I know there are a ton of threads in these forums relating to stalling issues and I have read every last one in 3rd gen ram tech.

Maybe 2 months ago I installed Pacesetter headers on my 2004 QC 5.7. I drove with open headers for maybe 15 miles to an exhaust shop. Less than 5 minutes after leaving my truck stalled and another 2-3 times on the way home. These first few times were only when coming to a stop or slowing down around a corner.

Since then, the issue has escalated to also having RPMs drop to less than 500 while coasting anywhere from 30-50 mph and almost trying to stall. Sometimes, even while at idle, it will surge like it wants to stall but won't. It has stalled in park, while coming to stops, in parking lots at slow speeds, and while turning through intersections. It seems to be a random problem with no obvious signs of reoccurring situations other than those just listed.

Prior to the header install and within the previous year this is what was done:
Throttle body cleaned
EGR replaced
PCV replaced
Regular maintenance
Power Steering Pressure Switch replaced

Since this problem started I have continued with the following:
Transmission filter and fluid change
Spark plugs and wires
Intake manifold gaskets (there was a reasonable amount of oil in the intake)
Diablosport 93 octane tune
AC Compressor Replaced (due to my own screw up)
180 Degree thermostat
Throttle body and Intake Manifold cleaned

I have also checked for vacuum leaks with none found as well as exhaust leaks. I did have a code P0135 (o2 slow response bank 2 sensor 1) come up just a couple days ago. I found 2 small exhaust leaks right next to the header collectors that have been fixed. I cleared the code and it has not come back, but the problem still remains.

The truck has not stalled since I replaced the intake manifold gaskets, but it has been driven very little since then (less than 2 weeks ago). It has surged and tried to stall and has had rpm issues. Additionally it has started to randomly have this problem of pressing the accelerator and the RPMs raising slightly with no response from the truck while at speed. Sometimes it does it and sometimes it responds immediately. There have been no other codes.

I understand there are a couple TSBs regarding a stalling issue, but as this seems to me to be directly related to the header install, I have ignored that as a possibility for the time being as they want to charge me $100 for a flash that I'm not confident will solve the problem. I really don't want to continue throwing money at it while randomly guessing.

The only other thing I can think to mention is that I did log some data earlier today (not that I know anything about what info I should record or how to interpret any of it) to see if there was anything obvious to me that was happening. Out of the 15 minute log, the only thing that stood out to me was when coasting and having the RPMs drop to only a few hundred as if it wanted to stall, both the fuel injector and MAP sensor readings seemed weird to me.

During this period the accelerator pedal was not touched for a total of 15 seconds. The MAP sensor was averaging 1-1.1V for the first 4 seconds, then it started climbing over the next 5 seconds to 2.6V at it's peak and then descended over the next 6 seconds until the gas pedal was touched to 1.6V. At the exact moment the MAP sensor started to rise the "Injector Control Total Working PW" averaged 1500-1700 for the first 4 seconds then suddenly dropped to 650 for less than a second and climbed over the next 3 or so seconds to between 2200 and 2600 for the remaining 8 seconds of coasting. During all other coasting and idle periods during this 15 minute log there was no other issues with the truck and all the readings looked normal to me (if that means anything). I have no idea if this helps in diagnosing anything that might be going on or not, but I thought it was worth mentioning in case it helps.

Sorry for writing a book, but thanks for reading and I hope you guys can help me. If not I have a feeling I might end up grabbing my 12 gauge one of these days and just start shooting at it.

 

i had close to same thing happen on my old jeep and it end up being an O2 sensor which i though that right when i started reading this then i see you mentioned the code you had for the O2 sensor, so i would check and make sure all O2 sensors are connected and if so maybe one is bad and needs replaced

 

I think I'll change out both front o2 sensors for new ones today and cross my fingers. My first thought when this started happening was that it might be one of them. After all, they were the only thing messed with when I did the headers. I made sure they were all plugged in and checked the wires to make sure they are good.

Thanks for the response, I'll update once I swap them out and have a chance to drive it.

 

I had the issue but not near the extent that you describe. I stalled maybe twice in three months and always when putting it in reverse if I didn't give it any gas. I was running a tad lean after the headers coupled with tuner and a few other mods. The 180* thermostat fixed the lean state and it never stalled again, but it would idle down and shutter a bit from time to time, seeming to "catch itself" and bump idle on it's own just prior to stalling.

Grounding my throttle body fixed that as the needle NEVER moves off of 800 rpm now, might be this free or close to free mod will fix you up. Worth a try, anyway...

 

I already tried both of those as you had recommended those in other posts. The grounding seemed to make a difference for the first couple days I had thought, but in the end I think it was just wishful thinking as they symptoms all returned.

The 180 thermostat was done about 3 days after the headers with no noticeable change other than a lower operating temperature.

 

I changed out both front O2 sensors and took the truck for a quick test drive. Overall, the truck did seem to run a bit smoother with slightly more power, but it did not seem to affect my current problems. The RPMs are still fluctuating while coasting as if the computer seem confused. The truck did not stall and seemed to idle fine, but that does not mean it will continue to do so.

What I have noticed since this problem started and did not mention in my previous post because I am not convinced it is an actual problem or if it is normal as I have never before payed attention. The speedometer seems to react too slow when dropping speed. When coming to a stop, the speedometer seems to read faster than I am actually going (not by a huge amount, but a few miles per hour). It takes maybe a second or so when I do stop completely before the needle actually hits 0.

 

I'd reset your computer and re-learn the idle and all the sensors.

I'd also check to make sure your throttlebody gasket is good and not leaking! You can spray starting fluid around the base of it.

 

I reset the computer after I changed out the O2 sensors and before I drove it. The throttle body gasket is brand new less than 2 weeks ago and I have checked to make sure it is sitting flush against the intake manifold.

 

My next guess would be the fuel filter which you will find is non serviceable because it is part of the fuel pump assembly but you can change it if you take the fuel pump assembly out, so maybe you can try that it's easy to do jut time consuming

I just don't understand why it would start after the headers being put on...maybe just a coincidence

And as for the speedo being off not really sure on that

 

I am trying to leave the fuel filter, fuel pump and torque converter as last ditch efforts, due to the expense and difficulty. But if that is the most likely explanation then I can't ignore that. I am crossing my fingers that one of those are not the problem. I am equally confused as to why this all started after installing headers.