Hey everybody I'm new to the site and have a problem with my 2000 ram 2500 it has the 5.9 v8. Some days when I start it or if its idling it misses, it also makes this strange knocking sound that seems to come from around the converter but we've checked into the converter and transmission and everything is good there. It had a code come up once that was a misfire on two cylinders but we replaced the spark plugs ( the pickup had been sitting for a couple years and had shot plugs) and that has never bothered or shown up again. the thing that has me stumped is that theres no check engine light or anything, and when the engines under load going down the road or something it runs fine. just misses and makes the weird noise idling or stopped at stop lights. Hoping that somebody might have some answers as to what it could be. I'm thinking try some plug wires and maybe a cap. i've read on here that sometimes a vacuum line can be bad, i wondered if anyone could specify more about that. Hoping for some guidance here, thank you all.

 

i should mention also that the engine had good compression on all cylinders when we tested it.

 

replace the rotor, cap and plug wires.

 

Check the plenum as well. Starting with the above suggestion would be a good idea.

 

alright guys that's what i figured, i'll give it a try and post if it fixes the problem.

 

also check the o2 sensors, TPS and IAC sensors (TPS=throttle position sensor, IAC=idle air control) if it isnt the things above, sounds like the same problem I had and I changed all those things and it turned out to be the O2 sensor pre-cat (sensor 1)

 

hey guys, thought I would let you know i finally got this thing figured out. turns out the guy that owned it before me got cylinders 3 and 6 spark plug wires switched so those two werent even firing, found that out by tracing the wires. also the cap and rotor were shot. running great, getting better MPG's and has twice the power as it did. thanks for the help and advice.

 

Excellent. Funny how trying to turn your eight into a six doesn't work out very well.

 

I had very similar issues with mine. It turned out to be both the I.A.C. and the T.P.S. Being used to old Fords, I was shocked how much a simple sensor could cause such a headache. The I.A.C. has become slow in reacting with thottle and the T.P.S. had one of the small pieces where the sensor connects to the throttle plate shaft had broken clean off. I figure that was the whole problem. So far 3 weeks and counting since and no issues.

 

i once tried the whole V-7 thing, seemed like a good idea, but NOT SO