VE Table not changing AFR

[Jeffgiroc]

So I have had no success in getting my changes to the primary VE table to actually take affect and change the AFR readings I'm getting on my wideband. Every time I copy and paste the AFR error values to the VE table the AFR readings never change when i do a run with the scanner. I'm pretty sure i have set up the speed density tune file correctly but no matter what i do to the ve table I can't get the AFR to lean out. I've tried every little thing I can find in the forums but nothing seems to work. I'm using a tune file i got from the people who installed the instigator cam in the 5.7 ls1 that I put in my 86 IROC. I've made a couple of changes to the idle airflow and to the injector minimum pulse width, and it up for speed density. Otherwise it's what I got from the shop. I'm new to all of this so any advice would be greatly appreciated.

[gametech]

In order to help you need to list a rundown of what parts you are using and post a datalog. For some reason you have MAP values for something other than a 1 bar sensor, and your VE table is completely jacked up right now.

[2xLS1]

Put it back in closed loop and tune it with the fuel trims (part throttle) and use the WB for WOT tuning. And you zeroed out 2 injector tables. Put those back to stock.

[Jeffgiroc]

This is a similar tune to the one i posted before and this one had no effect on anything as well. This is also the data log that i did with this tune. It was an obnoxious lap around the neighborhood with a lot of crackling and popping with low to mid throttle in first and second gear, but when i was hard on the throttle it was a little better and when it hit about 3200 rpm it instantly cleaned up and took off like a rocket. The kapa units that the MAP is reading is just how it was set up originally I have never changed anything on that, I don't know why its reading that instead of in bar. The engine is a 5.7 ls1 out of a 2001 z28 Camaro, it has an instigator cam with duration of 240 intake 244 exhaust @.050, lobe lift of .3580 intake .3510 exhaust and lsa of 112. I have long tube stainless headers and 3" flowmaster system behind it. Stock fuel injectors. Again I appreciate any help yall can provide. I know this thing is all out of whack and everything I've tried after watching tons of videos and reading tons of posts just simply isn't working.

[toonwarrior]

How was the spark timing tables derived?

[Jeffgiroc]

I haven?t touched the spark tables myself. They were done by the shop I bought the engine from when they put in the cam. They made the original tune file to go with the cam and it hasn?t worked very well.

[abc]

So I have had no success in getting my changes to the primary VE table to actually take affect and change the AFR readings I'm getting on my wideband. Every time I copy and paste the AFR error values to the VE table the AFR readings never change when i do a run with the scanner. I'm pretty sure i have set up the speed density tune file correctly but no matter what i do to the ve table I can't get the AFR to lean out. I've tried every little thing I can find in the forums but nothing seems to work. I'm using a tune file i got from the people who installed the instigator cam in the 5.7 ls1 that I put in my 86 IROC. I've made a couple of changes to the idle airflow and to the injector minimum pulse width, and it up for speed density. Otherwise it's what I got from the shop. I'm new to all of this so any advice would be greatly appreciated.

Log the NBO2's and adjust the VE table based on their error for part throttle drivability. Right now your just way too rich most everywhere based on the WBO2. You say your changes don't seem to have any effect, how far are you changing it? Looks to me as if you need to go 15 to 20% leaner in most areas. While adjusting, remember to smooth the area of the VE table your working in. As a test to confirm your changes take effect, subtract 20% from the VE table starting at 1200 rpm and above. Show us a log of a short drive with low to moderate throttle application.

Your gonna need to make a decision on injectors soon if your gonna keep rising in the RPM. Looks like you may run out of injector.


Do you still

[Jeffgiroc]

Thanks for the response abc. Unfortunately I?ve already tried what you suggested about using the nbo2 to dial in the low throttle areas and there was zero change after modifying the VE table. I?ve even gone as far as reducing the entire table by 50% just to try and get some response but there was nothing. I feel like there is some setting buried in the tune file somewhere that?s screwing everything up but I just can?t seem to find it. I hear you on the injectors, this car is just for some weekend fun and I?m not racing it or anything so I figure I might be ok sticking with stock but if I have to replace them I will.

[gametech]

Going back to my first response, now that I see a datalog I can say for sure that your MAP sensor does NOT correspond to the linear and offset data in your tune. Find the part number on your MAP sensor and put the correct (most likely 1bar) values in place of the random 2.5bar data that is in there now.

[Jeffgiroc]

So there are two numbers on the MAP sensor 12614970 and 71241. I?m not sure which one is the actual part number. Also I don?t know how to go about finding and entering the proper information you?re talking about for the map sensor. Is there a tutorial somewhere I can check out on how to do that? I don?t want to waste too much of your time. I apologize for my ignorance on all of this stuff this is my first engine swap project.

[gametech]

That 12614970 part number is a standard ls1 1bar MAP sensor. I believe the correct linear and offset are 94.43 and 10.33, but you should look up a stock ls1 file in the tune repository to double check those numbers. In your tune look under the engine>airflow tabs and on the left side of the screen you will see where these values are. Be aware that having the correct values put in for one of the most important sensors for airflow calculation will completely change how your tune runs (if it runs at all after all the changes you have been chasing). You will likely have to start completely over.

[Jeffgiroc]

Ok I?ll give that a try. I certainly dont mind starting over on the tuning process if I?m able to get this thing running right. Do you think that this could be the source of the issues Im having with not seeing any response from changing the VE table?

[gametech]

I don't know what other issues you may encounter, but correct MAP values are one of the core bases of everything in the tune. This will change where you land in your spark tables as well as the VE table. But yes, this is definitely part of the problem with your changes not working properly.

[Jeffgiroc]

Wow what a gigantic difference! You were clearly right about the MAP sensor it changed everything drastically. It's clear that I'm going to have to start from scratch with a stock tune file in order to get this this sorted out just like you said. now its running too lean and banging out of the exhaust before it dies. Thank you for your help on this gametech I really appreciate it.

[gametech]

Wow what a gigantic difference! You were clearly right about the MAP sensor it changed everything drastically. It's clear that I'm going to have to start from scratch with a stock tune file in order to get this this sorted out just like you said. now its running too lean and banging out of the exhaust before it dies. Thank you for your help on this gametech I really appreciate it.

Glad I could help. For future reference, if you ever get a tune file from someone else, use the compare feature in HPT to judge it against a stock file. You would be surprised by how many random changes some people make. Sometimes this is to match a different part they were using, sometimes accidental, and sometimes just ignorance. Either way, it might very well be some huge background problem that you otherwise would not notice.

edit-- The people who gave you the tune may very well have been using a 2.5bar map sensor they had laying around, and completely forgot about it before giving you that file.

[abc]

Ya, the MAP reference being that far off was probably keeping it in PE most of the time and therefore you were not seeing the changes via the VE table.