Tire size change oddity and other weird issues

[pjaneiro]

Well, another issue that i realized, and it seems i am not the only one, i think i might of found what the issue might be, ever since i got my pcm tuned, i never was able to get my speedo right, even if i tried the calculator, my gauge would never give me the right speed, and even more weird the pcm would see another speed than the one indicated by the gauge, for as long as i can remember i always thought it was my cluster being too slow, anyways, i got a stock pcm with the stock pcm calibrations for my year 2002 trailblazer with 3.73 gears, i even asked some folk here for a stock file just to be sure, well even there with the stock settings my speed would still not be right, the speed between the pcm and the gauge would have a 5 mph diff, and worst of all if i had my pcm flashed with the new settings for my bigger tires, the pcm would still be off by about 4 mph and the gauge by about 6 mph compared to the pcm, so after going to the dealer getting a routine check, i installed the the stock pcm and asked him if he could do a tires size change for me, he was unsure and let me fiddle around with it, there it was tire size change, and my tire size selection was there, select it saved it and did a test, bam, the gauge needle and pcm read the same speed now, i tested it againg those police radars, right on the spot, so my theory is that efilive does not write to the proper tables on the pcm, i've read numerous post on another forum of people changniog a setting for the po420 and the error still popping up no mather what he disabled, or like me having the program tell you it was written but in fact something went wrong as the tune would not take, my speedo issue is fixed and i got a case relearn doe on my stocker pcm, but now i am worried about having efilive to do my tunes, could someone please tell me if what i'm experiencing is just my imagination, because my numbers don't lie, and my scangauge does not also,

is it because of my OS ? A few members here tried the g1021 setting changed to 25v for the po1481 disabling, on my end nothing, I still get the code if i unhook my magic trick, but some others report it works flawlessly, so what's up with that ?

I'm worried here

[ScarabEpic22]

Ive been helping pjaneiro out with his issues for a little while now and I have an 02 TB with 3.73s as well. Im running OS 12575262 and cal 9351475 and if I change the G1021 setting to +25V and set all the fan params to 0 plus enable the efans option in VATS segment under the platform section I can drive around with my fan clutch unplugged for 30+mins and 6+ restarts without getting any codes at all. Id do it longer but it was stop and go traffic in the summer 90F weather so my temp was rising steadily.

As for the tire calculator, I adjusted mine a little bit in EFILive using my tire params and right now my speedometer and PCM read exactly 1mph slower than my GPS. Ill leave it alone for now, but this is weird your flash isnt taking pjaniero.

I have no experience with the P0420 code, still have my cat intact (for now).

I know you've been fighting this pjaniero, I sure hope we can get this figured out here soon because you've been having many headaches with these issues.

[pjaneiro]

Ive been helping pjaneiro out with his issues for a little while now and I have an 02 TB with 3.73s as well. Im running OS 12575262 and cal 9351475 and if I change the G1021 setting to +25V and set all the fan params to 0 plus enable the efans option in VATS segment under the platform section I can drive around with my fan clutch unplugged for 30+mins and 6+ restarts without getting any codes at all. Id do it longer but it was stop and go traffic in the summer 90F weather so my temp was rising steadily.

As for the tire calculator, I adjusted mine a little bit in EFILive using my tire params and right now my speedometer and PCM read exactly 1mph slower than my GPS. Ill leave it alone for now, but this is weird your flash isnt taking pjaniero.

I have no experience with the P0420 code, still have my cat intact (for now).

I know you've been fighting this pjaniero, I sure hope we can get this figured out here soon because you've been having many headaches with these issues.

LOL, Yeah i know, and I'm really thinkg it's now an OS issue, I had a spare pcm sent to me, it has the same os as my original pcm wich is tuned, for the longest of time i thought it was my speedo gauge being inacurate, but now that the dealer did the tire size change my scangauge and my gauge read the same speed, and it's also the accurate speed, something that i was never able to achieve with the tire size calculator in efilive , i don't use my gps as the speed seems to be 2-3 miles too fast, but i have access to a police radar, and i'm right on target with the change the dealer made, so that's why i think there's some serious issues with efi live and the os version, not all the parameters get saved, the tq management works fine, but i wonder if the ve tables get burned in properly, everytime it get it tuned, engines knocks, pings gets poor mileage, or loss of power...it's agravating, somewhere here there's a fellow having the same issues as i do regarding settings he changes but the pcm still acts as normal (ex the po420)

I'm sure we can get the kinks and bugs out of this once and for all, and get the other options like COT on this thing....

[pjaneiro]

Well , it seems this is an EFI Live issue with this particular os, a friend of mine has hptuners, and even if there's no tire calculator in hptuners for the p10 (this pcm sure needs support)either on efilive or hptuners, at least whenever we change tire size the pcm and needle are at the same speed, also code disabling like p0420 does seem to stick, for the price they sell these things i would at least think that they would test all versions of the os to be sure everything works fine...:doh2:

Little thing i noticed, on the tire size calculator in efilive they refer tables that are not EVEN there to begin with, and if you try to default some settings, sure enough they don't on some tables...

[Blacky]

One thing you could try is to compare the two tunes you have to see which speedo parameters EFILive marks as different.

i.e. read a *.tun file from the PCM when the speedo is wrong and read a *.tun file from the PCM when the speedo is correct, then use EFILive's compare option to compare both files and see which speedo parameters were changed. That will tell you what you need to change in EFILive to achieve the same result.

I'm happy to work with you to sort out any problems. It should not be failing and if it is it needs to be fixed.

P.S. The speedo calculator is not capable of calculating speedo ssetups for ALL GM vehicles. There are so many ways of setting up the speedo that it is virtually impossible to automate the process the same way across all PCMs. For non LS1/LS2 and Diesel vehicles I recommend not using the speedo calculator and just adjusting the speedo parameters manually.

Regards
Paul

[pjaneiro]

One thing you could try is to compare the two tunes you have to see which speedo parameters EFILive marks as different.

i.e. read a *.tun file from the PCM when the speedo is wrong and read a *.tun file from the PCM when the speedo is correct, then use EFILive's compare option to compare both files and see which speedo parameters were changed. That will tell you what you need to change in EFILive to achieve the same result.

I'm happy to work with you to sort out any problems. It should not be failing and if it is it needs to be fixed.

P.S. The speedo calculator is not capable of calculating speedo ssetups for ALL GM vehicles. There are so many ways of setting up the speedo that it is virtually impossible to automate the process the same way across all PCMs. For non LS1/LS2 and Diesel vehicles I recommend not using the speedo calculator and just adjusting the speedo parameters manually.

Regards
Paul


Hello, Thanks for the reply, well that's just it, EFILIVE does not read all those tables, we did a read and one table was changed but that's it, and that's the pcm table, and the numbers there do not match ANYTHING i've ever seen, even the stock file in the repository seems wrong, i used that file in the past, and asked for some other files from other members and get the same results, maybe it's just me i dunno, but i use a scangauge and the speed from the pcm and the speed on the cluster gauge do not match whever i use efilive, but i'm not only having issues with the speedo, i'm also having issues with changes not sticking on the pcm...

[ScarabEpic22]

Weird because I used the speedo calc on my 02 P10 and it got my speedo (both cluster and PCM) closer to the actual mph. I think I was 2-3mph fast and now Im 1mph fast all the time which I like.

[pjaneiro]

Weird because I used the speedo calc on my 02 P10 and it got my speedo (both cluster and PCM) closer to the actual mph. I think I was 2-3mph fast and now Im 1mph fast all the time which I like.

here's my OS: 12587430 ID: AA, Calibration : 9351475


and this is with 2 PCM, the one that i got tuned from Alvin and the one i use as a stocker

the speed indicated is not correct, i need to send in my tuned pcm as i have serious issues with it, ever since my last tune, the thing shifts way too soon on wot, 2200 rpms everytime and never gets passed 3500 rpms, it just won't let me,

[Blacky]

Hello, Thanks for the reply, well that's just it, EFILIVE does not read all those tables, we did a read and one table was changed but that's it, and that's the pcm table, and the numbers there do not match ANYTHING i've ever seen, even the stock file in the repository seems wrong, i used that file in the past, and asked for some other files from other members and get the same results, maybe it's just me i dunno, but i use a scangauge and the speed from the pcm and the speed on the cluster gauge do not match whever i use efilive, but i'm not only having issues with the speedo, i'm also having issues with changes not sticking on the pcm...

It sounds like something strange is happening with your PCM. If you have time to help us track it down could you please provide the following info:

1. A *.tun file read from the PCM when the speedo is reading incorrectly.
2. A *.tun file read from the PCM when the speedo is reading correctly - with no other changes made except the speedo correction.

That way we can see exactly what has changed and try to figure out why EFILive is not picking up those changes.

Regards
Paul

[goldbergv95]

have you ever had your pcm reflashed with the last calibrations?

[pjaneiro]

have you ever had your pcm reflashed with the last calibrations?

After multiple failures, and tests from other members we came to the conclusion that it was eflive program, anything over the han 8 cals from efilive would render the pcm useless, i had it re-flashed by GM to stock and then went to hptuners, thing works great now, and also since hptuners has the settings for the efans, i no longer have my cel come on for the fans, also my p0420 are gone

[skneeland]

After multiple failures, and tests from other members we came to the conclusion that it was eflive program, anything over the han 8 cals from efilive would render the pcm useless, i had it re-flashed by GM to stock and then went to hptuners, thing works great now, and also since hptuners has the settings for the efans, i no longer have my cel come on for the fans, also my p0420 are gone

sad to say, im pretty sure ill be picking up HPtuner for my T.B. too. Is there provisions to put a 2 or 3bar OS for forced induction & also do auto-VE tuning?

[ScarabEpic22]

sad to say, im pretty sure ill be picking up HPtuner for my T.B. too. Is there provisions to put a 2 or 3bar OS for forced induction & also do auto-VE tuning?

Nope, never gonna be a 2/3bar OS for the P10. You can theoretically do AutoVE on the P10 now, just have to be a little creative. I havent done it, but probably will here soon.