Question on speed density

[jamesbond2509]

I'm currently running Speed density on a 2002 GMC with a 6.0 engine with that custom operating system. I'm trying to get rid of the PO 102: but I understand the MAF has to fail for speed density to work. Is there any way the P102 can be removed or perhaps I can hook up the map sensor again so that the code does not show up. Any help would be great!

[joecar]

The PCM goes into VE-only mode (i.e. Speed Density) only when it sees a MAF DTC, without it it comtinues to use MAF/VE comination (if MAF is physically absent, PCM calculates what it should be)...

so there is no way to remove the DTC if you want SD.

[joecar]

You should already have a MAP sensor connected.

[joecar]

If you connect the MAF sensor, the DTC should go away.

[joecar]

BTW: 2002 is a Gen III... I'll move this thread to Gen III.

[jamesbond2509]

Hi Joecar - Thank you very much for your reply - So if I connect the MAF and reset the code I can continue to run SD and the MAF Error will go away?


Best Regards,

[jamesbond2509]

Actually I read your earlier post - Looks like I have to run this in MAF/mode temporarily - except I cannot get this thing to idle in this mode??

[LastCall]

If you are referring to the engine light from the P0102 code, you can disable the MIL for the code and it will run in SD mode and still have the MAF failing.

Post your tune and a list of your mods.

[joecar]

You can disable the MIL for P0102 as LastCall said, the DTC will still be present, this causes the PCM to failover to VE-only (i.e. SD).

[jamesbond2509]

Okay so here is the tune that I need to have the P0102 colds not showing. It is a Speed density tune using a custom operating system. I went back to plug in the MAF and it is idling really rough (maybe it is an limp mode)

　

my mods are gen III 6 L engine swap, with LS 9 cam, trick 7675 turbo, intercooler 42 pound injectors, 4L80 swap.

　

Any help here would be appreciated so that I can at least idle and drive the truck for a little bit. Thanks a lot

[LastCall]

Is the code the concern? Or are you trying to run a MAF tune? I would think that turbo would quickly max the MAF range without scaling it.

[jamesbond2509]

I need to run my MAF tune for a day and then flash it back to speed density!

[LastCall]

I need to run my MAF tune for a day and then flash it back to speed density!

Try the tune attached below. I adjusted many of the parameters back to stock, there were some very unusual things in your tune. PE fueling was set to stoich, idle timing tables were very high for such a small cam, injector flow rate should be a flat line (manifold referenced) unless you are not using the factory fuel regulator, etc. Do a compare and you can see the changes I made.

Do you have wideband? Can you go a log of maf freq vs LTFT or Wideband BEN?

Are you on PT.net? Your screen name look familiar.

[joecar]

There were a lot of things different than stock, there's a lot going on there...

as LastCall alluded to, it is best to start from stock and to edit only those tables that need to be.


Try LastCall's tune, and post some logs.

[jamesbond2509]

Hi Silly question - How do I open the .ctz file.

Its been over 12 years on the PT.net forum - seen quite a few mods! And you?

Thanks

[LastCall]

The Ctz format replaced the bin format a few years ago. Sounds like you have an old version of efilive. There should be a "check for updates" in the Help Drop down menu. I would start there. And then check for updates on your BBX/V2 firmware in the eFILive scan and tune application. Those two things should bring you up to date.

Cool. I've been on there about the same amount of time. Since the days of it being a subforum on ls1tech. Time flies.

[joecar]

From V7 tunetool, go File->Open and select the .ctz file.


Or, setup your Windows to associate .ctz with the V7 tunetool, then you can double-click on a .ctz file.