We had to upgrade the fuel pump and couldn't find anyone that had one in stock. The new pump is a 255lph to get fuel past 3600rpm. I am starting fresh with the MAF and attached the last file I saved with the proper areas changed. Can I get one of you guys to make sure I have made the correct changes before I load it? Thanks in Advance
Welcome back. Looks like your posted tune is set up correctly for MAF tuning
How have things been. Hope all is well. attached is the scan I did for the MAF and the adjustment has been added to the tune. However, I am still dealing with the same issue I was before the pump upgrade. I can't get past 4k rpm. The motor starts breaking up around 3600 and gets progressively worse to 4000. I thought the pump upgrade would resolve the issue, but I was obviously wrong.
It might seem like bad new but it's actually good news. Your fuel pump is doing it's job now and your extremely rich starting at around 3000 rpm, to the point of your probably washing down your cylinder walls. Just needs to be calibrated again which shouldn't take long.
You can try this tune if you want. I just applied your error % to the MAF curve and smoothed it out
Your VE table is interesting.Originally Posted by 400Horses
Your spark table is interesting.
You PE isnt even there.
your MAF is weird too
If you had a wideband hooked up youd see there was an issue with your fueling on accelration.
I dont know what is done this vehicle and or the engine, but, I'd upload a stock tune back into it.
You have lots of random things changed, this is why im suggesting this.
I didnt even look to see if you had the right info for the njectors, but, I'd start fresh,verify the injector info is correct, then Start tungin the VE table.
Last edited by bk2life; 1 Week Ago at 02:19 PM.
The VE is wrong because it was previously calibrated with low fuel pressure.
Spark tables are almost stock (according to my compare file)
PE settings seem fine to me
There is a wideband in the log
Thanks Rabbs. There has been alot that has taken place with this setup. I am getting a couple of log/VE adjustments in now and with share the changes as I do them.
Here is the 1st scan in SD mode so there is a baseline to compare with after I get a couple more so you can see my progress.
This is the latest scan and corresponding tune after. The breaking up after 3000 has disappeared, and the truck is starting to pull past 4000 as you can see from the scan. Let me know if you see something I have missed. The weak fuel pump I do believe has been the problem all along.
This is the last scan with everything turned back on. There is something weird going on though with the transmission. While we were in SD the truck had the typical aggressive shifting, but nothing strange. When I turned everything back on the trans started acting funny. When driving it shifts fine for both up and down shifts. However, when driving around in 4th gear at around 50-55 My son let of of the gas and it acted like it down shifted to 3rd and the converter maybe stayed locked.... once he gave it gas to accelerate it shifted back to 4th and was fine. Maybe it can be seen in the scan, but I don't really have the tables set for transmission scanning. My main focus is getting the motor tuned now that the fueling issue has been resolved.
Can't tell much about the trans with that log but your fuel trims are still 12-15% rich at low RPM/load. You might want to dial in those areas with STFT+LTFT math on both your MAF and VE.
I didn't think you would be able to see anything, but wanted to put it out there just in case. As for the STFT+LTFT adjustments... The tables you see weren't reading until I enabled the them after doing the SD tuning to fix the rich condition at 3000+ rpm that you mentioned. Why would the tune change so much after getting the VE right using the WB? My WB was reading 13.8-14.2 before I enabled the ST/LTFT's then it all went to crap!
Stoich for gasoline is 14.7 and you tuned it to 13.8 - 14.2 so that's why it's reading rich. Gotta Start using lambda. O2 sensors read in lambda regardless so 1 lambda is stoich no matter what fuel is being burned. That's why it's beneficial to use STFT+LTFT math for everything except PE.
The Stoich for the original base tune from the truck was adjusted and given to me by the engine builder. it was dropped to 14.08 from the 14.7 that is standard. I didn't question it because of the ethanol that is added to pump gas, and I assumed that was the reason for the change. Do you suggest I bump it back up to the 14.68 or should I leave it and tune with the STFT+LTFT?
You can leave the stoich table at 14.1 if you are running 10% ethanol. But when you are actually at the stoich for e10 your wideband will display 14.7 because it?s calibrated to display on 100% gas scale. I use lambda so it doesn?t matter what fuel is in it. The scanner will display in lambda. Even though I?m running e85 my wideband displays 14.7 at a stoich of say 9.6 for my fuel. But since I?m logging in lambda in the hpt scanner it?ll still says lambda of 1.00.
You can leave it at 14.1 if you want, or change it to 14.7. It won't have any effect
So I have done WB VE tuning and I am setting up my STFT+LTFT tune to dial in my low speed. Do I still disable both STFT and LTFT or do I leave the STFT enabled? I have read it being done both ways.
Last edited by 400Horses; 1 Week Ago at 05:41 PM.
If you disable them you won't have any fuel trim data to read? Enable both of them and get a log with as many cells as you can filled in without going into PE.
I'm missing something in my scanner. I have the LTFT + STFT math, Engine Speed( for column axis), and MAP (for Row Axis). Is that wrong?
Make sure your logging all the pids your charting. That should be right graphed right
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