I drove my truck 3hrs to nj to work.I worked for 5 hrs came back out and now the truck bucks and misses while driving..It seems fine reving it up and the missing comes and goes but is real bad..I changed my plugs and wires a month ago and Im not getting a check engine light...

Ok well I just spend $150 on a fuel pump fuel filter and fuel pump screen and my motherf'n truck got worst..Wtf can this be. filter is on the right direction.

Im getting no cel lights..I even check it with a code reader anyways and nothing..

What else could it be..

I changed plugs and wires about a month ago.,

 

Well it seemed to have cleared up.

 

Maybe you got a bad batch of gas or something? If that is even possible. Post back if it starts again.

 

See I thought that..But I put gas in it 3 times since I went to nj.

 

Another thing, if you haven't done it in a while, is cleaning your throttle body. It really doesnt take long to do and it will help. If you haven't done that yet, that is where I would start at next.

 

I def will..I cleaned the maf this mourning..I think that may have fixed it..The truck has a little over 170k..Thanks

 

Well I was driving again this mourning and it started doing it again..

 

you running a KandN, noticed this before that if the maf sensor gets something on it or starts going for a **** then it starts running weird, reving and missing all over the map, and never threw a code or a light. Somestimes the oil from the KandN causes maf miss reads

 

Nope still have paper filter..It was acting up yesterday and a little bit today.

 

Its on and off..wth can this be.

 

not sure, i havent really had any problem like this with mine yet. Sorry i cant help you more

 

if you can get ahold of a fuel pressure gauge, i would start there. you may have a plugged fuel filter. If you can get ahold of a scan tool to check the mass air flow, should be around 3-5g at idle, and at 2500 should be roughly 40-50g, and at wide open throttle should be about 90g+. hopefully that will give you a starting point.

 

I replaced pump and filter already..I got a check engine light today and was never more happy to see the light come on..Cylinder misfire on #4..What one is that?

 

front driver yo

 

I cant plugs and wires like 2 months ago so im just going to replace that plug and wire.

 

http://ui.abimg.net/images/answers/8...pg?1279560941a

found it

 

Thanks a million..

 

replace the plug and wire, if that doesnt help, look into the fuel injectors.. but I'd recommend looking into the coil pack before the fuel injectors.

 

every 4.0 OHV misfires on 4. ask anyone with a pre-01 ranger. It shouldn't run too bad though. just the occasional miss. seafoam?

 

Injector would make sense.

 

It is pretty bad when it does it..Cuts in and out alot.

 

scrap the coil pack first, check the injectors first, coil pack second.

 

if its missing on cylinder four, it is highly unlikely that is is a coil, cause it would missing on is companion cylinder #3. Def start with plugs and wires.