6.4l turbo surge

[onebigburb]

Any one have any ideas on why I am seeing turbo surge? See data log. I suspect it is due to some tables for a non existent component? I had a VGT high pressure turbo already wipe out the bearing. I was running rudys 59/72 but now have stocker 52 with 10 blade billet wheel for high pressure as I couldn't source a 59 at the time.

[onebigburb]

Okay, So even if I am only talking to myself at this point I ran a better log and made an adj. to ebp duty limit. What I am not understanding is the ebp tables under egr vs duty cycle limit? The limit from factory tune is 85% but the egr inactive table is 95%. In my brain that says the limit is 85% do not close vgt more then that, but the egr table is 95%. So is my train of thought backwards? Do not open beyond 85%? Honestly what is the point of the duty cycle limit? In my case I am waste gated and I dont see a point in a limit. Let the vane's open as much as they need to meet demand?

[projectlnf]

ok so let me get this straight. your NOT running the VGT turbos right?

[onebigburb]

I am running a vgt high pressure, missing component is egr. I went back to stock size high pressure 52mm, except it is a 10 blade billet wheel and retained the 72mm low pressure from rudys. I guess what is going on here is I am not fully understanding the vgt/ebp tables? If I am correct in my following thinking why does duty cycle limit even matter then?

Here is how I currently understand the tables
-feed forward dc tables = normal operation vgt % that ecu calls out to achieve requested ebp
-duty cycle limit table = max operation of vgt % that actuator can move to achieve requested ebp
-config 0/1 hot/warm/cold table = requested ebp from ecu

[projectlnf]

Is there a proportional, derivative and integral tables in the turbo tab? Sorry I?m not near my computer so I can?t look.

I had this issue on my 6.0 when I swapped strategies.

My proportional was too high and it oscillated. Which sounded like a surge.

[onebigburb]

Not that I see, Turbo has 1 table and I think its proportional? I have attached screen shots of what tables I am seeing and one that I am talking about. These are the only tables that have anything to do with VGT or EBP.

[projectlnf]

second picture is what im talking about. you'll see proportional, derivative and integral. I took a look at the tune and PM'ed you.

[JaegerWrenching]

You are asking for a lot of rail pressure at a low RPM, remember RPM determines HPFPump speed. If you increase both fuel demand and pressure, both of those are asking more of your HPFP. My guess is rail pressure is at play here but it's not on the data log and neither is your mg/stroke or fuel amount,, so it hard to say what's going on. Also don't set the HPFP pressure control valve to 92% leave it at 57%. Setting it to 92 makes the pump think it does something past 57% which it doesn't. This affects your PID fuel pump control loop and can give you wacky issues. TBH I recommend you reset your file back to stock and work one piece of the puzzle at a time to really understand how each piece has its place.

[onebigburb]

I could be wrong I thought rail psi was on there. I will have to look at it again. Thank you for the insight on the 57%. Can I ask why it does nothing beyond this? I have custom fuel setup on the truck. There is no fuel bowl or return regulator any more. After some thought recently I am thinking I maybe having a boost creep problem. After reviewing multipule logs I see I am only making 22psi boost. The tune was fine with larger high pressure turbo. I ordered larger springs for waste gate and plan to install them and see what happens. I had not logged this truck in a long time and have slowly been putting a layout together for it. New layout has fueling side on it I think.lol

[JaegerWrenching]

Sorry i was half asleep when I wrote back last and missed that you had rail on your data log but not desired, and also confused the PCV with the VCV... In your log you can see rail pressure is bouncing around and if you couple that with your not realistic injector PW map you are going to get these type of results. What i mean by not realistic is the shape of that map should resemble a stock map or on a super hot tune it should at maximum flatten out past a certain point. IE: 110mg and 110MPA should stay at a static number from 110MPA-180MPA, but again that should only be done on a kill tune!! If you want a good running truck it should drop with pressure because that's how injectors flow and fuel flow determines potential power output if the air is there. The PCV doesn't need more than 57% to stay shut and the VCV is what controls volume to the pump. Unless you've changed pumps or have a dual fuel setup making changes to them is not required. Take a look at this tune, load it into your truck and see how it runs. You will still need to adjust EBP, Timing, torque to fuel, but I bet it runs a decent bit better. Just know This tune is quite a bit of fuel but i'm hopeful your turbo combo would clean it up and keep EGTs in check. 64_new_pcm_os_delete_250hp_07272023 JW.hpt

[onebigburb]

Thanks JW , I have been slammed lately sorry for delay in response. I will take a look this evening and see where I need to go with it after a log or two. I have one I opened up the vanes and seemed to clear it up quite a bit. Zero smoke and still came on strong. Just a small amount of vgt jumping in that 2000rpm 225lb torque range. When I say small it bumps maybe twice and then lets it rip. I also set waste gate to control on top side. I see in my last log a small opening of the waste gate when just about flat lined. I really went with waste gate to keep EB in check as that is more or less what I am after at this point, getting my ratio down as close to 1:1 as possible. These things are sky high if you ask me stock. I'm toying with idea of going none vgt compounds in s300. It has been done before but blew up on the guy during build. He was keeping with the low A/R though. I think that is a huge problem with these motors/turbos. Need 1.0 or better A/R or EBP spikes IMHO. Again thanks for your time and will report when I get a second to run a log.

[onebigburb]

@ jw, I loaded in that tune an was unable to run it. Truck was surging so bad a 2k rpm 30mph and couldnt even peddle out of it. I loaded back in my air adj. tune for vgt position. I have not posted it up yet. I took a log on your tune but it was with forscan as I cant see egt on hp since a few updates ago. I have a ticket in with hp about not having a pid for the first pre turbo egt sensor. So not sure if you have forscan but I will load up that log. I will load up log and tune for my vgt adj. I then said screw it and added my air to your fuel. No more surge with air. I never leaned on it too hard. Problems I have now are boost will just drop under say 50% throttle on grade and then I have to throttle up to get vgt to close more. Seems I have vanes too far open above 40mph and need to close them back up a bit... Also I am getting a p2263 turbo perfomance pending code. Need to see where I am getting out of balance here. I will load up some logs and tunes tomorrow when I get a chance. I have yet to do a hp log yet as I wanted to keep close eye on egt. Which I never saw over 1000*f have to double check log though.

[JaegerWrenching]

Sounds like you have a bad VGT actuator or your vanes are sticking.

[onebigburb]

well I would Absolutely love if it was a bad actuator. I am not convinced the actuator is bad it is about 2 years old at this point. If it was a bad actuator I would expect a code to be thrown, on my original tune and stock it does not throw any codes. Only on the tune i made to adjust vanes to avoid the surging. I just rebuilt the stock turbo before install with new bearing sets and compressor wheel. Inspected and cleaned vgt which all moved freely then and moves freely when moved by hand now. So any idea on a diagnostic for the vgt actuator? I can't attach forscan logs for some reason must be file ext. So I am posting back your tune with the air from my lastest tune that does not surge. I still need to close up the vanes on this in the higher gears which may take away the p2263. I can run a log with hp now that I know egt will not be out of control.

[onebigburb]

Okay, back at it again today a bit. I was able to tune out vgt jumping for most part and retain my top end boost. Using duty cycle table. However I managed to throw p0234 over boost (green wrench only no MIL). I went over tune and made a small bump in 1 spot seemed off. I had desire of 57ebp and was making 61 ebp which is right on thresehold for that code. What i'm wondering though due to it throwing green wrench and no mil is it due to running FS0P30? Could that be my whole problem? I went from fs0q00 with stacked os to FS0P30.