Ls1 camaro leans out when in PE
 

Hey everyone i have been trying to self tune my camaro and I am running into issues when going into PE. Actual afr is a lot more lean than commanded. I added fuel into the eq ratio for PE with it commanding 11.7 @ 4000 and smooth curve to 7200 commanding 10.88.

While logging a pull the afr is pretty close at 4800 commanding 11.45 and actual 11.68 but as rpm increase to 6200 it leans out 13.7 with a commanded of 11.13.

Can any one help with the reason its not taking the fuel in PE?

SBE ls1
PRC Stage 2.5 heads
TSP tsunami cam
stock intake/ tb
th400 rmvb.

Once I get back to my other computer I will post the tune file.

Thank you in advance.

james.

welp. I didn't save the last adjustment to the ve table for cruising rpm but here is the tune file with the PE settings I am using.

Thank you.

I can’t look at the file I’m on my phone but if it’s not a error in the VE table and you are in speed density. It sounds like your running out of fuel (injector or pump) or possibly both. Log injector duty cycle and check fuel pressure with a gauge. Not just at idle rev it hard. Preferably where you can see the gauge while driving when the lean spot happens

This.

Also OP, why you running it so rich in PE?

Can you post a log?

Well i compared your tune to a stock tune and it makes a little more sense now. Your VE table is stock. You actually need add fuel in the VE table. Don't jack the PE table up to get your "desired" AFR.

Set your desired AFR in the PE table. Then add fuel into the VE table to get your actual AFR to meet your commanded AFR.

Also if it's NA there's absolutely no reason to run it in the low 11's and high 10's.

Also what injectors are in this thing?

Only reason for Pe being so rich was to try and get some fuel in it during the pull. Didn’t seem to add any when the PE ratio was increased.

Yes it is na. I will add some fuel in VE table and do a log.

Injectors are 48lbs injectors. Stock fuel pump.

Here I have attached a log. This has some cruising and a couple of wot pulls.

I put a new fuel pump and filter in to ensure the pump wasn't lacking fuel pressure. It ran a tad better in wot but still no where near commanded.

Thank you everyone for the help.

I don't have a ton of time to go through everything, but from first glance, your numbers don't look too bad, overall. As far as PE commanded, you are still commanding 11's on an N/A car which is pig rich. This does not help power. It actually hurts power because engines actually make more on the leaner side. The reason we add fuel is to keep it safer, so it doesn't blow up from getting too hot inside the cylinder, potentially sparking a pre-ignition if left unchecked. Hot engines make more power, but too hot and they come apart. It's a balance on the physics of it. You can't get pressure without heat, so more heat = more pressure, which = more power. But yeah, no need to run it in the 11's on an N/A car.

Try setting your PE to 1.17, which will command 12.5. You are only 13% "lean" in WOT so just changing this might actually show it's good. The injectors are plenty big according to duty cycle as well which was 48% at the highest, so you don't seem to have a mechanical fueling issue. It's in the tune.

Okay so I took a look at the tune as well. Your VE table looks very stock-ish. You also have DFCO, and EQ tables messing with your numbers. Set EQ ratio to 1.0 above 140* and set DFCO to 284* enable temp. Or look in my sig and watch the guide if you are unsure what I am talking about.

set PE EQ table to 1.151 (12.8:1 AFR)

then use the VE table to meet your target. add or subtract values in relation to appropriate RPM and MAP cells until it meets your target.

don't try and edit WOT with PE EQ table, that's a hack way

True. Hopefully he watched the video but I do think I failed to elaborate into the “why” we tune the VE, to this degree that is lol.

OP: literally every other fueling table other than MAF and VE (which are actually airflow tables) do not increase the actual amount of fuel into the engine. The PCM calculates fuel using airflow values. So, by changing airflow, you in turn change the actual AFR.

When you change the PE EQ or any other fuel table for that matter, you are only changing commanded. PE is one of the only fueling tables we don’t disable and build it into the VE. BE is the other one. Everything else is off so we can get the actual AFR as correct as possible, aka, the VE. We leave PE and BE on because all fuel trims stop when they are active, meaning they must be built into the actual VE table.

I appreciate all the input guys! Chopperdoc I watched your videos and set up the tune and scanner the way you described and it worked a lot better. I only logged around 10 miles of cruising and had to try a wot pull and what do you know fueling was right there. Actually a tad rich on couple areas in higher rpm. I am going to log some more miles and adjust VE Table.

Once that is done I will turn the maf back on see how it goes. I appreciate the help guys.

Dumb question might already covered. But can I just run it with the maf set to fail and not run it? Any downside to leaving it off? This is not a daily or anything. Just a weekend track car.

Really glad to hear that's working better for you. For MAF you can build a table in the scanner, then plot Dynamic Air on the column axis under MAF frequency values from the table, since there is only one row for the MAF table. Provided your VE is pretty good, this will put you in the ball park for tuning the MAF.

VE is what determines the Dynamic Air calculations. MAF uses frequency and a heated element to determine airflow. Both must be tuned, but if you did the VE first and got it close, then your Dynamic Air values are a great starting point for tuning the MAF.

You can leave the MAF fail freq at 0, but you have to log the Mass Airflow Sensor frequency. It will still read that, failed or not. Obviously you'll have to log Dynamic Air too.

Make sure you are using the same units. This is in g/s (grams/second) as pictured. Make sure that your tune is in the SAME units, and copy it directly over. Do not use paste special, just paste the values directly over. Make sure your car is at operating temp too, and all that good stuff, which is the norm for tuning, unless your idle tuning as this log depicts.

https://cimg7.ibsrv.net/gimg/ls1tech...b258925528.png

Alright took the car out to the track finally got a good load on it and was able to go wot through the gears. Still having issues with it not coming close to the commanded afr. I have posted the log and the tune I was going on. First pull it was a lot leaner at wot, added more to the ve and it seemed to help a little but I have values well pass 100. Any help would be greatly appreciated.

1. Pull some timing out
2. Control module voltage shows around 12.9v most of the run