02 Silverado Tune Help

[ScarabEpic22]

Unless the .ctz is locked, just open it in/with V7.5.

Whats your AFR read during a log? WBO2 working correctly? Without cats, it will smell richer than normal simply because you dont have them performing the reaction.

[BLK02WS6]

Unless the .ctz is locked, just open it in/with V7.5.

I tried and it wouldn't open...

[ScarabEpic22]

I tried and it wouldn't open...

Interesting, worked just fine for me last night...

[EagleMark]

Opens for me?

Looks like a lot of work to Main VE table and some changes to MAF. But B120 is set to 400 RPM so it's running off MAF only? Trims at idle range up to 11.xx%

Mid range power seems to be going into PE and AFR drops to 11.xx and Eq ratio at 1.33?

[Gregs]

initial tune observations:
-you only have like 1* difference between high and low spark tables...better change that to like 4*
-B3618 is set way to rich for my liking try something like .85 lambda (=12.5 afr on gasoline)

log observations:
-it looks like you have not modified your torque reduction tables. your advance is going from like 27.5 to -8.5!!! (reference to frame 1958 in the log.
-you have some wild fuel trims here and there. You have your tune set to all maf so you may want to fine tune that a little more.

i think your problems are that you're running it too rich, and the spark reduction isn't helping. You can remove 80% of torque reduction without any problems. I personally have run without torque reduction for the past 3 years and i haven't had any issues.

[BLK02WS6]

Well, for some reason, when I try to open the ctz file, it tries to open with 7.5.1 build 15 (which I didn't think was even still installed on my laptop). When I open my 7.5.7 build 230 and then open the file it opens fine... go figure... I'll try to look at things tomorrow now that I figured out my issue with opening it...

[ippielb]

Opens for me?

Looks like a lot of work to Main VE table and some changes to MAF. But B120 is set to 400 RPM so it's running off MAF only? Trims at idle range up to 11.xx%

Mid range power seems to be going into PE and AFR drops to 11.xx and Eq ratio at 1.33?

I was researching on how to tune out the cats so it doesn't try to auto correct with the rear 02 sensors for fuel and changing B120 to 400 was one of the recommendations.

I understand what your saying, but how would one go into trying to correct the problems.

initial tune observations:
-you only have like 1* difference between high and low spark tables...better change that to like 4*
-B3618 is set way to rich for my liking try something like .85 lambda (=12.5 afr on gasoline)

log observations:
-it looks like you have not modified your torque reduction tables. your advance is going from like 27.5 to -8.5!!! (reference to frame 1958 in the log.
-you have some wild fuel trims here and there. You have your tune set to all maf so you may want to fine tune that a little more.

i think your problems are that you're running it too rich, and the spark reduction isn't helping. You can remove 80% of torque reduction without any problems. I personally have run without torque reduction for the past 3 years and i haven't had any issues.

I have changed the spark tables as to your suggestion, adding 3 degrees throughout the table.
B3618 has been changed "0-1200" to 0.85 Lambda, and i smoothed "1600-3200" to 0.83 Lambda

I am willing to try new things, if i can change it from all MAF, i will change it so it runs smoother, which RPM should i set it to on B0120, i have set it back to stock for now, 4000rpm. I will try my changed setting right now and see how it is at idle, i have to be getting to work right now so i will check back later tonight to see what other recommendations you guys have.


Here's what i have now.

02 Silverado june 5 tune.ctz

[EagleMark]

It looked like you spark tables both had 3 degrees added to lower end, this is why he saw only 1 degree difference? Both High and Low wer modified from stock. So double check you did not add 6 now! Maybe go back to stock tables or at least use compare to see where you are.

The PE modifier table... have to be careful what your preferences are set to and if you change need to close tune tool and re open to see changes.
Could be Eq ratio which you'd shoot for 1.15
or
Lambda which you'd shoot for .85

B0120 set to 400 RPM uses just MAF and used for tuning MAF, which you need some more MAF tune with fuel trims hitting 11+% in spots. Set to 4000 RPM it uses combo of MAF and VE till 4000 RPM then MAF only.

Not sure where or why setting to 400RPM has anything to do with Post Cat O2 sensor removal? Looks like your DTC for post cat O2 are disabled, but the sensors them selves also have to be removed or not plugged in if there are no CATs.

[ippielb]

Yes that's what I did with spark, i thought it looked A little advanced a bit, it's been a while since i touched it. i am going to go back to stock table for low octane and keep my previous light timing change for the high octane. I never had a chance to put the tune on the truck so that's a good thing.

I will double check my PE table and do a log to make sure everything is where it should be.

I honestly haven't done my MAF table since I made other changes so I will go back and re-do them as well.

So when I take off the rear o2 sensors DTC I can just unplug them and they won't send any data to change fueling? It won't change anything else? I have been trying to figure out this for years I that's true. I will take a set of my old o2 sensors and cut the wires off to plug the holes!

[Gregs]

So when I take off the rear o2 sensors DTC I can just unplug them and they won't send any data to change fueling? It won't change anything else?

the fronts do the fueling, rears are only there to set the dtc light. i recommend reading through the tuning tutorial again as a refresher based on some of your questions.