I have a 2001 Dodge Ram 1500 4x4, 360 engine with about 126,000 miles on it. About two years ago I stopped driving the truck regularly due to the higher gas prices. I only drove it when I needed to tow my boat or haul something (about once every other month or so).

This spring the truck began to run very rough shortly after starting it up. The truck starts just fine but if you leave it idle for a few minutes it begins to lose RPMs and begins to run really rough. The same occurs if you start it and take off right away. It runs fine for the first few minutes, then begins to back fire, spit/sputter, etc. I can shift it into neutral when this happens and rev the motor all I want, but as soon as I shift it back into drive it runs really rough. The only way to get it to run good is to pump the accelerator and give it a lot of gas (basically floor it).

Once I'm able to do this and "clean out the problem" the truck runs fine, until I shut it off. Upon restart (even warm) it exhibits this exact same behavior. The check engine light does not come on, nor are there any codes to be read.

I talked to my mechanic and he suggested moisture in the gas tank. I treated the gas and even filled it up with premium, etc. That was not the problem.

Recently my mechanic replaced the coil. This appeared to fix the problem for about the first 40 miles or so. But now the truck is doing the exact same thing again.

My questions are:

Anyone else experienced this issue? If so, what was the resolution?

Could it be the coil again? And if so, what would have caused the "good" coil to go "bad" so quickly?

Any there other areas I should ask my mechanic to check out (he's a Chevy mechanic, and doesn't have a lot of experience with Dodge)? I am obviously not a mechanic, nor do I know a lot about engines, etc. so if you reply, please put them in terms I can understand. Thanks in advance for any advice.

 

When my truck did that trick, it was fouled plugs. Replaced the plugs, and it ran MUCH better. I replaced my coil, thinking that was the problem, just like you, with the exact same results.

Other possibilities include a failing O2 sensor..... The sensors on these trucks are heated, so, they start having an influence MUCH sooner than the older vehicles.

What you may want to do, dump some gas treatment (dryer) into it, and drive it damn near empty, then fill up with good gas again. Not sure if it will help at all.... but, sure wouldn't hurt. (even though you apparently have done something similar once already.)

 

Sounds like a failing upstream oxygen sensor to me. If the original hasn't been replaced in 126,000 miles, it's time to do it anyway as they should be replaced at 100,000. I suppose it could be spark plugs as HeyYou suggests -- it's easy enough to look them over.

Usually a failing coil acts up when hot rather than when cold.

Welcome to the forum!

 

when i read your post i thought of the same exact thing, sounds like your 02 sensor has some carbon built up on it, and ur blowing it out. you can replace just that and get one from www.hughesengines.com but it might go out sooner than it should if your plenum is leakin and lettin oil and carbon get bypassed up there and down to the 02 sensor. take a flashlight and look down the throttle body at the intake manifold and see if you see a bunch of burnt of oil or oil pooling in there. My truck would sound like i had a cam in it sometimes right after startin it till i got it warmed up and stuff, but since i did the plenum fix and i did a full up tune up at the same time, coil/rotor,plugs/wires, and the 02 sensor and i put it all back together, and the very first time i started it when it was back together i could tell the idle was stronger, and it hasnt done that cam like idle again. Good hunting.

 

My mechanic found the problem. It turns out the wiring harness that runs to both of the O2 sensors had been rubbing on the frame and shorted out some of the wires. The pre-cat O2 sensor was also bad. The wiring has been fixed, the O2 sensor replaced and the truck is running awesome again!

Thanks to all how posted suggestions.

 

Thanks for the follow-up, and I'm glad you got it figured out!

 

+1..... It's great when we get the info about the fix.

 

I am having the same problem with my Dodge 2000 Ram 1500 4x4, 360 engine with about 136,000 miles on it. So it sound like I should start with the O2 sensor. Tried taking out plugs but the heat shields are giving me problems. Will try to remove them.

 

I'm thinking you should start by reading this! https://dodgeforum.com/forum/2nd-gen...um-thread.html

 

I had the same issue except my truck ran rough when I approached 40 mph. My check engine light was also on. When I changed my O2 sensor the check engine light went off and the problem cleared right up.