3.0 Cyl 5 Misfire

[WNY964x4]

i Just bought a 2000 Ranger with the 3.0 Flexfuel , i have changed the plugs wires and coil pack and a code for Clyinder 5 Misfire keeps popping up. I plan on doing a compression check tommorow , in case it is the head what is the cheapest way to fix it , if it is the injector what is the easiest way to change it , by the way the truck has 146,000 miles and we do not have E85 available around her , any replies with tips would be great , thanks

 

[almostclueless]

If the compression in that cylinder is good, consider spending 60 bucks give or take for a diagnosis at a Ford dealer shop. An injector problem could be the injector is just filthy or bad, or it could be a wiring or computer problem.


Ideally you shouldn't have changed the coil until the diagnostic was done, because the problem could be the wiring or computer with it....though if it were bad another cylinder should have indicated misfire too.


All you can easily do is look for a bad plug wire, low compression by comparing all cylinders, or bad spark plug.


BTW, what plugs are in that thing? Number on their side?

 

[WNY964x4]

before i changed the plugs it had a misfire in clyinder 2 also and that went away , i put in bosch platinum plus 2 plugs and napa belden max wires , the coil is a duralast from autozone since i work there , the coil on the truck when i changed it was still the motorcraft one , the cylinder 2 mis did not go away till i changed the coil , it was idiling kinda rough so i cleaned the IAC and that made it a little better but that cyl 5 mis is still there

 

[WNY964x4]

Did the compression check , pushin 100 to 120 psi on cyl's 1-4 and 6 , only readin 40 psi on cylinder 5 , i can get a reman head through autozone , where i work , for 210 plus a 50 core , need opinions on where to go for a new head ?

 

[almostclueless]

I would strongly suggest not throwing money out the window.....I had a 302 that didn't smoke at all, yet the rings allowed so much blowby the dipstick would back out of it's tube a few inches after a hard run.

 

[WNY964x4]

well the next thing i was gonna do is hook up the air line off my conpressor up to the compression check line air fitting and flood it with air to see if i can hear the air coming out anywhere , hopefully that will show if it has a ring leak or a blown piston, if it turns out to be either of those i will prolly go for a 3.3 stroker rebuild and a supercharger if possible. if there is no blowby i hope it is just the valves or something , the truck does havr 146,000 miles on the original motor

 

[Southern3.0]

Before tearing into the motor and throwing money at it you might wanna try swapping the cyl 5 injector with another cylinder and see if the miss follows the injector, if so you found the problem. Best part is its free to do, thats if the plenum gasket dosn't break, even the it only costs a few bucks.

Btw the Bosh plugs are Junk! go with Autolights.

Hers a pic of the Bosh plugs out of my old '02 Ranger with about 10,000 miles on them.

 

[inferno94]

Did the compression check , pushin 100 to 120 psi on cyl's 1-4 and 6 , only readin 40 psi on cylinder 5 , i can get a reman head through autozone , where i work , for 210 plus a 50 core , need opinions on where to go for a new head ?

Not to thread jack but is 120psi compression normal on these motors? I'm used to 4cyls with 180-185 being prime numbers. I'm wondering if its merely the older engines as my '07 3L says it has 9.7:1 pistons in my owners manual therefore higher psi in mine vs the older ones, not that I've done compression tests to an engine that isn't even broken in yet.

 

[pillen140]

two things, for some reason bosch have been good in everything i have put them in, except my ranger! caused a skip! since you work at autozone, they sell the motorcraft ones, buy them! and unless you have an extra $6000, a 3.3L is out of the question, and for the supercharger, $3000 plus labor. and you cant have a stroker with a supercharger, the compression would be too high. "either/or" kind of thing.

 

[WNY964x4]

to pillen , i was going for high compression if i do build it , kind of like a mini pull truck , nothin road legal , and the build i would do myself , i am goin to alfred in the fall fo automotive technology , i will try the motorcraft plugs , but when i looked at the plug out of number 5 cylinder it did not look like it had as muck burn residue on it as the others , all the others had a black ring around the seat , this one still looked new.

 

[WNY964x4]

Not to thread jack but is 120psi compression normal on these motors? I'm used to 4cyls with 180-185 being prime numbers. I'm wondering if its merely the older engines as my '07 3L says it has 9.7:1 pistons in my owners manual therefore higher psi in mine vs the older ones, not that I've done compression tests to an engine that isn't even broken in yet.

100 to 140 is about normal for an older v6 engine , it prolly runs about 160 new , the four cylinders tend to have more compression to make up in power what they lack in size , i have seen 4 cylinders with a normal reading as low as 90 though , it was a toyota , cylinders 1 and 2 read normal at 90 , cylinder 3 had 0 and cylinder 4 had 250 , it was a messed up little motor

 

[pillen140]

to pillen , i was going for high compression if i do build it , kind of like a mini pull truck , nothin road legal , and the build i would do myself , i am goin to alfred in the fall fo automotive technology , i will try the motorcraft plugs , but when i looked at the plug out of number 5 cylinder it did not look like it had as muck burn residue on it as the others , all the others had a black ring around the seat , this one still looked new.

are you sure that the plug was in there tight? make sure the threads were clean, and nothing was preventing it from going in all the way, would give low compression. but since you pressure tested at the spark plug hole, that wouldnt seem to be the problem. you did make sure that the cylinder didnt have a valve open right?

alfred is a good school, i was going to go there my self, but i had a p.o.s. pontiac, and didnt have money to commute or live there at the time!.

 

[WNY964x4]

i switched to the motorcraft finewire platinum plugs and it seemed to help just a little , i think there is just some carbon buildup on one of the valves , at least i hope . knock on wood though i have gone 47 miles since the last time i cleared the computer and i can get it in for a nysi tommorow , hope the light doesn't come on in the ten miles from here to the shop , then i can swap insurance and tags off my 96 on thursday or friday. with the compression test the tool i rented from work had a really messed up adapter for this truck and the hose was bent so it was hard to get it to thread in , so i think it wasn't sealing properly , 40 to me seemed a bit excessively low since the thing is not chugging , it has a slight skip that most of the time isnt even noticeable.

 

[stiluv]

have you tryed a wet compression test? put a cap of oil down the spark plug hole if the compression goes up, its the rings. if it stays the same its the valves or the plug hole thats leaking. i had the same thing in my 99 3l flex fuel. the fuel pump went out and burned a valve. good luck

 

[WNY964x4]

i am going to try the wet test tommorow , my stepdad suggested that to me today , if it turns out that it is not the rings , we have a guy that is willing to put the new head on as long as we buy all the parts and he will charge 25 bucks an hour , i hope it is the head and not the rings