This post is for 5.7 Hemis only as they are equipped with the MDS feature.
I recently installed a DiabloSport tune (CAI 91 and 93 oct) and noticed a brief hesitation between 50 and 70 MPH. Upon some consult with a forum member, we discovered that it appeared that the MDS kicking in was causing this brief, hesitation.
Upon shutting off the MDS with the DiabloSport, the condition stopped.
The following are the steps to shut off the MDS with a DiabloSport Predator Tuner. (U7135)
NOTE: I already have the CAI 91 Oct Tune loaded in the car but I would imagine the steps are the same if you haven't loaded a tune yet.
This takes place while you are in the car with the doors closed and the engine is SHUT OFF and no accessories are on.
Plug in Tuner and allow it to initiate. Follow commands for key on and off, etc.
Select Performance Tune.
Then select Diablo Tunes.
Then select Modify Stock Tunes. (Notice one option is restore: this indicates the CAI 91 Oct is loaded already)
And you have the shift firmness selected. Feels like a spark plug misfire, doesn't it?
This is a long known (February 2008 for me and a couple of others) problem with the Predator. You can get a modified tune from Diablo Sport with the torque management cut back a bit to smooth it out.
Drop Johan Mangs an e-mail at 'johan@diablosport.com' and ask for the modified torque management tune. He'll probably ask you to send your stock tune, and send back both the stock tune and the modified torque management tune. No cost involved.
Thats why I'm back running the stock tune again.
I don't like the MDS jerk and I don't like the way the car runs on when you let off the throttle, it's feels almost like the cruise control is on.
When I do occasionaly run the Diablo tune, I also turn the MDS off.
Scroll down and highlight, then select MDS. It should put an * by MDS.
Here is the important part: after you select MDS, hit the ESC button until you get to the screen that says install tune, then select install. It will go through a process for a bit and then complete and give you a screen that verifies it is done. Then unplug the tuner.
I also just recently reinstalled the CAI 93 Oct tune and it recognized the MDS was off nand asked if I want to reset the parameters. If you want to leave the MDS off, then select "no" and it will keep the MDS off while you change the tune.
Thats why I'm back running the stock tune again.
I don't like the MDS jerk and I don't like the way the car runs on when you let off the throttle, it's feels almost like the cruise control is on.
When I do occasionaly run the Diablo tune, I also turn the MDS off.
I hadn't noticed the running on; I will have to keep an eye out for that. I guess I really like the added power and it seems to shift much smoother, too. That MDS kicking in was too much tho. Very noticeable. I'll say this: if I couldn't turn the MDS off, I would be back on the factory tune!
And you have the shift firmness selected. Feels like a spark plug misfire, doesn't it?
This is a long known (February 2008 for me and a couple of others) problem with the Predator. You can get a modified tune from Diablo Sport with the torque management cut back a bit to smooth it out.
Drop Johan Mangs an e-mail at 'johan@diablosport.com' and ask for the modified torque management tune. He'll probably ask you to send your stock tune, and send back both the stock tune and the modified torque management tune. No cost involved.
Question: should I have the "shift firmness" turned on? I don't think I do, but turning off the MDS eliminated the hesitation....
All I can say is I have not had to turn the MDS off with the Predator, have the shift firmness on firm, and had DS modify the 93 octane tune to eliminate the MDS jerking, and all is well.
All I can say is I have not had to turn the MDS off with the Predator, have the shift firmness on firm, and had DS modify the 93 octane tune to eliminate the MDS jerking, and all is well.
Thanks for the tip. I may shoot and email out and see what my options are!
Hey buddy, it may help but I notice from the photo your predator is reading 9r23b? Is this a custom tune, if not you may need to update to the latest crom from the DS website? The later croms have the smoothing files
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Hey buddy, it may help but I notice from the photo your predator is reading 9r23b? Is this a custom tune, if not you may need to update to the latest crom from the DS website? The later croms have the smoothing files
That does help...This is what was on the DS when I got it about a week ago. Looks like I will need the PC adaptor after all...so, once updated, I should be able to run the cai 93 tune and leave mds on?
Thanks for the tip!
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