Picked my ram up today, it runs great through town/cruising ect. If I go to get on the highway or put a load on it like going up hill it starts to shake bad and run rough and not accelerate. If I hit the kickdown shifter it usually happens as well, but if I let off it seems to clear up. I finally got it to throw a code p0305 which is a cylinder 5 missfire. It has new plugs, wires, cap/rotor, Im thinking it could be a vacuum leak since it only happens when I put a load on it? Possibly the MAP line?

 

did you reroute the wire per the TSB? check your cat to see if it's getting ready to take a dump on you.

 

Whats the best way to check the cat? I sprayed wd40 around all the vacuum lines and there was no change in idle so i do not believe its a vacuum leak. It was burning a lot of oil/coolant in the last engine plus this engines coolent temp sensor went so it was dumping gas out the exhaust so maybe the cat is plugged.

 

plenum gasket...

 

and cat........

 

Plenum gasket is new, this engine is not burning any coolant or oil, also it is not acting like the last engine did when the plenum gasket was gone. Im thinking cat as well.

 

I know when it was my plenum I had no lower end power, which would clear out when I stepped on it. This time I have no upper range power.

 

just tap the cat, and see if you hear anything in there thats loose, if so, then its bad

and if you do replace it, replace the 02 Sensor as well

 

So i'm having the exact same issues you've described with my 97 ram. What was causing the code on your truck?

 

I never want to see that code again in my life. Last time I got that code, I thought a valve floated and bent. I took the heads (plural because I figure I should have both checked if I'm doing all that work) off and sent them to the machine shop to be inspected after I found a burnt valve. Both were cracked, and I needed four new valves. This was an extreme case and I highly doubt you would have this problem, I just saw the thread and cringed when I looked at that code.