ok so i have a 97 dodge ram 2500 5.9lt 4x4 with 148,xxx miles on it my check engine light keeps coming on everytime i clear it it says random missfire cylinders 3,4,6 always those three. the truck is new to me in the last two months. since i have owned it i have replaced the plugs, wires, cap, rotor, entire exhaust system, exhaust manifold gasket, intake manifold gasket, plenum gasket, valve cover gasket, throttle body gasket, iac, pcv, performed the tsb plug wire rerouting and still after every thing i do it throws the random missfire codes always on 3, 4, 6. now i had it ran through the smog class at school and it passes on gasses but fails for the mil lamp and random missfire. they performed a compression test on my truck and told me those cylinders had low compression. i thought my motor or heads was pretty much toast. i then did more research through alldata and found that the numbers were not showiing bad compression at all they were still in spec just a little low from the others.(sorry to the guy i argued with about the compression you were right the numbers did not indicate low compression issues). this weekend i planon doing a little test with the fuel injectors and swapping 346 out for others clearing the codes going for a drive and seeing if the code comes back showing the same cylinders or differnt ones should tell me iff i just need new fuel injectors on those clinders i also plan on rechecking the gap and routing of the wires and plugs jus t to make sure other than that im at a loss of what to do with it. i need help advice anything my temmp tags expire at the end of this month and i cant get an extension on them so i need the problem fixed asap need to be able to pass smog any help would be great thank you in advance.

 

I thought those compression numbers were good. No worries.

In addition to all the stuff you have planned, and before you swap the injectors around, check for slop in the distributor shaft, inspect the inside of the cap on those three terminals and those opposite them for abnormal wear, turn the engine over with the distributor cap off to see if the rotor wobbles, and turn it over again with the rotor removed to see if the shaft wobbles. Those three cylinders are adjacent to one another in the firing order which makes me suspicious of your distributor's mechanical integrity.

Good luck with the monstrosity!

 

there you go now people wont be intimidated to read your life story. lol

now if those cylinders did have low compression i would think your rings are bad or valve seals.

but im not a professional, i just tinker with my truck as a hobby and someone else will read the correct version of your story and give you some real answers.

 

coil?

 

i was hoping you would read this lol sorry again i was pretty adimit that i had a problem. and i will definitely be looking at the distributer tomorrow wouldnt have thout to look at that thank you.

as for the coil i had thought to check that but wasnt really sure how to all i have to use this weekend is a dmm, basic hand tools and a code reader.

 

No worries.

You're welcome. A wobbly distributor isn't a super common problem, but it does happen every now and then and when it does it can be hard to track down. Usually what you'll see when it happens is terminals in the underside of the cap scored where the rotor has been dragging against them, with the misfires happening on the opposite side of the cap. If you see that, the distributor's a goner.

 

I had the same problem. Ended up that the injector CONNECTORS were missing the little wire clasps that hold the plastic connector SNUG to the injector. If ANY of those are missing, it will be a misfire every time. got new connectors and spliced them...problem solved.

THe PO might have changed injectors, or taken the connectors off. Whenever you take the connectors off, the little thin clasps usually fly off (I know, I have swapped injectors 3 times).

check all your injector connectors and get back with us.

 

ok so good news today checked the distributor no wobble and thank god price was 91 dollars ouch. cap and rotor looked great as they should i had just done them about 2 months ago when i bought the truck.
we cleared all the codes for miss fire i actually unpluged the computer and proceeded to put dielectric grease in every connector i could find under the hood. the truck actually seemed to run better. then we plugged the scanner in and went for a drive waited for all the monitors to run and still had no check engine light.
took it for smog right away and it passed but the engine light came on literaly 5 seconds after they disconnected theyre comp from my truck. code was for random missfire again. but they said oh well it passed and the test was done so you pass.
got back to the garage and noticed a hissing sound from the injector on cylinder number 4 would this be my missfire? can i be loosing compression from the injector oring being bad? and i definitely dont have any metal retainers on my clips where would i find those?

 

you have to have them shipped to home but thats where i got mine when they went flying across the garage.
http://www.autozone.com/autozone/par..._&newYmme=true

 

Just for giggles, get the inch/lbs. torque wrench out and recheck every intake manifold bolt you can reach at 12 ft/lbs.