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I'm working on getting my VE table dialed in. I followed chopperdocs guide on how to set up the tune and have done a couple drives now. Things are going well, but I'm running into two weird issues.
1: Im going lean as i move into around 4k rpm and up, above 40kpa on the map sensor. Where this lands on the VE table is putting me over 100 in terms of the values. Is this normal/okay? My understanding was that this is the computers model of how much air is entering the engine (and with it still being stock displacement and N/A, it shouldn't be able to exceed that, right?)
2: following the guide, I disabled long term fuel trims, AND set the min ect to 284, as well as setting the closed loop enable to 284 as well. Yet I'm still seeing 4-5% in the scanner for long term trims on both sides. Is it actually still adding 4% fuel or is there just some weird bug?
Edit: Here is the most recent tune and the log following those changes
Last edited by HappySalesman; Jul 13, 2024 at 10:12 AM.
You have to manually reset the long term trims with the scanner controls to get rid of them. Otherwise, you are left with whatever was there before you set the tune to quit updating them.
edit-- If you are seeing numbers that high on your VE table, odds are your fuel injector data is incorrect, whether due to fuel pressure or just wrong data. Or you are just running out of pump or injector.
You have to manually reset the long term trims with the scanner controls to get rid of them. Otherwise, you are left with whatever was there before you set the tune to quit updating them.
edit-- If you are seeing numbers that high on your VE table, odds are your fuel injector data is incorrect, whether due to fuel pressure or just wrong data. Or you are just running out of pump or injector.
Ohhh. I thought they would have reset when i flashed the tune.
I'm running FIC 440cc injectors, in the log I posted they were at 10ms at 5600 rpm, so well within range for duty cycle. In previous logs when I was getting the MAF dialed in I was showing 12.5ms at 6500 (and WOT) which is only 75% duty cycle. The data is good as well, straight from FIC.
It's possible the fuel pump is struggling, it's still the stock unit (with a racetronix hotwire kit) but I haven't run into any issues with it before. If you have any recommendations on an electronic fuel pressure sensor I can hook up to hptuners I'd appreciate it.
It doesn't look like it's failing the MAF in the log.
Have you veriied it's giving you a p0101, 102, 103
In part of the tune you are telling it to use just the MAF(High RPM disable is set to 500), in the diag section you have it to fail at 0hz.
Set the high RPM disable to 8000.
Everything else looks right.
Well expect for the VE table, make sure the MAF is failed correctly, put the stock table back in it and start over, that **** is jacked.
I know someone mentioned VE is an abrutary number, yes to an extent. However, an engine does not make power or consume air in the way your table looks.
"IF" the MAF is failed correctly and your VE looks like that, it's either bad injector data or fuel pressure.
It doesn't look like it's failing the MAF in the log.
Have you veriied it's giving you a p0101, 102, 103
In part of the tune you are telling it to use just the MAF(High RPM disable is set to 500), in the diag section you have it to fail at 0hz.
Set the high RPM disable to 8000.
Everything else looks right.
Well expect for the VE table, make sure the MAF is failed correctly, put the stock table back in it and start over, that **** is jacked.
I know someone mentioned VE is an abrutary number, yes to an extent. However, an engine does not make power or consume air in the way your table looks.
"IF" the MAF is failed correctly and your VE looks like that, it's either bad injector data or fuel pressure.
I fixed the dynamic airflow setting in the tune. I'm not sure how much of a difference that made, but I verified I am getting a P0102 and 103, no 101 for some reason. I unplugged the MAF as well, just to be sure.
I drove it one more time on the tune I edited last night (i'll post that and the following log) and it looks like it's able to reach the desired AFR at WOT (I know it's still going lean above 6k, but I think that's because I haven't had a lot of data to input there yet).
I'll post the injector data I have. Having never done it before and without any real instruction, I wont say I didn't potentially get something wrong when copying the data. If someone notices something I missed, I'd really appreciate it.
One last thing I want to check. I noticed looking through logs that even at 3/4 throttle, my MAP is showing 95kPa. When I installed the intake I did relocate the MAP to the front of the intake. Could I be getting incorrect readings because the car thinks it's at WOT (in terms of manifold vacuum) when it's only at 75%?
You are definitely running lean at wot. Fix that in the VE table.
Why did you turn off STFT's ? That's the easiest way to tune the ve table at lower rpm's and probably more accurate than your wideband.
Pic of your log and eq error table. Lotsa red
You are definitely running lean at wot. Fix that in the VE table.
Why did you turn off STFT's ? That's the easiest way to tune the ve table at lower rpm's and probably more accurate than your wideband.
Pic of your log and eq error table. Lotsa red
what filters (if any) are you using in the table? That's drastically different from how mine looks.
No filters.
In the table, at 6400rpm, you are commanding .87 lambda. Wideband reads .98 lambda---that's about 12%. table shows 13.7, but there is a lot more info in that one cell that we can't see.
I know it's running open loop, but does it have 02 sensors?
If so, log them. I use them as a sanity check for the WB02. If the WB is showing lean, and the stock 02 sensors are showing lean also, I'm inclined to believe the WB02.
However, if the WB is showing lean and both 02 sensors are 900mv+, then there's an issue.
I know it's running open loop, but does it have 02 sensors?
If so, log them. I use them as a sanity check for the WB02. If the WB is showing lean, and the stock 02 sensors are showing lean also, I'm inclined to believe the WB02.
However, if the WB is showing lean and both 02 sensors are 900mv+, then there's an issue.
I thought I had added them in my last log, must have missed it (I'll add them in though).
Got my fp sensor delivered yesterday. Getting it set up in a temporary fashion and hopefully can get a couple logs this weekend. The more research i do the more i wouldn't be surprised if the pump is struggling to keep up (or maybe I have a filter issue?)
So it is definitely looking like the fuel pump is out. Weather and timing has been uncooperative, but I got a chance to take it out for a quick rip at lunch today, and it doesn't look good. I'm not sure what filtering to use in the charts, but it looks like pressure is dropping into the 48-49psi range at around 5500rpm and up. I changed the fuel filter just because I figured it was a cheap part and it was probably close to due for it anyway. Now to figure out which pump I should run.
S................................................. Now to figure out which pump I should run.
.
/
So far I am happy with my AEM340 # 50-1200
Inexpensive, easy to mount, has a CHECK valve, and maintains rail pressure for quick start-up, unlike some (Walbro)
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Ve tuning questions 
