07 5.7 Hemi Consistent throttle issue

[ajay4822]

Hello all,

Hopefully I can get some insight here. Having a super consistent issue with a 07 Grand Cherokee donor hemi, it's swapped into an 02 GC. Went through all the basic troubleshooting and can't quite figure it out, it seems like a computer/tuning issue because it is so consistent. It'll do it every time, in 1st, 2nd, 3rd, reverse, doesn't matter as long as there is a load. It will not do it in P/N.

Any time the throttle is held consistently for about 60 seconds, with the engine under load, the PCM will kill the throttle and trip a sole p2106 code. No accompanying code, I turned off all the EGR, MDS, evap, TIPM comm etc codes. I had to turn the p2106 ON for it to actually show on a scanner. Cycle the key and the throttle comes back again. Tried throttle relearn countless times, metered the 5v supply for the APP/TB, no problems, checked for shorts to ground as well. Swapped a another used TB (unknown if it was truly good) behaved the exact same, same issue. Swapped in a known good APP and still did it. Also swapped in a new replacement PCM, still does it. Most of the sensors are new as well.

I was hoping you guys could look at my config and log and see if there is anything that is not normal and might be why the PCM kills the throttle.

Thanks for the help!

[ajay4822]

throttle fail.hpl
throttle fail2.hpl
hemi updated tune(rev5).hpt
Had some issues uploading, it should be good now

[drumnbasslvr]

Get that mph into the log. Make sure all abs sensors are playing nice and rear gear ratio is set properly with tire size. You don't have any real useful pids in the log. Add more! Total airflow too. Can remove inj pulsewidth, useless. The tune shows it very low anyhow. My experience had me clipped once because of a front abs sensor not working in an 06 300c. We simply need more data from you to help.

[ajay4822]

Thanks for the input, unfortunately since its a swap there is no ABS computer or body control module. I talked to chris at hotwireauto and he said this configuration has worked in the past. The 545rfe has all the sensors it needs to shift and whatnot. I will definitely try and add more channels, any specific ones that should be on there other than total airflow? I am not sure if I can even monitor that since it does not have a MAF.

[ajay4822]

Swapped a brand new Mopar TB on today. Still did it, took another log with more info taken. Let me know what you think.

throttle fail3.hpl

Also after looking at the log I noticed the LTFT's are pretty high when cruising. But disabling the o2 sensors makes it run rich, and still does the throttle kill.
throttle fail4.hpl

[drumnbasslvr]

No there isn't a mafs there, they're simply not used typically. Airflow is a calculated representation. The more you mod, the more it reads incorrectly. Most tuners "lie" to the computer whether purposely or incidentally. HP and TQ numbers skewed and not showing correctly on an srt pages display such as car making 750 to the wheels only shows 350 on the dash display. Your trims aren't horrible, your fuel is likely got an ethanol blend to it or the engine is years old. I did a little homework on your issue just now and reviewed your current log and previous one. May I ask to see misfires current and history in another log? For every cylinder.

These codes sometimes can have weird behavior. We cannot see everything going on inside a pcm or understand every part of its logic. We have quite a bit of control but not all of it. For example, 2007 silverado had an alternator issue where it would slowly back off charging request to 12.7 volts after a startup. Someone changed the alternator. No change. This one wasn't tuned, I got roped into it, I scanned it, +30 on both sides trim wise. Plugged in the vent tube from bank 2 to the intake box, trims cleaned up, and voltage bumped up to 14.4. Another topic is load shedding. Not going to dip into that but it's a real thing I assure you.

Anyway, bring another log showing accelerator pedal voltage, misfires current and history, fuel system status #2, remove skim, and monitor pids. those aren't needed and don't do much ever. Some reports of a mechanical valve train issue causing reversion. Wiped cams are so so common in these engines. Broken valve springs, Lifter failures. Even rocker arms bent. Pushrods being bent doesn't happen often though but still possible. Worth a look. I'm rambling, throwing ideas out there.

Can you scan for transmission codes? Like with another device such as snapon or autel? And any other modules that are scannable?

[ajay4822]

Sounds good, I'll get a log with all the cylinders misfires/app voltage/fuel system 2 status on it. I just rebuilt the motor, has about 200 miles on it so far, on it's third oil change. No metal shavings in its last change, and no noises or ticks when running. I will pull valve covers when I get some time and do a little digging regardless. Trans is rebuilt as well, I figured the HPtuner could pull TCM codes because I did have a couple of issues with the TCM relay not working and it threw codes for that. I was wanting to take it to the dealer and see what they're scanner told them. PCM is the only module, everything has been removed.
Thanks for the input, I really appreciate it!

[ajay4822]

Setup an appointment next week to get it scanned. Attached a few more logs with the updated channels. throttlefail1-5 were all with the rear end jacked up, much faster to T/S, throttlefail1-7 are all street driving. Throttlefail6 has 3 fails and is 50/50 highway/city. throttlefail7 is all city and no throttle failures. Let me know what you guys think.

throttle fail5.hpl
throttle fail6 drive.hpl
throttle nofail7 drive.hpl

After looking at them for a little while I can't really see anything abnormal exactly when it happens. APP sensor % E drops to 0% randomly during cruise, but another known working pedal does the same thing. Also swapped a brand new MOPAR TB on and it still doing it, figured it was worth swapping it out just in case.

[drumnbasslvr]

If you're willing to do team viewer, I could possibly help more. Pm me if you like.

[Dustinmherb]

Ajay, any resolution to this issue? I'm having a similar issue with a HEMI swap where all throttle response goes away after a few minutes on the highway and only restores after engine restart. No issues during city driving.

[LilSick]

post the oem read

the current tune

and a log

[yoecotec]

For anyone having the same issue after a HEMI swap, loss of throttle after a few minutes or while cruising, it is the #2 brake pedal switch that needs to be wired (NC contact) to the PCM.

[PurpleRam]

Thanks for sharing.