Big Bald

iTrader: (1)

As I added mods my stalling has gotten progressively worse. First cams, then the QM 8 Leg and now with the Magnus V5 i can't take it anymore. The issue seems to be mostly on hard turns and When I turn on multiple accessories (lights, defrost, wipers). Which table(s) can help me resolve this. I assume is one of the ISCV tables but my search results only seem to find AC issues and I dont have AC. I thought it was a fuel issues for a while, but I am now sure its one of those tables. Can anyone point me in the right direction?

foxbat

Are you on MAF or MAP?

kaj

iTrader: (60)

You most likely need to adjust your BISS by now. Probably also need have the MAF scalings adjusted. Depending on how big the cams are, that is. You've done a lot of things that are going to mess with airflow. Get those fixed then you should be golden.

Big Bald

iTrader: (1)

i didn't see these replies...sorry about that. I am on Maf at the moment. I have the s2 cams and have adjusted the biss screw blindly. Is there a setting i should monitor when making the adjustment besides RPM? What maf tables would I need to look at?

kaj

iTrader: (60)

You need a tactrix cable, and EvoScan. Then you can log the steps for the IACV and keep adjusting until the trim reaches as close to zero as possible. It's under "ISCV Demand Trim AC off".
Make small adjustments and remember the car takes a min to adjust to the new setting. Make sure your A/C and defrost are off. Also, the reading will change while the cool down fan comes on. I usually wait until I get the same number twice, after the fan has gone off. Usually takes a couple cycles, if I remember right. You should be able to get it to zero with fans off, then it will to change to +/- 0.392 or something like that.

foxbat

I would convert to SD for the peace of mind, as MAF is sensitive to back pressure especially with intake mods. However, I suspect that you might have a faulty stepper motor, those things often go bad at around 60k mileage.

Big Bald

iTrader: (1)

i just replaced the stepper motor thinking that was the culprit as well. Still not luck.

Just so i am clear Kaj......when the car is fully warmed up, that trim is at 13-14. I need to adjust my biss screw until that gets as close to zero as possible? Or do i need to adjust another value to get that trim to zero at idle and at temp?

kaj

iTrader: (60)

13-14?? That is definitely no bueno!

Operating temp, yep! I forgot to add that, sorry. Also, yes: The BISS screw is what you will adjust. A few notes:

*EvoScan will log values in 0.392 increments, if I remember right. So, 0.392, 0.784, 1.176, etc. are the numbers you will see.. or Something like that LOL. You get the idea, though.

*Very important: when the cool-down fan is on, it will read +/-0.392 from the actual value. You will need to wait for the fan to go off, then wait a few (15-30ish) seconds for the value to change again. That will be the actual measurement.

*After making an adjustment, it may take a couple minutes for the value to "settle". I usually wait until the cool-down fan cycles a couple times. Once I see the same value repeat (after the fan is off and the value "settled"), then I make another adjustment.

*If Evoscan shows a positive value, then the IACV is compensating by adding air. In that case, you will need to back out the screw to allow more air in during idle so the IACV isn't adding as much. If the value is negative, then the IACV is compensating by restricting air, so you need to "tighten" the screw down to reduce the amount of air.
I.E.: +0.784 = back out, -0.784 = tighten

*Once you get the value to "0", you will see it change to +/-0.392 or +/-0.784 when the fan comes on. That is normal. But it should return to "0" a few seconds after the fan goes off.

1. Let car get to 180* and take note of the IACV value
2. Make 1/4 turn adjustments until you are within 0.392 to 0.784. Then make 1/8 turn adjustments or less.

That's about it. The only reason I focus so much on when to read the value is because quite a few people weren't told that part and go in circles making changes. I hope that helps. I'm not the best at explaining things LOL

I can make a quick video, if that would help. I'm on vacation, so looking for things to do

Big Bald

iTrader: (1)

i understand perfectly. I assume every time i adjust the biss i have to activate set biss then turn it off and log that value and watch for changes after a few minutes?

kaj

iTrader: (60)

You don't have to activate or turn anything off. I'm not sure what ya mean by that.
just leave EvoScan running and make your adjustments. you will end up with a really long data log ,but the files are super small.