I travel once a week on the highway to my cabin about 100 miles away,about a month ago 08 ranger with a 4.0 engine,the truck started bucking and missing when slowly accelerating from 60 to 70 mph,sometimes it bucks real good then I can go 2 weeks without it doing any bucking, I have Changed plugs,airfilter,fuel filter and cleaned the maf sensor,seems weird that it is very sporadic about when it does this, could it be the plug wires?truck has 80 thousand miles,thanks for any suggestions

 

sounds like the ignition coil pack is starting to fail

what make of ignition wires did you replace

 

Going to put ford wires then try it next wknd and report back.though it doesn't do it all the time one trip it is perfect then maybe next time it misses

 

if you are going to put OE type of ignition wires on , install these


these are the best wires you can buy

Granatelli Motor Sports MPG Plus Spark Plug Wires 36-1617MPG - Free Shipping on Orders Over $99 at Summit Racing

 

Changed plug wires today and will try it out later in the week,if this does not cure the problem are aftermarket coil packs any good?

 

i am currently using the screamin demon coil pack

it is definately an upgrade to the factory coil pack

 

Changed wires ,then coil pack same thing,could it be camshaft position sensor? Where is this sensor located?I don't get a check engine light so would this show up on obd2 reader?

 

i have been reading up on these crappy installed bosch oxygen sensors .

it turns out that the check engine light will only illuminate when the o2 sensor heater fails

the oxygen sensor itself may stop sending data to the ECM al together , then the computer defaults to maximum injector firing duration

it would also cause pre-ignition as well as mis fires

the bosch oxygen sensors are easily damaged by any form of moisture in the exhaust flow

so i am having my bosch sensors replaced on monday with the following NTK sensors

NTK upstream sensors 22524

NTK catalytic sensors 22520

these are low band width sensors

 

Well here is an update I put a can of seafoam in the tank and just did about 60 highway miles and it seems to be getting worse,funny thing is idling I'd drive the engine couldn't be any smoother ,just misses of the line for a second and on the highway

 

from the articles i have been reading , it definately sounds like failing oxygen sensors

 

Would there not be a cel then?

 

the ECM will only illuminate the check engine light if the heaters inside the oxygen sensor fail

stupid as it sounds , one would think that computer would issue the check engine light when the sensors stop transmitting data to the ECM , but that is not the case

 

Thanks cheese man ,by the way where I'd the camshaft sensor located ?

 

back of engine under the plastic intake plenum ( manifold ) so i have read about

 

So cel came on code p0300 random missfire,if I go to the stealership will they be able to pinpoint the missfire without putting all kinds of new parts on it if they are going to trial and error I might as well

 

what brand and octane level of fuel have you been burning in the engine

mis fires some times are caused by pieces of carbon in the combustion chamber , sometimes near the spark plug , they prevent electrical arcs from spreading outward

electrical arcs are needed inside the chamber in order for the complete combustion of the fuel air mixture

have the dealership use a scan tool to monitor the oxygen sensor activity , i suspect they have failed or are near failure