Unexplained stalls, unexplained low PW.
#1
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I must be missing something. Can someone take a look at my tune/log and let me know what I am missing?
Notes: At 41.17 seconds I begin decelerating by taking my foot completely off the accelerator and out of gear (as I had done several times previously in the log). For some reason though, my PW drops to 1.2ms or so and approximately 17kpa. This causes a stall. I tried replicating this problem several times but could not. It seemingly happens randomly. Help me find the missing link please!
My fuel PW SHOULDN'T be dropping that low. I cannot find out why it is doing so. Over-run fuel cut is turned off. TP DE is set to 0 fuel removed. What is my problem?
I tried adding a row of super low load numbers with high VE but that didn't make enough difference.
Notes: At 41.17 seconds I begin decelerating by taking my foot completely off the accelerator and out of gear (as I had done several times previously in the log). For some reason though, my PW drops to 1.2ms or so and approximately 17kpa. This causes a stall. I tried replicating this problem several times but could not. It seemingly happens randomly. Help me find the missing link please!
My fuel PW SHOULDN'T be dropping that low. I cannot find out why it is doing so. Over-run fuel cut is turned off. TP DE is set to 0 fuel removed. What is my problem?
I tried adding a row of super low load numbers with high VE but that didn't make enough difference.
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Thoughts from FB:
Ok, so I have a couple ideas: first, my required fuel calculation could be off. I am using ID1000 injectors and at my fuel pressure (58ish) I understand they should be 1200cc. If that is too high it overstates what "1" unit change is in my VE map correct?
Another possibility is that my deadtime is incorrect. My numbers from ID seem to suggest a 1.203ms deadtime (for 4 bar fuel pressure). Does this sound correct?
Another question: does PW in the logs refer to how long the injector is firing or how much fuel the injector is injecting regardless of the dead time? In other words, would a 1.17ms PW on a 1.2ms deadline injector say that it's injecting 1.17ms of fuel or that it's never actually squirting any fuel because it's still within its dead time?
- Answered my own question from the manual: "The base fuel pulsewidth for injector channel 1. This is the actual electrical pulsewidth including deadtime, but
- So... why is my PW shorter than my dead time? Assuming of course my dead time assumption is correct.
Ok, so I have a couple ideas: first, my required fuel calculation could be off. I am using ID1000 injectors and at my fuel pressure (58ish) I understand they should be 1200cc. If that is too high it overstates what "1" unit change is in my VE map correct?
Another possibility is that my deadtime is incorrect. My numbers from ID seem to suggest a 1.203ms deadtime (for 4 bar fuel pressure). Does this sound correct?
Another question: does PW in the logs refer to how long the injector is firing or how much fuel the injector is injecting regardless of the dead time? In other words, would a 1.17ms PW on a 1.2ms deadline injector say that it's injecting 1.17ms of fuel or that it's never actually squirting any fuel because it's still within its dead time?
- Answered my own question from the manual: "The base fuel pulsewidth for injector channel 1. This is the actual electrical pulsewidth including deadtime, but
- So... why is my PW shorter than my dead time? Assuming of course my dead time assumption is correct.
Last edited by Chiburbian; 09-10-2017 at 05:16 PM.
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I think I found something. On my way to work today after twiddling all the ***** I could think of, I noticed that I was still stalling. However, I did notice that when my clutch was in, I wouldn't stall. This leads me to think it's related to my clutch switch somehow. I think I have a wire crossed internally that is shorting... something?
I am going to check my wiring plan and post again later.
I am going to check my wiring plan and post again later.
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Found it guys.
Like an idiot I routed my vacuum line against the firewall in a way that allowed it to be pinched by the clutch every time I pushed in the clutch. So, sequence was:
High RPMs, High vacuum decelerating to about 1500rpms. Clutch in and immediately died. Fixed now.
Vacuum hose routed properly and it's running better than it has in years.
Like an idiot I routed my vacuum line against the firewall in a way that allowed it to be pinched by the clutch every time I pushed in the clutch. So, sequence was:
High RPMs, High vacuum decelerating to about 1500rpms. Clutch in and immediately died. Fixed now.
Vacuum hose routed properly and it's running better than it has in years.