see that my truck is almost identical. I am speaking from personal experience - these trucks do NOT like anything but OEM ignition parts.

A word to the wise, don't give Brew a hard time - he knows more about F-150's than you will ever learn in your lifetime. Yes, he's abrasive, but when you bite back he won't give you the time of day.

There is ONE other possibility that comes to mind - clogged cats or some other exhaust restriction.

 

thanks for the info looks like its a little late for the biting back part

next time i have some money ill try changing everything out again. im sure ill be back on this site a lot more cause i really want to learn how to make the best of that 4.2

 

Well, if it was running okay before you changed the wires, there's a good chance you got a bad set of wires or you didn't install them correctly. If you still have the old wires, why not try putting them back on?

You can save some money by buying OEM Motorcraft ignition parts online at rockauto.com.

Motorcraft SP-504 plugs - $3.86 each
Motorcraft WR-6110 wire set - $41.99
Motorcraft DG-532 coil pack - $75.79

I had to replace ALL these at 84k on mine. The coil pack had a crack in it that caused a miss in damp weather. Use dielectric grease at both ends.

 

Hi guys to start out I love my truck it amazing how my truck hasn't been in the shop as many times as my dads Chevy but now I'm having a problem. I have a code lean bank 1 and lean bank 2 I have put new plug wires and plugs (ford parts) I now have poor acceleration it stumbles and backfires. I put a new fuel pump sock and fuel filter in and still have the same trouble. When I change the pump I disconnected the battery and the engine code so far has not come back.