I've seen numerous posts asking if there are problems with MPVI2 /MPVI2+ and JTEC. Some have speculated that maybe they turned off MPVI2 / MPVI2+ when they came out with MPVI3. I contacted HP Tuners today and asked them, they replied they didn't change (or turn off) anything in MVPI2 / MPVI2+. They said, if you have problems, send it to them.
I have been keeping an eye on the forums here RE the JTEC+ tuning... I have a 2002 Dak 4.7 I want to tune, last time I attempted it 2 years ago using the MVPI2+ it erased the ECU and then did nothing. Went thru the debugging with HPT & they collected the info they needed and said I should be good to go. Fast forward 18 months I purchased a new ECU for the truck and have the backup on the bench that I can attempt another flash with.
Question is, with the newer released s/w editor, has there been anyone that your aware of that has been successful with downloads using the mpvi2+ & the JTEC controller?
Both ECUs that I have are set to the correct SN but on a read of the ECU, it does not detect the SN and it needs to be done manually. Is that expected with the JTEC?
I can confirm my MPVI2 works fine using a USB cable. Bluetooth is so dodgy I don't even bother.
When you say serial number do you mean the VIN number? I've ran into a few jtec/+ that wouldn't autodetect. Turned out they didn't have a Vin programmed into them. The PCMs must have been replaced at some point and never had the vin programmed in. My Snapon Solus scanner will program/reprogram Vin numbers on jtecs.
ah yes on SN... meant VIN number.
@putts000 what year vehicle and engine do you have?
My jtec vehicles are
98 Durango 5.2L/44re
69 Charger 5.2L/46re from a 98 Ram
I've tuned and continue to tune a few dozen other jtecs for local people. Just drivers, NA cars, boosted, nitrous. I have a '89 Horizon I've been thinking of swapping in another 5.2L/46re combo and try some twisty turny tracks.
The Jtecs are extremely easy to mod, tune, and retrofit since they can run as a stand alone with the only issue of setting a few codes about no communication with the CTM, ABS, and cluster which means nothing to running the engine and trans. They handle any sort of NA powered cars great. Boost works but has a snag that you loose the altitude compensation. I've got a buddy with a 40ft boat with two dinosaur 318 marine engines we swapped over to jtec fuel injection. Only issue there was getting the Magnum flex plate to bolt in to trigger the crank sensor. After tuning them for a weekend he says they use almost half the fuel, no starting or loading up issues, and he says running one of the 318s at 900rpms with a 200amp alternator to charge the house batteries uses less fuel and is far more quite then the onboard 10kw genset with a 2 cylinder Onan motor.
To be perfect it needs a stand alone baro sensor input, the ability to change 4th, lockup, governor multiplier, and add wide band adjustable stoich control. Hardware wise this is all possible. If anyone on here is good with programming assembly we need to pull the stock rom out of the eprom and see if we can tweak a bit of the logic coding.
We're lucky we got what we got with JTEC from HP Tuners. My tuner who is well known has asked for more parameters be added for JTEC but HPT just ignored him. Still there is a lot of JTEC vehicles out there needing tunes and so forth. Mine was a boosted application in which most likely needed more parameters to be added but HPT looks at JTEC as a dying breed I guess.
We got it running and performing good but the added parameters would have been better. I have never had issues with the HPT interface and the ECM.
Went to the wrecking yard yesterday looking for a few parts for the Dak, no longer needing another ECU it was not on my radar. But... out of curiosity from the last time I went looking for one and EVERY JTEC equipped ECU was already plucked... This was also the case yesterday... every JTEC ecu was gone. What the heck?
Have a set of headers on the bench waiting to go in, pulling down the garage gym to be able to pull it in this week and get it done. Excited to get this done, then the y-pipe and cat+catback. Looking to squeeze as much out of it on stock tuning. (having a 2nd ECU could do the tune and go back to stock as needed).
Any words of wisdom to share? (anyone...) no wideband O2 installed, just monitoring LTFT & it looks like it runs rich in its current state. 70mm TB, airaid intake tube with turning vane installed, 12 hole denso injectors, stock airbox with 2.5" vac controlled exhaust cutout attached
Today I read and wrote to my JTEC Dakota. Everything worked fine. I did get a proxy fail at the start, I synced and it worked fine after that. I did try to read/write without being connected to the internet and it would not work.
Evil your's is a 5.9 right? Which year?
I will go ahead and give mine a shot with the backup ECU, 2002 federal 4.7 jtec
Mine is a 5.9, 2001. Everything worked fine. I have MPVI2, I did have to be connected to the internet and I did sync it. I read, wrote and data logged.Originally Posted by steve05ram360
Roger that thanks.
Had a thought since there is so much doubt on the JTEC tuning & what works, would it make sense to have a thread with the known supported JTEC calibrations? Mine = 56029352AC for example, still untested.
it's a good idea
Did a download attempt today, all good. Changed the idle speed and fan temps and the idle is as expected, fan temp... too cold to see that kick on.
56029352AC tune details 2002 dodge dakota 4.7 AT Fed emission
This is using the latest released version 5.0.4, not the beta version.
Last edited by steve05ram360; 01-19-2024 at 09:24 AM.
i can use the editor on my dakota r/t 5.9... but the scanner doesnt work at all.
2000 Dakota R/T
gt45
42lb
honda map
10psi
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