Yay just another issue... Okay so I did the hughes plenum fix 2 weeks a go and truck has been great running no issues, still runs great but i went in the store the other day came out saw a check engine light. Went to check it and it was a misfire at number 8. I work at a dealership and was able to use there computer there today and still kept misfiring but ran just fine and had power, didn't even seem like it was misfiring. I put in new plugs when i did the fix so thats out of the way.

Things ive tried tonight:

tried a new wire
switched out plugs from another cylinder
did comp test and was at 150
cap and rotor are only 4 months old
checked connections on injector

im lost on where to go from here or what to do to get rid of this darn misfire thanks.

 

What did the plug look like? If it has been misfiring it'll be almost white, as you know...


How's your cat?

 

did look a little white on the top of plug but nothing to get excited about. Idk about cat or even how to check it.

 

Plug shouldn't be white, it's missing. If the cat is clogged it will cause the no. 8 plug to get too hot and misfire or ping. Have you noticed any pinging lately? Have you re-routed your plug wires per the TSB? (it's floating around here somewhere....)

 

Thank you for all the quick replies. But no no pining, no difference in performance at all actually, and idles just fine. TSB?

 

Yeah, technical service bulletin...dealt with the re-routing of spark plug wires to prevent a cylinder no. 8 and 7 miss. Others too, but 7 and 8 were the worst about it IIRC.

Imma see if I can find it for you.

got it:
http://dodgeram.info/tsb/1998/18-48-98.htm

 

Okay thanks, I know the wires are routed right, checked them twice not sure where else to go from here besides go out and buy a cat but really dont wanna drop $100 to find out it doesnt fix the problem

 

If it's original, even if it's not the problem, you'll get a performance boost.

 

Switch your fuel injector with another cylinder and see if the misfire follows it

 

Hmm will have to think about it time to sit down with the ol check book haha. Just some more info for you tho did have a mini fire under bay but fix everything that burned like the vacuum lines. Also when it starts a puff of blue smoke comes out with strong exhaust smell.