Please help with LS1 rich condition

[Finnish Fireball]

Hi guys

Patient under surgery is 1997 Corvette. Stock internals, BBK shorty headers, race cats and Borla exhaust. Procharger P1SC low boost setup.
New Bosch 60lbs injectors #0280158123 and Kenne Bell fuel pump booster. New Injector data was put in PCM by professional tuner and should be correct and in HPT mode. If someone has that data ofcourse it wouldn't hurt to doublecheck. I have no idea who has done this tune, and it was not modified by me other than change the injectors and data.

Car works fine, starts right up, idles smooth etc. but I'm getting DTCs 0132, 0152 and 0172. All pointing towards rich condition after injector change. I did a pressure test and could not find any vacuum leaks. So I took the bull by the horns, purchased MPVI3 and thought to start learning some tuning. I have read about HPT until my eyes hurt, watched videos and what not.

Attached is the tune my car has, and a driving log. STFTs and LTFTs do show it really is rich at cruising? I did reset the LTFT trims before drive, cleared the DTCs but could not get DTCs to reappear today. No SES light now.

What is your suggestion to lean out those rich spots, can I for example just multiply by 0.9 those areas on VE table that the trims show rich? I'm hesitant to start VE tuning and MAF calibration all over from zero since there is no issues how the car behaves and I'm afraid ruining all that I hope baby steps is all we need to keep the codes away and let me pass our yearly sniffer test.

Would be really nice if some of you experts could help a foreigner rookie tuner. Sorry for the long post but I hope it covers all the needed info.

Tero base.hpl
Tero base.hpt

[Alvin]

This looks like it just needs tuning to me.

If the tune is 100% spot on and you change to other injectors with good injector data the car should not be rich or lean.. The problem in this case is that the tune wasn't right to start with.

The injector data is questionable. I think FIC in Georgia has it from Greg Banish. I have my own that I pulled from ford data but you are extrapolating a lot to do that. But those injectors do not have data like a lot of others on the market.

You should look at doing this with a 2 bar OS / 2 bar map sensor etc.

[Finnish Fireball]

Thnx Alvin, I totally agree that a proper dyno tuning with 2 bar stuff would be a killer move, but at this point I just need to lean out that fat area on part throttle 40 - 70 mph cruise without making any damage elsewhere. Dyno and WOT becomes at later stage.

Any other views how I should approach this? Remember this the first time for me even pulling data into HPT so rookie questions may feel stupid to you. I just think it doesn't hurt to ask before trial and error method which I'm very familiar with

[dhoagland]

I belive what Alvin is saying is be 100% sure of your injector data before you start changing your airflow tables.

If everything was correct before the injector swap, meaning fuel trims all good, and now you have issues, its bad injector data.
IF the injector data is spot on, absolutly no doubts, then the tune must have been off before the swap.

FOR COMPARING ONLY:
Here is your tune with the main VE adjusted from your log data, copied from an error log, pasted into your tune file "multiply by % 1/2" then smoothed in.
This is so you can see the results of the changes.
Again I would not suggust this until you are 100% sure of injector data

Also, log MAF HZ so you can check fuel trim error against MAF

[Alvin]

Since this is setup in MAF you would find the spot in the MAF table and lower the numbers to take fuel away.

[horsepowerguru427]

Heres 2 versions of your tune put into either MAF only or SD. Like alvin said, If its running MAF, then log in MAF only and see where youre rich. Youll need to log MAF (frequency) scanner channels so it can be used to plot trims or WB numbers against. MAF freq.jpg The numbers i circled in blue are gather from the column axis of the MAF table in the tune.

This should populate a histogram that will show where youre rich or lean.

[Finnish Fireball]

Thanks everybody for your effort and taking your time helping me. I had already altered the VE a little based on round 1, that was so close to @dhoagland corrections he was kind enough to share so I left that as is. I trust the current injector data btw. The fueling must have been off already with the old injectors, but it did not set the rich codes because injectors were actually a lot smaller than the previous owner thought and what the injector data was there. Thats my thinking.

I made that LTST MAF graph as instructed, hope I got that right? Maf is in use and was not disabled when logging. Reset the LTFT trims, took a ride and thought it already got better based on what I saw in STFT table. What really surprised me was that now the DTCs popped back. So it really is not yet lean enough. That MAF log is over my skills, in a way what to do with that info in conjuction with the ST and LT graphs? Hope you gentlemen can provide your knowledge around that. If you have time and interest to write a test tune based on what we have here, I'd be happy to try it out too. Btw this log was done with my tune, I have not yet loaded horsepowergurus MAF only tune.

In the end of the run I noticed my AC was off and setting it back on raised the idle back were it has been. So that didn't change and is good like that.

Here's the data, what next? Should I write horsepowergurus MAFonly tune into PCM and log MAF with that, or can we adjust something based on this data below?

DTCs.jpg

Tero tune 1.hpt
Terotune1.hpl

[Finnish Fireball]

I had some spare time to take another drive. Took STFT+LTFT from previous and pasted multiply by %/half. Maybe a little bit towards right direction but suprisingly small step? No DTCs now. Hope the MAF graph is usable for you who understand more than me

Tero tune 2.hpt
Terotune2.hpl

[dhoagland]

Yes, load the MAF only Tune and do another log
Add channels: Air-Fuel Ratio Commanded, Dynamic Airflow, Cylinder Airmass, Fuel Trim Cell, Injector Pulse Width (both banks)

You could try this (MAF Adjustments into the MAF only tune that was given to ya)

[Finnish Fireball]

I can do that but I have to ask one more, your Tero tune 1_dh_07_18_25.hpt has this high rpm disable still at 4000 rpm, while horsepowergurus has that at 1 rpm? Is this the field that forces MAF only?

Dynamic.jpg

[Finnish Fireball]

Here we go again, this drive was under 1_dh_07_18_25 except that Dynamic disable High rpm was set to 1rpm, did I mess it?
Added the channels, no DTCs

1_dh_07_18_25Dynamic1rpm.hpl

[dhoagland]

Here we go again, this drive was under 1_dh_07_18_25 except that Dynamic disable High rpm was set to 1rpm, did I mess it?
Added the channels, no DTCs

1_dh_07_18_25Dynamic1rpm.hpl

I believe you got it.
Here it is MAF only (I was taught to set to 400 RPM, I believe that is for cranking and start up purposes)

That last log looked better, hope this will get even closer

[horsepowerguru427]

High RPM disable is the highest RPM it will reference blended air or a mixture of the MAF and VE table. Whatever RPM you set it at, it references MAF only above that. Which is why you set it high when youre tuning the VE table...

Other than that, the only difference in the tune dhoagland posted and the MAF only i posted is his MAF curve is a few percent more lean than mine. However, I made a crude adjustment to the whole table as a guess for a starting point. I believe he used data you logged, which is preferrable.

Also, I smoothed out the VE table on the file i sent. Its not near as rough as what you had to begin with...

[Finnish Fireball]

You guys ROCK! It's nighttime for jacuzzi and couple cold ones here (7PM) We finally have some decent weather. I will log that latest DH tune tomorrow and let's see where it gets us. Big thanx

[Finnish Fireball]

Saturday round #1, yellow Corvette on the one corner HPT on the opposing. This is the log for yesterdays last DH tune.
Are we seeing actual progress, maybe here and there but baby steps.

Tero tune1_ dh 190725MAF ONLY.hpl

Saturday round #2 I tested VE included, got DTC's, round #3 leaned VE a bit and took off some airflow, got DTC's, and then put it back to MAF only for this round #4. MAF only, airflow/HZ a bit less if I got that right DH? and some VE leaning multiply by % half. Heres the log. Starting to feel like I'm chasing my tail, how come after every drive it's showing take off more lol.

Tero tune 3.2MAFONLY.hpl
Tero tune 3.2MAFONLY.hpt

What I noticed when I drove in "normal" mode and the DTC's lit it looks like the major issue was between 3000 - 4500 Hertz, on those areas and 1600 - 2200 rpm or so the trims reguire the most deduction.

Freeze frame terotune3.jpg

[dhoagland]

Just to let you know I'm looking at some things.
Seeing your fuel trims from bank to bank having a pretty big difference from time to time I made a MAF error graph for bank seperated

Tero.jpg

[Finnish Fireball]

I really appreciate your effort sir, take your time, no pressure. According to my searches the high voltage error should be the result of rich condition, since it comes together with system too rich 0172 code. If this doesn't sorten out otherwise then I need to start switching sensors, side to side or a new set. You are correct it is odd that one side is richer. But usually I get the high voltage code for both sides all together. P0132, P0152, P0172 and P0175.

[dhoagland]

Hold up on switching...
I'm throwing some filters in to try and isolate the condition, possibly decel... The filters I had filter out rapid throttle movements, but possibly not enough

[Finnish Fireball]

That decel might be it, I got my PLX wideband display working today and it shows decel really rich no matter what the speed is. I don't have it hooked to HPT and looks like it will never be.

[dhoagland]

That decel might be it, I got my PLX wideband display working today and it shows decel really rich no matter what the speed is. I don't have it hooked to HPT and looks like it will never be.

Yes it is Decel
These are filtered by fuel trim cell, on is decel only, the other is no decel, there is a big difference. Slobbering injectors being exposed by high vacuum??? Completely normal, IDK...
The decel should be filtered for calibration, I believe we all agree with that. However if you look at your logged trims the ECM is definetly adjusting to it and I believe contributing to the fault code. I could be completely out in left field here