02 Silverado Tune Help

[ippielb]

2002 silverado with a 5.3l engine, flex lite electric fan, cold air intake, throttle body spacers, iridium tip plugs, long tube headers, cats removed, 35" tires, 4.56 gears.

I keep burning front 02 sensors, can't seem to stop it.

Exhaust smells rich, and you can mainly always see the humidity from the exhaust like it's cold out.

truck feels gutless in mid range.

Here's my tune, rip it apart, the more you criticize it the better.
15239

[Big Mike]

Are you sure it isn't burning coolant?

[ippielb]

Are you sure it isn't burning coolant?

100% sure it's not coolant. Smells like fuel, doesn't smell sweet, exhaust is dry. It running rich.

Plus it has been doing this for a LONG time, and haven't had the coolant drop at all. Not just a recent thing, i bought a new duramax and have kind of neglected this truck. Just getting back to finish the job.

[BLK02WS6]

Would help if you posted up a log. Also, that is not a valid tune file - not sure what you posted...

[ippielb]

Would help if you posted up a log. Also, that is not a valid tune file - not sure what you posted...

It's a ctz file for putting onto the controller so I can put the tune into my truck without having to use the laptop.

What would you like me to log I will go make one right now.

[BLK02WS6]

Default metric pids would be good. Can ctz files be converted back to .tun files to view on a laptop? I never use them, so don't know...

[ippielb]

I just open up the ctz file on my tune tool, opens right up like a .tun file does. Let me know if you need the .tun file. I will get it from my truck when i get back to the farm. In tractor right now.

[ippielb]

15241\
heres a log i dont know if its what you guys needed.

[BLK02WS6]

Here are the pids in the default metric group (ignore the x's). That is what we need to see. Mainly wanted to see LTFTs, but other things in there too... 15242

[ippielb]

heres the one with defaults pid

15243

Driving it right now seems like it had more balls, maybe it finished it's learn process after the new intake manifold and knock sensors. but still has that dead spot mid range and doesn't like to accelerate unless it has more rpm. Needs a little help on idle. Idles a little low and has the shakes.

Also one other thing, i have the flexalite dual electric fans, it has the variable speed controller on it, i see on my EFI live there is some spots where you can tune in an electric fan like on the new silverado's. Just curious what wiring would need to be changed, is there a kit? I have burned two controllers from flexalite for no apparent reason. I'm ready to keep them on the shelf and use the ECU to determine when the fans come on.

[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.

15280

[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.

[EagleMark]

I know that's a popular belief but the post cat O2 sensors can effect fueling by 10% found in 98-00 Vortec disassembly. Haven't found it yet in LS stuff.. but in a 0411 PCM vehicle I did have one bad cat that threw off same bank fueling and when the post cat O2 were disabled it went away. So I'm guessing the same scenario. The bank with faulty cat post O2 sensor voltage was swinging like a pre cat O2.

You do need to physically disconnect post cat to disable them. Turning off DTC does not disable them. I usually fix them discretely and leave them all plugged in.

I didn't study your data log hard but looked like the big fueling issues were at idle and low RPM. I'd be very curious if you still had post cat O2 hooked up during that log and seeing another log with them disconnected with no other changes!

[ippielb]

I will most definitely go through all the tutorials again, it's been a while since i played with my gas tuning. Got a duramax and been focusing on it lately.

I did not disconnect the post cats 02 sensors in that log, i will keep the same tune on and then unplug them and do another log to see if any changes are made to my fueling.

I agree that fueling issues are at idle and low rpm, you can tell just by sitting in the truck.


Edit:

Looking at the spark for stock vs my tune for low octane, i kept it pretty conservative, but i am going to set the low octane spark table back to stock and see if that changes anything.

[Gregs]

I agree that fueling issues are at idle and low rpm, you can tell just by sitting in the truck.

Looking at the spark for stock vs my tune for low octane, i kept it pretty conservative, but i am going to set the low octane spark table back to stock and see if that changes anything.


yeah its a good idea to keep the low octane stock. Generally you could put in a conservative 3-4* increase across the board on the high octane table without any issues.

first thing i would do if i were you is fix your pe settings then get the maf tuned then you can work on the ve table. keep an eye on your spark advance because in the last log something was taking huge bites out of it. if you log spark EST perimeters it will tell you whats taking the advance out. my guess is either ac spark reduction or torque management. BTW you will probably like the truck a lot more when you reduce/eliminate TM

[ippielb]

yeah its a good idea to keep the low octane stock. Generally you could put in a conservative 3-4* increase across the board on the high octane table without any issues.

first thing i would do if i were you is fix your pe settings then get the maf tuned then you can work on the ve table. keep an eye on your spark advance because in the last log something was taking huge bites out of it. if you log spark EST perimeters it will tell you whats taking the advance out. my guess is either ac spark reduction or torque management. BTW you will probably like the truck a lot more when you reduce/eliminate TM

Set my low octane spark table to stock. Left my high octane table alone, except for smoothing a few rough spots out.

I will change the PE settings, and start tuning my MAF.

I believe the spark advance is being effected by my A/C, for some reason my AC clutch keeps engaging and disengaging randomly without anything changing.

I have removed 80% of torque management as well.

[ippielb]

I updated the firmware and software and it says $050B code is coming up when i try to plug the controller into the truck and do a tune.

[joecar]

Did you update the BBx config files... (Program All)...?

[ippielb]

Got it working, tried to unplug the rear o2 sensors and made an idle log.
15305

Then i put on this tune.
15306

And did a log with that tune for doing VET and MAF
15307

Now i'm going to finish using the log to try and tune a little bit more.

Just cant get this to work right. MAF calibrating is confusing me. The values aren't the same. Cant figure it out.
15309
15308

[ippielb]

15310
Is this acceptable for a VE Table? Or should i smooth it all out?

[joecar]

Got it working, tried to unplug the rear o2 sensors and made an idle log.
15305

Then i put on this tune.
15306

And did a log with that tune for doing VET and MAF
15307

Now i'm going to finish using the log to try and tune a little bit more.

Just cant get this to work right. MAF calibrating is confusing me. The values aren't the same. Cant figure it out.
15309
15308

The first pic you showed is the correction multiplier map (with low cell count filter and transient filter applied).

The second pic is your MAF table, you do paste-multiply-with-labels into this.

Remember that LTFTBEN is only good during CL... outside of CL you have to use WO2BEN.

[joecar]

15310
Is this acceptable for a VE Table? Or should i smooth it all out?I would leave it as is...

I would also look at the cells not hit, and compare them to the general shape of the developing VE and do some manual extrapolation.


How did you arrive at this VE table...?

[joecar]

I tried and it wouldn't open...Bret, you will need a later version of the V7.

[joecar]

...

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

...Just a note regarding lambda-EQR math:

1/0.85 = 1.163

1/1.15 = 0.870

Without a dyno I would aim for EQR 1.16 (lam 0.86).

[joecar]

I will most definitely go through all the tutorials again, it's been a while since i played with my gas tuning. Got a duramax and been focusing on it lately.

I did not disconnect the post cats 02 sensors in that log, i will keep the same tune on and then unplug them and do another log to see if any changes are made to my fueling.

I agree that fueling issues are at idle and low rpm, you can tell just by sitting in the truck.


Edit:

Looking at the spark for stock vs my tune for low octane, i kept it pretty conservative, but i am going to set the low octane spark table back to stock and see if that changes anything.Did you read the Calc.VET thread...?