Hey everyone,

Just sold my F150 and bought an 01 Dodge Ram 1500, 5.9 L. I love this truck. I bought it at a dealership for a great price. I talked the guy down $3200 to $9350. It looks great and has had only one owner. The only thing is that it has 124000 miles on it. Im use to older trucks and this is the newest truck I've had (...23 yrs college student). The truck runs well but I get a misfire in the #4 cylinder. After I reset the codes it will go away for a couple of days until it happens again. I did a search on the subject and found that it could be a number of problems. The cat, injector, plugs, wires, coil, or compression. My plan is to get a new cap and rotor, plugs this weekened and switch the injector to another cylinder. I also would like to find a shop to test my cat for free. All this will narrow things down, but I would appreciatethe input of past experiences.

 

NO NO NO!!! You're throwing money at the problem and NOT diagnosing the problem.

Examine the plug FIRST. If the plug looks good, then swap it with a plug on another cylinder. Then, examine the routing of the plug wires and insure they are run correctly per the TSB. After that, I would check out the inlet side of the injector to insure it is not clogged.

DO NOT buy a new cap and rotor unless you examine them and determine if they are in need of replacing.

Have the cat pressure tested as well.

Do these one at a time, each time the misfire occurs trying something else. By doing everything at once, you don't know what the actual problem was.

 

thats good advice, I will do what you said. You mentioned the TSB. What is this, the manufacturers suggested specs? Where can I find a book?

 

TSB = Technical Service Bulletin. This is it. Print it out for future reference. I did!

 

https://dodgeforum.com/m_340929/tm.htm
aka Merry Christmas Thread
Check out this link for a downloadable factory service manual.
WC[sm=welcomesign.gif]

 

welcome to df...

yeah make sure you verify parts are bad before swapping them out. no sense throwing money at a truck you just bought. I would also suggest ohming out the plug wire on that cylinder, should not be greater than 12k~15k depending on how cheep a wire it is. If you have a bad wire, you can always get one from dodge or get a set... I'm partial to the MSD 8.5 superconductors (~40 ohms/ft). If you get plugs, autolite 3923's are the way to go (standard plugs, non-platnum)... if you need a cap & rotor... get them from dodge as well, from experience they seem to hold up the best compared to the others I've tried (accell included)

 

I bought the Mopar performane cap and rotor set. It was only a few dollars more than the std replacement and seems to be of better quality.

 

how did the old ones look?

 

yea check the spark plug gaps, i also had misfireing in y number 5 and 7 cylinders turns out all my plugs were way off gaping, that salved my problems