Anybody want to look at my tune and log? 03 silverado z71

[mvvette97]

Been fighting this truck since I got it last year with the tune. It was terrible in the positive trims and just done very poor on power and mileage. I had made 4 or 5 tunes trying to get it dialed in even used one that had the variable injector table rather than the flat table. It would be pretty good for a while but then would change. Was chasing my tail if I had one. Finally yesterday it threw a MAF code P0101. Went and got a new used maf and put on it and started over with the stock tune with the flat injector table. It was still lean so all I changed was the maf tables and the trims dialed in perfect plus they seem much more stable than the other tunes. Seems really good to me. My wideband is also showing 12.8 when in pe mode so that's pretty good as well. Only mods are long tube headers and ORY pipe and full exhaust. Just wondering if somebody can look at the tune and log and see if there is anything else I can do as far as adding some timing or something to make it any better. It runs great but am all for a bit more power if I'm leaving any on the table. Oh and don't mind the rich idle trims at the end of the log at idle, I tweaked the maf just a little in the idle area and now it idles in the -1 range.

[Gregs]

I've been out of the game for a while but I reinstalled Efilive to look at your file. Looks like you got torque reduction and desired shift times taken care of. Looks like you haven’t zeroed out TCS spark retard and B6607 though. Most everything else looks pretty close to original. I know there are different trains of thought, I’ve always matched B3601 to the fuel type I’m using, I know WeathermanShawn didn't like doing that. Either way works but leaving B3601 stock means you'll bake you're VE/MAF tables in... splitting hairs here. Timing doesn't look too aggressive, are you running 87-89 octane? If you want to play around even more you could do the lean cruise patch and play around with that stuff. B3618 is richer than I run. I typically run 12.8 and lean out to 13.1 in some places, but everyone does things a little different.

I'll be honest I only looked at the tune, haven't got the scanner working right in Linux yet

[mvvette97]

Thanks for the reply. The B3601 I left because I run the 10% ethanol since that's mostly all we have here now. What do you mean by bake the ve and maf tables in? Will this be a problem? Oh and 87 octane is about as good as it gets here. On table B3618 I know I am commanding 12.4 but my wideband is reading 12.8 so I figured that was good. Seems I have always had trouble getting the actual afr to meet the commanded. I just adjusted the commanded to get the actual afr on the wideband at full throttle.. As for timing all I did was add 2 degrees to the timing tables and left it at that. I have very little knock retard so I wonder if I could bump it up just a little more?
I've been out of the game for a while but I reinstalled Efilive to look at your file. Looks like you got torque reduction and desired shift times taken care of. Looks like you haven’t zeroed out TCS spark retard and B6607 though. Most everything else looks pretty close to original. I know there are different trains of thought, I’ve always matched B3601 to the fuel type I’m using, I know WeathermanShawn didn't like doing that. Either way works but leaving B3601 stock means you'll bake you're VE/MAF tables in... splitting hairs here. Timing doesn't look too aggressive, are you running 87-89 octane? If you want to play around even more you could do the lean cruise patch and play around with that stuff. B3618 is richer than I run. I typically run 12.8 and lean out to 13.1 in some places, but everyone does things a little different.

I'll be honest I only looked at the tune, haven't got the scanner working right in Linux yet

[joecar]

You should run at least 91 octane gas due to compression ratio... is this not available to you...?

[joecar]

Is this a truck... do you have a manifold referenced FPR...?

Can you check that rail pressure is constant (with reference hose temporarily removed) at 58 psi...

and then if you apply vacuum to the FPR reference (using a hand-held vacuum pump which has a vac gauge), each 2 inHg vacuum equates to rail pressure dropping 1 psi... can you check this (must have fuel pump running to do this).

Also make sure FPR is not ruptured (is there any gasoline inside the reference hose...?).

[mvvette97]

yea this is an 03 silverado 5.3. As for fuel I have to drive 20 miles just to get anything other than 87 octane. I haven't checked the hose to see if there is any gas in it yet. Didn't think about that. I did drive it 60 miles today and was very happy to see my mileage. I filled up before I left and then filled when I got back and it was getting just between 20 and 21 mpg. not bad for a 4x4 extended cab truck with mud tires on it, haha. I will check the fuel pressure just so I know for sure but I really think that maf was messing everything up. I was always chasing the fuel trims till I was blue in the face then it finally threw a maf code. Changed the maf and dialed in the trims and I have never seen the trims as steady as they are now.
Is this a truck... do you have a manifold referenced FPR...?

Can you check that rail pressure is constant (with reference hose temporarily removed) at 58 psi...

and then if you apply vacuum to the FPR reference (using a hand-held vacuum pump which has a vac gauge), each 2 inHg vacuum equates to rail pressure dropping 1 psi... can you check this (must have fuel pump running to do this).

Also make sure FPR is not ruptured (is there any gasoline inside the reference hose...?).

[Gregs]

Your B3601 is stoich for non ethanol which means your ve table has a constant error applied to it.
10% ethanol should be 14.08
"Seems I have always had trouble getting the actual afr to meet the commanded" VE/MAP not calibrated correctly

On the wideband... are you capturing the wideband as an AFR or Lambda? If you are doing it as AFR you could be getting additional errors if your wideband thinks stoich is 14.68.





Thanks for the reply. The B3601 I left because I run the 10% ethanol since that's mostly all we have here now. What do you mean by bake the ve and maf tables in? Will this be a problem? Oh and 87 octane is about as good as it gets here. On table B3618 I know I am commanding 12.4 but my wideband is reading 12.8 so I figured that was good. Seems I have always had trouble getting the actual afr to meet the commanded. I just adjusted the commanded to get the actual afr on the wideband at full throttle.. As for timing all I did was add 2 degrees to the timing tables and left it at that. I have very little knock retard so I wonder if I could bump it up just a little more?

[joecar]

+1 on what Gregs said about Lambda vs AFR... and on setting B3601 for your fuel (altho most times the LTFT's should be able to handle the difference between E00 and E10-E15.

Yep, it looks like VE/MAF have the error you see tuned in (possibly due to stoich AFR differences in commanded and measured), so commanded and measured won't match.

tuning is much easier with lambda and/or EQR (which is 1/lambda).

[mvvette97]

Hmm, I didn't even mess with B3601. it was set to 14.68 stock