That's what is killing me about all this. Where is it pulling the extra timing from? If you look at the idle log, it's even worse...Originally Posted by Kill
That's what is killing me about all this. Where is it pulling the extra timing from? If you look at the idle log, it's even worse...
What year is your truck?
2005
I have individual IAT and ECT modifier tables for Pilot Quantity, but not for Pilot Timing.
So with the values you have in those tables and the point you picked in your log. Actual pilot timing should be roughly 22*.
But if you pay attention to what your log is telling you. Final pilot timing is being corrected by ECT somehow.
Sorry. You are correct.
Yeah, I've seen that it is calling out an ECT correction for pilot timing, but there isn't anything to correct for... I am baffled...
If I set the adder and coefficient tables to stock, I get pilot timing logged in the 80*+ range above 2000 rpm. It's way too excessive!
Then shut pilot injection off at 2000rpm.
With your all of your pilot timing tables stock. What is your pilot timing just cruising down the road steady at 1800rpm?
You may have angered something by changing the tables so drastically.
Lets have a look again at my own 2004.5 truck. Stock pilot timing adder and coefficient tables.
ECT @ 140*F
Pilot timing correction reason = coolant temp
Untitled (1).png Untitled (2).png
With the above info, my math has calculated final pilot timing at 40*.
Log shows 38.6*
Close enough for me.
ECT = 190*F
Pilot timing correction reason = base table
Untitled (3).png Untitled (4).png
Since it appears that once ECT is up to full operating temperature the coefficient table becomes inactive my math shows 49.5*
Log shows 48.7*
Also close enough for me.
Last edited by Moparmatty; 02-11-2016 at 08:21 PM.
Hmmm, I never thought of that. I will admit that's the closest I have seen the math add up. Did you take a look at the log and tune I posted? Of course I kind of went extreme with the numbers. I'm going to look through some logs and do some more testing tomorrow and see if I can get the numbers to add up.
Just for curiosity's sake, what is your lift pump pressure at idle? After looking at this it looks like the ecm is trying to max the milliamps to the fca to keep rail pressure in check and it appears to be working, but you might be on the verge of problems. Kind of off topic, but it could help you out.
That's a good catch... I never considered that it might be showing the milliamps after trying to go lower than 0% duty cycle.
My lift pump pressure is at 23 psi at idle. May have to see if lowering that a little changes the idle FCA DC%.
For reference, it is an II DragonFire CP3 pump (their claimed 85% over stock pump), which I believe has a modified FCA.
I don't think it is showing the milliamps, although looking at old logs of my truck they are within 100 of each other. Mine was doing the same thing, but it would actually start creeping up to 12-13k psi rail pressure at idle. Ended up lowering my lift pump pressure to around 16-17 psi to make the ecm happy.
Well, considering how close the logged reading is to this after reaching 0% Duty Cycle on the FCA:
FCA DC to Milliamps.png
I don't know, seems a little coincidental to me. But maybe I'm just reading into things too much.
Also, looking at the FCA Desired, it doesn't seem to be following the base map at all, so I'm not even sure the channel is reading properly.
Could be, it is definitely close. FCA duty cycle desired seems to be pretty worthless, milliamps is the best way to see what the FCA is doing.
Last edited by Kill; 02-11-2016 at 10:27 PM.
Just to throw some more confusion into the mix, I loaded this file in and started it. It started with no pilot (white smoke) then once it changed over from the start soi map to the main soi map, it ran smooth. At no time did it log a pilot inj. ect x iat pilot soi correction table is zeroed and the coeff table is 1. Truck had been sitting all day and it was 100*F ambient temp. It never fired a pilot shot from start up through to 140*F at which time I idled it, and revved it a few times, before shutting it off. Thoughts??
2004.5 pilot experiment.hpt
So you are trying to run pilot only at idle?
This has been discussed in other threads, that the ECT correction may be mis-labeled, and causes issues if zero'ed out.
Try putting a value slightly higher than your requested quantity with a multiplier of 1 and it should do what you want.
2003 305/555 QCSB Cummins
Piston/rod/sleeve/fire ring/dual CP3/300 overs
Super Stick NV5600
S366/S480
Trying to run pilot at low load only. Just thought I'd confirm on mine at least that zeroed adder table equals no pilot. Is there any word yet on when this issue will be looked at?
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