Recently bought an '04 Dak QC (4.7L) w/ 64k miles. I've noticed it cuts out or feels like a bit of a miss in the 45-65 mph range, it's pretty consistent & also seems worse on really hot days. If I speed up to 70 or 75, it's not there or at least I don't notice it. Besides the cutting out in the 45-65 mph range it also idles a little rough.

I got the car dealer to address an issue of the rpm's bouncing at cold startup. They replaced the IAC, TPS and cleaned the intake and throttle body. Fixed bouncing issue but not the cut out, which I didn't notice when I bought it. I replaced the plugs last weekend with copper NGK's but the issue remains.

Took the truck to a tranny shop and they believe it to be intake or air/fuel related. They cleaned the top end (again) and valves, seems to idle a little better now, but the cut out is still there. They didn't find a problem with the tranny or codes being thrown when driving. In the write-up they said, "found no data very far out of range, fuel trims bouncing somewhat."

I found a similar thread on a Ram that I replied to, but there wasn't a definitive resolution.

At this point I'm thinking a bad injector (which I plan to test) or coil, but would like to hear some ideas.

Thanks!

 

MMO. cant hurt

 

I'd check 1st for a bad spark-plug-wire.
Check it in the dark. Look for a spark at higher rpm.
Have someone holding the gas pedal at about 1800.
Look real close. Just make sure you and your shirt
stays away from the fan, pulleys and, belt while
doing it.

 

he doesnt have plug wires,he has coil packs on top of the plugs.

 

Correct, no plug wires. Now, instead of replacing a wire set for $40, you can replace a set of coil packs for $150, or $25 each. Suppose it's worth it when everything works correctly.

I have Seafoam in the gas tank now, hasn't done much.