Losing Spark/Tach at 5000rpm under load
#21
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Yeah, I think I could handle the setup, but getting it to work would surely be the hard part.
I finally got a chance to peruse my datalogs...and they're showing up as resets! Check record 304 (just before 50sec) in the one below. I was also expecting to see the abnormally high rpm spikes, and they're not anywhere to be seen, so I may have a different problem.
I finally got a chance to peruse my datalogs...and they're showing up as resets! Check record 304 (just before 50sec) in the one below. I was also expecting to see the abnormally high rpm spikes, and they're not anywhere to be seen, so I may have a different problem.
#23
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Thanks for the advice Matt.
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Pulled my grounds out again over the weekend...need to go get a big lug as I want to solder EVERY ground that is there (5 wire) onto ONE lug to see if the multiple lugs were giving me noise.
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I was just thinking the other day I needed to update this thread...glad you reminded me.
So far the re-done grounds seem the be holding up.
I also put in some DIY urethane motor mounts...and a beefier engine ground.
My theory is the motor was moving just enough under high rpm torque to tug and shear the OEM driver's side engine ground...which was killing my reference voltage as Matt stated.
I've yet to take a log as I've been fairly busy with school...but it pulls all the way to redline now.
So far the re-done grounds seem the be holding up.
I also put in some DIY urethane motor mounts...and a beefier engine ground.
My theory is the motor was moving just enough under high rpm torque to tug and shear the OEM driver's side engine ground...which was killing my reference voltage as Matt stated.
I've yet to take a log as I've been fairly busy with school...but it pulls all the way to redline now.
#29
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Okay...I reflashed yesterday...and the car runs better.
The resets had seemed to be load related, and apparently MS wouldn't let the Duty Cycle exceed a certain amount. I'm convinced it's some kind of grounding problem, but had checked, cleaned, and beefed up every ground I could find.
It seems to have gone away int he reflash...but I've yet to turn the boost back up to confirm this. It seems happy below 10psi...but would cut out like crazy after that.
NEW PROBLEM:
Now I'm getting serious duty cycle spikes. I will post .msq and pics when I am done with class...but I can describe.
The pulse width and duty cycle both jump up for a split second, causing AFRs to dip down to 9-10:1. This mainly happens in vacuum (10-20in on boost gauge), and below 4500rpm...basically when I'm cruising in 4th or 5th.
It's violent enough to feel...about like a brisk headwind hitting the car..and causes shifter to move. Really feels like I'm losing spark at the same time...but not sure.
I have:
Reflashed
Replaced ignitor
Replaced coils
Replaced/cleaned grounds
And am still seeing this.
I'm sure Matt hit the nail on the head...and that this is all related to crazy battery voltage. I've seen other datalogs where folks had generally stable battV...and mine has a shitton of noise. I haven't the slightest as to why this is happening. I've checked grounds...do I need to check ECU power?
Any and all input appreciated.
The resets had seemed to be load related, and apparently MS wouldn't let the Duty Cycle exceed a certain amount. I'm convinced it's some kind of grounding problem, but had checked, cleaned, and beefed up every ground I could find.
It seems to have gone away int he reflash...but I've yet to turn the boost back up to confirm this. It seems happy below 10psi...but would cut out like crazy after that.
NEW PROBLEM:
Now I'm getting serious duty cycle spikes. I will post .msq and pics when I am done with class...but I can describe.
The pulse width and duty cycle both jump up for a split second, causing AFRs to dip down to 9-10:1. This mainly happens in vacuum (10-20in on boost gauge), and below 4500rpm...basically when I'm cruising in 4th or 5th.
It's violent enough to feel...about like a brisk headwind hitting the car..and causes shifter to move. Really feels like I'm losing spark at the same time...but not sure.
I have:
Reflashed
Replaced ignitor
Replaced coils
Replaced/cleaned grounds
And am still seeing this.
I'm sure Matt hit the nail on the head...and that this is all related to crazy battery voltage. I've seen other datalogs where folks had generally stable battV...and mine has a shitton of noise. I haven't the slightest as to why this is happening. I've checked grounds...do I need to check ECU power?
Any and all input appreciated.
Last edited by gospeed81; 09-30-2009 at 02:03 PM.
#33
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I've noticed that in a few more recent logs today...so I turned it down.
Any other way to keep it from kicking in so violently at cruise?
I'd like to think I'm pretty steady with the pedal...maybe just truly poor settings. The problem did kind of creep up though.
Any other way to keep it from kicking in so violently at cruise?
I'd like to think I'm pretty steady with the pedal...maybe just truly poor settings. The problem did kind of creep up though.
#35
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ALL PROBLEMS FIXED!
Posting solutions for posterity.
RESETS:
The beefier grounds may have helped, but a reflash cured them once and for all.
RICH AFR SPIKES:
Continued to adjust accel enrichments, and they don't perceptibly kick in during cruise anymore without looking at the datalog. Their slope is much lower on the datalog, and the AFR doesn't move more than 0.75 when it happens, unlike the 2-3 full points as before. I don't wish to lower AE anymore as it seems it would lose it's effectiveness.
SPARK CUTOUT:
One word.....COPS.
Apparently I was blowing out the spark pretty bad, even when gapped at 0.023". This made me hate life...and now I am better. Big difference in power (about half the kick in the butt as full 2.5" exhaust with straight-thru muffler) and MUCH smoother.
Posting solutions for posterity.
RESETS:
The beefier grounds may have helped, but a reflash cured them once and for all.
RICH AFR SPIKES:
Continued to adjust accel enrichments, and they don't perceptibly kick in during cruise anymore without looking at the datalog. Their slope is much lower on the datalog, and the AFR doesn't move more than 0.75 when it happens, unlike the 2-3 full points as before. I don't wish to lower AE anymore as it seems it would lose it's effectiveness.
SPARK CUTOUT:
One word.....COPS.
Apparently I was blowing out the spark pretty bad, even when gapped at 0.023". This made me hate life...and now I am better. Big difference in power (about half the kick in the butt as full 2.5" exhaust with straight-thru muffler) and MUCH smoother.
#37
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Pretty bad misfires. I could feel it during hard acceleration. This combined with the poor grounding and some firmware corruption would make it stop accelerating for a half second right around peak torque.
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