Is the Fuel Rail loss, 23.3 vs 25.0 something I should be concerned about?
This was part of the problem I understood was being chased before I picked up the truck.
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Is the Fuel Rail loss, 23.3 vs 25.0 something I should be concerned about?
This was part of the problem I understood was being chased before I picked up the truck.
1700psi isn't huge. On the log I opened (and forgot to send a pic of before walking away from my PC for the day), there is a big dip of ~5ksi on initial hit meaning when you went WOT and the load came in the truck commanded 25ksi but actually was making roughly 20ksi. That is a dip I would be concerned with and is a decent drop in HP/TQ when that occurs.
How MAF limited does the tune seem to be? Pretty smoky until the boost comes on? The MAF can be tamed down so the fuel comes in more linear and might help with your rail dip, if the tuner knows what he's doing the PIDs can be adjusted as well. Yea less than 2kpsi low on rail isn't a big deal, 23k is stock pressure anyway, but kind of surprised it's low at all being that there's room on the pump as far as amperage goes
I wasn't real sure what was meant by the fuel rail setup, I just assumed it had at least a 200mpa sensor
This is the image I meant to paste earlier. You can see actual rail pressure dips hard at initial load then recovers pretty well. The dip at it's lowest is roughly 22.7ksi with commanded at 26ksi.
My arrows are showing that the truck pretty much recovers. This highlights that the rate at which the ECM responds is what needs some massaging.
My arrows are showing that the truck pretty much recovers. This highlights that the rate at which the ECM responds is what needs some massaging.
It honestly doesn’t smoke much. If I roll into the throttle it smokes very little, even with a heavy foot midway. If I dump my foot to the floor right away, it will puff some smoke but clears up prettt quick.
Appreciate the explanation. As I understand it, there’s essentially a lag between when the pedal goes down to when the pump actually starts sending the desired ksi. This would be massaged by adjusting the response time of the ECM, reducing the delta when coming on.
I’ll keep you all posted when I hear back from UDT concerning his review of the log.
Once you’re squared away, log your lag and post some results here :
www.duramaxdiesels.com
**CHALLENGE** - TURBO LAG TEST using a log
Any one done any of the 3794or 68 stg2 version
www.duramaxdiesels.com
Once you’re squared away, log your lag and post some results here :
**CHALLENGE** - TURBO LAG TEST using a log
Any one done any of the 3794or 68 stg2 version
Ordered a true boost gauge setup so I can log this accurately (0-100 sensor and 5V Dual Universal Input).
@Chevy1925 - I’ve noticed with increased temperatures that I produce more black smoke. To me it makes sense because the air becomes less dense here and therefore messes with the air/fuel ratio of a tune. Is there such a thing as a Hot season tune?
I doubt it affects anything drastically, more curious what others due for the hot dry weather.
Sorry if this question lives elsewhere already. Noticed today that my CTS 3 monitor doesn’t read the proper desired FRP. It limits at 23.5k. Per the auto-cal V3 log, I’m really getting 25.9k as DFRP.
Is this because the ECM doesn’t know the fuel system is capable of more now that it’s not stock? Can I fix the monitor readout to match what the V3 sees?
I’m adding a boost gauge, do I need to also run new DFRP/AFRP wiring to the CTS monitor?
Is this because the ECM doesn’t know the fuel system is capable of more now that it’s not stock? Can I fix the monitor readout to match what the V3 sees?
I’m adding a boost gauge, do I need to also run new DFRP/AFRP wiring to the CTS monitor?
Your device should match. Once rescaled, the CTS3 and your AutoCal V3 are reading the exact same data. I know on my LLY the CTS2 had zero issue reading 29k desired and actual once I updated to the LML rail pressure sensor.
No. If you want to add sensors you will have to purchase Edge's EAS wiring kits. They offer premade versions or universal 0-5V inputs. You would have to add or splice into the rail pressure sensor's harness to add the actual rail pressure reading to your Edge CTS3.
There is no way beyond ECM data you're already reading to get desired rail pressure, it can only come from the ECM data stream.
Appreciate it, I’ll play with how to scale the CTS3.
Sorry I did know the EAS was the only way to add sensors, I’m adding a boost sensor via their 0-100psi adapter this weekend. Was more wondering if I needed a fuel rail adapter for the EAS expandable system. You adequately answered, my CTS3 isn’t scaled correctly so I’ll work on figuring that out.
As far as I know there is not a way to scale the PID that is fed to it from the ECM directly on the CTS3.
Does your log show desired and actual rail pressure above what your CTS3 is saying? If so, you might want to email Edge and see what their recommendation is. I ask this because if it's true, there's something on Edge's side that is being buggy. Your AutoCal and Edge device have access to the same data stream.
Exactly. My V3 read outs show DFRP at 25.9k at WOT, but my edge will only read 23.5k. Actual FRP also doesn’t go over 23.5k (pretty sure, I’ll double check as I was mostly watching my desired) but actual readings in the V3 have been as high at 28k on the highest tune. On the image attached it hits 26.9k
I do have some questions as I’ve been diagnosing tunes and evaluating logs, but I’ll post that tomorrow sometime.
I do have some questions as I’ve been diagnosing tunes and evaluating logs, but I’ll post that tomorrow sometime.
By the way, I did already go into the PID settings within the CTS3 to change the Min/Max parameters…just in case. Max is now set at 30,000, but it still stops reading at 23.5k.
Can you post the log?
I’ll be honest, I’ve never seen this issue before. It sounds like it’s something to do with your Edge device.
Sent from my iPhone using Tapatalk
I’ll be honest, I’ve never seen this issue before. It sounds like it’s something to do with your Edge device.
Sent from my iPhone using Tapatalk
@Bdsankey - I think adjusting the limit within the settings may have been the issue. I didn’t pull a log via the monitor, but on the drive home today I pulled some WOT stints and it is reading 25.9k on the DFRP.
I adjusted the setting while driving before and I’m thinking it didn’t take until it shut-off and rebooted. I’ll keep an eye on it, but when I went into the settings for the PID its min/max was below the thresholds I was trying to monitor.
I adjusted the setting while driving before and I’m thinking it didn’t take until it shut-off and rebooted. I’ll keep an eye on it, but when I went into the settings for the PID its min/max was below the thresholds I was trying to monitor.
Keep us posted! Hopefully that's all it was.