2010 GMC 6.2 LTFT issues

[XP800R]

Predator U7194 V-9T15B
2010 GMC 6.2 NHT

I've got 2500 miles on my truck now and have a question on fuel trim that I never ran into with my 07 6.0.

At 500 miles or so I datalogged, ran the program, and came up with a -5. Modified the tune and put on a couple hundred miles and datalogged again with no changes needed. At about 2200 miles I thought I'd run a log for fun and was watching and seeing LTFT's in the -7 range. Ran it through the program and +5 was the result. So now I'm back to 0. 200 miles later I datalogged, ran the program, and it said -4, so now I'm almost back where I was. I will run this a few hundred miles and datalog again... I am aware and know if you watch fuel trim regularly it would be like chasing your tail, but these big swings seem odd.

I'm also doing these logs on the same route, same speed/rpm, close to same temp, and no headwind.

Thanks.

[2sscamaro]

If you did a proper cruise log as per the instructions and the resuslts were a -7 (rich) then modified the tune +5 (going towards lean) you would be at -2 LTFT which is where you want to be. When you refer to "So now I'm back to 0" are you referring to your LTFT setting on the predator tool?

[XP800R]

Thanks for the reply 2sscamaro, but your not quite following my question. I have done this before with my previous truck, so am knowledgeable about how to install, datalog, etc...

So, initially when the truck was new I installed the 91 program since the truck requires 91 octane anyway. Drove for a bit and then datalogged, ran it through DSlogRedux, and came up with a recommended slope change of -5. Ran it several hundred miles and datalogged again, and came up no changes. So I was good to go.

Now about 6 weeks and 2000 miles later I datalogged just for the heck of it. I was watching and saw numbers much richer than 0 to -2. One bank was in the -7 range, the other in the -3 range. I ran DSlogRedux and it recommended +5 on the slope. So that change brought me back to 0 on the slope setting.

Now I ran it another 100 miles or better and datalogged again. DSLogRedux now recommended -4 on the slope, which now has me close to where I was before I datalogged "for the heck of it".

Overall it is telling me to make a slope change, I make the change and run DSLogRedux and it is fine, and then a period of time down the road the truck ECM seems to double the change I made or somehow compensate for the diablo changes. I'm just not sure what is going on.

I know this sounds a bit confusing, but I have had nothing but trouble with this 2010 and just not sure if it is the revision or if the truck is doing something different to compensate for Diablo changes compared to my 2007 6.0 which was a piece of cake to get tuned right with this tool.

[2sscamaro]

Yeh that sure isn't normal. I guess you need to start the process of elimination. You could have a leak somewhere in your intake or exhaust system, have you checked the 02 sensors for correct operation, MAF operation etc. Have you chosen extra parameters while you do your logs, like the o2s, MAF, short term fuel trims, etc? Are you modded at all like an aftermarket MAF or throttle body?

[XP800R]

Nope, no mods to this truck yet other than the Predator. I have about 500 miles now on it with the slope set at -4 and I plan to do a datalog tomorrow to see what it looks like. If it is way negative I won't be happy! One other strange thing I noticed is the left bank is alway approx 5 points richer than the right bank - both stock and with the Predator...

I guess one other thing is I have noticed some pretty severe knocking in the lower gears on WOT runs. I have tried different brands of 91 and it still seems to stay about the same. So not sure what the timing is doing and haven't gone any further with the Predator than trying to set the the fuel trim slope. It only knocks under full throttle from close to a dead stop, and I haven't done many runs like that as I don't want to burn too much rubber off the back tires...

Anyone else with a 2010 6.2 having any problems?

[hcvone]

Nope, no mods to this truck yet other than the Predator. I have about 500 miles now on it with the slope set at -4 and I plan to do a datalog tomorrow to see what it looks like. If it is way negative I won't be happy! One other strange thing I noticed is the left bank is alway approx 5 points richer than the right bank - both stock and with the Predator...

I guess one other thing is I have noticed some pretty severe knocking in the lower gears on WOT runs. I have tried different brands of 91 and it still seems to stay about the same. So not sure what the timing is doing and haven't gone any further with the Predator than trying to set the the fuel trim slope. It only knocks under full throttle from close to a dead stop, and I haven't done many runs like that as I don't want to burn too much rubber off the back tires...

Anyone else with a 2010 6.2 having any problems?

Been having issues with my 6.2 2010 Escalade, poor lower speed driveability, full throttle is fine, great performance no knocking, it was so bad put the stock tune back in and that was so much better in normal driving. Waiting until they get it right.

[XP800R]

Thanks hcvone. I think I may do the same. Lots of issues... I wish someone from Diablo would chime in on this 6.2 issue. I also have lost about 2 mpg over stock. I'm happy with the product as related to my 07 6.0, but not happy with it on my new 6.2.

[mikel]

Thanks hcvone. I think I may do the same. Lots of issues... I wish someone from Diablo would chime in on this 6.2 issue. I also have lost about 2 mpg over stock. I'm happy with the product as related to my 07 6.0, but not happy with it on my new 6.2.

What do the logs say?

[hcvone]

Thanks hcvone. I think I may do the same. Lots of issues... I wish someone from Diablo would chime in on this 6.2 issue. I also have lost about 2 mpg over stock. I'm happy with the product as related to my 07 6.0, but not happy with it on my new 6.2.

Yea I hear you, this is my 6th unit, the first 5 were great, worked perfect, I can tell that no one ever drove a 2010 Escalade with the Predator tune installed or they would be unhappy too.

[mikel]

Thanks hcvone. I think I may do the same. Lots of issues... I wish someone from Diablo would chime in on this 6.2 issue. I also have lost about 2 mpg over stock. I'm happy with the product as related to my 07 6.0, but not happy with it on my new 6.2.

Yea I hear you, this is my 6th unit, the first 5 were great, worked perfect, I can tell that no one ever drove a 2010 Escalade with the Predator tune installed or they would be unhappy too.

Funny you say that, the owner of our company has a 2010 Escalade that his wife uses as a daily driver, it has been tuned since the day we released 2010 support, she seems to love it.

Post up your last tune written and original backup please.

[hcvone]

Thanks hcvone. I think I may do the same. Lots of issues... I wish someone from Diablo would chime in on this 6.2 issue. I also have lost about 2 mpg over stock. I'm happy with the product as related to my 07 6.0, but not happy with it on my new 6.2.

Yea I hear you, this is my 6th unit, the first 5 were great, worked perfect, I can tell that no one ever drove a 2010 Escalade with the Predator tune installed or they would be unhappy too.

Funny you say that, the owner of our company has a 2010 Escalade that his wife uses as a daily driver, it has been tuned since the day we released 2010 support, she seems to love it.

Post up your last tune written and original backup please.

I am sending this to our shop to respond to his contact, because he was told and I was there that they (Predator) told him that they did not have a 2010 Escalade to try the tune on, and if it worked from day one how come the extended crank problem that many 10' had, and when contacted there was no fix that Predator could offer? There are many people on this site that have driveability issues at low speeds with their 2010's. I push your products on the forums I moderate and have been very pleased until this one.

[mikel]

The extended crank issue has been resolved for several weeks in the latest revisions.

[toothpick]

Extended crank fixed.....um maybe. Each time I have used my device, the first crank ALWAYS has an extended crank condition. I've got a 09 Silverado 4.8L no other mods, never exhibited the condition until AFTER using the DS Predator. I haven't made a fuss about it, but you can't say fixed if there are still issues with even some. Maybe it's not the same issue, but it certainly seems to be, as far as the extended crank issue goes.......Just sayin.

Yes it's got the latest, no I didn't do it myself, yes I'm the first and only owner, yes the dealer flashed the device before selling it to me....Not trying to start a flame session but I think it's something that should be noted.

[mikel]

Can you confirm for me what revision is on the tool?

[toothpick]

Mine, mine is revision 15....