So i have this 1998 ram 2500 5.9L. Every morning when I leave my house COLD engine about 1/2 mile away it acts up. its bucking really bad acting as if your not giving it any gas. pump the gas pedal it sort of helps. cap rotor plugs wires have been replaced. it does that for about 20-40 seconds then its gone until the next morning. im thinking possible TPS anybody had any similar problems.

 

I have the same condition with my 97 2500. I was planning on swapping the parts you mentioned. I only notice the bucking when it has been raining the night or day before I fire her up.

 

which parts the tune up part or tps& iac.

 

plug in a code reader, I am willing to bet O2 sensor or TPS....

 

i own a dodge ram 2500 5.9l having a skipping problem replaced cap, wires,coil,plugs & injector #5 code says cylinder #5 misfireing need help w/problem

 

I plan on starting with tune up parts but will change the the two sensors if I don't notice any improvements.

 

You may want to check for Technical Service Bulletins (TSB's) from alldata and check to see if the injector wiring harness has any issues.... Jeep has similar issues with the same code from bad insulation.. also how many miles, any chance they are clogged and nonresponsive from bad gas?

 

it had a upstream o2 sensor code about 4 months ago cleared it never came back on but when i checked it about 2 weeks ago it had code "upstream o2 sensor low signal voltage" but light never comes on while doing this. tried fuel injector cleaner but who knows if that really works. you know have hand what grade is recommended for a 5.9L have been putting 87. but that shouldnt be the problem because it hasnt always done this

 

mentalmidgit,
Mine does the same. Try and pay attention to see if filling the tank helps. When I get below half a tank it pulls air from the fuel pickup in the tank somewhere and causes a lean miss that gets progresively worse as the tank drops.

 

Well everyone, Rick emailed me asking if I had solved the bucking problem and I had. But you aren't going to like the solution because I didn't. Here is the email I just typed to him. I must warn everyone that this MAY NOT BE THE CAUSE OF YOUR PROBLEM, but it was the cause of mine:

Yes, I found out what the problem was, but I don't know if it will be related to yours.

As my post had stated, I had been having problems for over a year with my engine. Well, back on Aug 1, the engine threw another code at me. Same cylinder (#5). Had it at the shop for a month and finally got together with the shop owner/mechanic. The guy he had working on it was ended up trying to treat the symptom, but not finding the disease. We found the disease and it was a bad one.

Originally, the valve guides on the Drivers side bank were bad, but replacing them didn't help the symptoms. It cured the code, but the engine still ran like dog doo doo. So, we started doing every test under the sun. Injectors, swapping injectors, testing the current to the injectors. No luck. Everything checked out, until he had me remove the rocker arms for that cylinder and apply air pressure to the cylinder. Oh boy, the engine didn't like that one!! It had 0 compression in that cylinder because the pressure was going out the exhaust side, and as it turned out, the intake side as well. Both valves were burnt, or so I thought that was the whole problem, it wasn't.

Sooooo............I ended up pulling the cylinder heads. What I found shocked both me and my mechanic. Both cylinder heads had cracks between the Intake and Exhaust valves. The Number 5 was the worst of all, but the others weren't far behind.

As it turned out, after some work and talking to 4 different machine shops in 2 states, I learned that the heads on the Magnum Series 360's have a manufacturing or design defect. Mopar will not acknowledge it, but they do know about it. If you get a reman crate engine from Mopar, the block will be a reman unit, but the heads will probably be BRAND NEW!!! Tell me if they don't know about the problem!!

So, instead of installing MOPAR heads, I got some aftermarket OEM replacements. They look the same, but I think the valves are slightly larger. Along with checking everything that I learned from here, such as the plenum pan gasket (new one came with the set), I got it all back together.

This engine didn't have this much power when I bought it in 2001 with 80K miles on it. The whole process of replacing the heads, gaskets, and a new double roller timing chain had taken care of more problems that I didn't even know it had.

That's it. Hope this helps. But then again, i don't wish this problem on anyone.

Lance