i have a 95 ranger 2.3 with over 200k. ---The truck is missing out...it started gradual and got worse. Plugs should be good and wires as well. I swapped out with some used motorcraft wires and it got way worse.Swapped them back out.I only have the issue when there is a strain on the engine.I checked fire and it seems hot(sitting still obvioulsy). Thought about throwing money at new coils since its over 200k but no use buying what i dont need.---Is there a reliable test for a coil? If i have to buy coils....stock or h.o aftermarket?
With 2 plugs per cylinder i cant believe they would ever miss out.

also every since i had this truck(90k) i have noticed the fire from the coils are "rapid fire".....its almost a continuous stream of fire instead of the normal...zap.......zap.......zap......its zapzapzap....if that makes sense. the truck seemed to run fine before so i never worried about it although i always thought it was odd.

 

somewhere, somehow i got 2 wires crossed. I must have done it when i changed out the wires in the first place.Now i am back at square one....which now doesnt seem so bad lol.

i still have some sort of problem at low rpms.Its not really missing out just a sluggish feel that "seems" like a weak spark situation....but dunno fer sure, thats me guessin.

Is one side a wasted spark or does it change everytime? If so what side?

 

Just a 'may not do nothing but won't cost anything thought':

Try sparking (heh heh) it up in the dark - see if you get a light show anywhere under the hood (eg: coil)

 

ya know, im gonna do that.Planned on doing it the last couple early mornings but didnt seem that big of deal when youre still in a warm bed. thanks for the reminder.

edit--did it but no light show. I did notice that if i rev it hard and let off quickly the rpms will drop to around 450 rpm (guess) and it will stumble at idle for a few seconds until it smooths out.(normal 750- 800 etc) Gonna replace the front o2 sensor as it has never been replaced in 200k miles.Dunno if that is my issue but cant hurt.Might not be a spark problem at all....
does anyone know what side the "wasted" spark is on...or if it has a side? knowing that will help me develop some more hair brain theories lol

 

I agree, don't throw parts at a perceived problem, do a proper trouble shoot then proceed. Do you have a CEL lit???? If so, most autoparts stores will scan the computer for trouble codes at no charge, so post All code Numbers, as they can provide good trouble shooting clues.

If you have, or can come by a scantool that'll read PID's, have a look at the O2 sensors PID output switching speed & voltage range to the computer. Their switching speed slows with age & seeing as how you have over 200K on them I agree they probably belong on your suspect list.

Are you up to date on All past & present due scheduled maintenance items, like filters & the specified plugs & wires????

 

no cel.
i dont know what pid is but i would be interested in learning how to check o2 sensors.---i will look into that.
all maintenance....well all basic shadetree maintenance is done. The truck is not a complete basket case or anything. I would take it across the state without hesitation...now that i got the wires uncrossed ha.
The truck has always been a slow pig but its just really blah in the lower rpm 's

 

Raise the hood in the dark, with engine running spray wires and coils with windex. Let's see what happens.

 

PID = Parameter IDentification, some folks prefer to refer to it as Parameter Identification Data, as it refers to the signal that sensors send to the computer about whatever their monitoring. In your case your interested in what your aged O2 sensors are telling the computer about O2 content in the exhaust & how well & how fast their sending that data, as it directly affects how fast & well the computer responds to fuel injector squirt time & thus keeping fuel trim as close to the stoichiometric 14.7:1 air to fuel ratio as it can. So as this can affect how well the engine responds to throttle up commands & mpg, it directly affects driveability.

A scantool that'll read live O2 sensor PID's at the in cabin diagnostic scantool plug is the fastest, easiest & safest way to measure O2 sensor output. It can also be done by back probing the O2 sensors output lead with a multimeter probe.

Seeing as how O2 sensors switching speed & range slows by the time they have 75-100K miles & most folks change them around that time frame & your O2 sensors have lived what amouts to about two life times, they probably belong high up on your replacement suspect list!!!!

 

PAW PAW--this truck was just getting broke in at 75k i still have another 100k to go ...unless i stumble on a really good deal.

I think this time since the miles are so high i am just going to replace the o2 sensor. If by some chance its working properly i doubt it will be working properly for long. I wouldnt really lose the full price just a portion of it...I would like to get a scan tool though but i dont want to get something outdated or can only be used on volvos or something.-----------on ebay there mostly scan tool obd 2 for 50-75 bucks. Some seem a little different. -----Can you recomend something to me(qualities/brand etc or are they all pretty much the same?

 

Here is one of my posts on a recent discussion about scantools that may answer some of your questions.
Ford Truck Enthusiasts Forums - View Single Post - code reader recommendation

 

changed out the front o2 sensor(rear was recently changed already) and it pulls like it use to now.The worse part was always in low 4th and it completely smoothed out. I still have a problem of it stumbling if you rev it high and then get off of it quick..........in real world driving its not really a problem except sometimes when im pulling into a parking spot. I think i am going to take the air idle thing and clean it. I am pretty sure that will clear all my issues up.-------------thanks everyone.

 

OK, sounds like that was a good move.

Disconnect the Battery B- cable to wipe the corrupt KAM, so the computer can begin to build new fuel trim table with the new O2 sensor & see how it goes.