Acceleration Stumble - 8.0L V10

[sreno2003]

Hello

Working on a 2001 2500 w/ 8.0L stock. Been sitting for a year and I recently have replaced all plugs(3 of which were completely burnt up), cats are straight through with nothing behind them currently, new battery. It's not as often as it was a couple weeks ago but now every so often whether hot or cold accelerating starts to stumble and exhaust pops unless you go WOT or I can slightly back off the throttle a bit and it seems to run smooth? During this time it will also idle a little rough but it all seems to clear up and run fine after getting into it some. First though was fuel pump but to me it seems more electrical, something like TPS since it seems I can back off some and it smooths out? Any thoughts or next tests? No codes either

 

[thestuntboy]

I just went through this with mine. Had to change the O2 sensors and it cleared up. She was acting up for a few weeks before it finally threw a code. disconnect the O2 and see if it behaves.

 

[sreno2003]

I was thinking the same but it happens sometimes during warmup when the O2 sensors aren't contributing yet.

 

[thestuntboy]

I was thinking the same but it happens sometimes during warmup when the O2 sensors aren't contributing yet.

Agreed its not likely at that phase but if you disconnect them you can confirm or deny their involvement (short to close). That was what I did to mine and the difference was immediate, if it wasn't for the code I would have left them that way.

 

[sreno2003]

I'll give it a shot and see what happens. Easy test

 

[dapepper9]

Yeah unplug the upstream 02 connectors and see what it does

 

[sreno2003]

Well, finally got around to testing with O2 sensors unplugged and that was it. Not only did it not hesitate but it ran smoother and stronger! What brand O2 sensors work best for this engine?

 

[thestuntboy]

Part #56041212AE is OEM for both sensors for my 99. 2001 may be different so just my .02 is go to dealer and get them by VIN. I have found in my experience my mid 90 to mid 2000's MOPARs are sensitive to aftermarket sensors and switches and OEM prices (here at least) are actually comparable and no repeats to date.

 

[dapepper9]

Ntk is the usual go to, with avoiding Bosch being the other common suggestion

 

[sreno2003]

Replaced with ntk and she runs great now. Thanks for the help!

 

[iceman117]

I have an 01 5.9L 2500. I had a similar problem, I unplugged the up O2 sensor, it ran great. Time for emissions and I put a Bosch in there, still ran rough after a min or two when the sensor kicked on. After reading I assumed that the kid at Autozone gave me the wrong part. I bought both up and down ntk sensors from a different parts store stuck it in and I'm getting the same issue. What could make the truck run lean/rich when O2 sensor is plugged in, but fine when unplugged if sensor is good?

 

[kmrtnsn]

I’m betting all the ignition coil packs are original and more than one is bad.