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Old 06-02-2014, 10:57 PM   #1
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Exclamation Wierd Missfire, Please Help Log and Msq included

Hey guys so I been having a strange missfire issue that started just days ago,
first I though it was the CAS which was wonky and tired so I replaced it and its alot better but its still there, have a look maybe Im missing something.

FIY note Dutycycle 2, its been like that from day one, is this normal for a PNP Gen 1?

relevent Specs:
1.6 Stock
MSpnp Gen1 running HR10G
Toyota COPS with resistor and Cap
PTE5531 Turbo .48 Hotside
2.5" Vband DP to 3" no cat
TACO TACO Log Manifold
Tial MVS external gate VTA
LC1 Wideband
DW 600cc Injectors
Walbro 255HP
Water/Meth injection (on sererate switch and not connected to ECU)
Electronic Boost control
Moded J&S Ultra safeguard 2CH (completley uninstalled since before issue started so it aint that)

anything else you need just let me know
Attached Files
File Type: msq HR10G_PTE5531.msq (41.6 KB, 56 views)

Last edited by NorthernlightR; 06-04-2014 at 07:48 PM.
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Old 06-02-2014, 11:03 PM   #2
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I had to trim the Log down otherwise would not upload, even at 3mb, oh well here it is..
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File Type: msl 2014-06-02_15_modified.msl (63.1 KB, 45 views)

Last edited by NorthernlightR; 06-03-2014 at 08:16 AM.
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Old 06-03-2014, 10:21 AM   #3
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The duty cycle is a MegaTune glitch on MS1 - it's not really happening.

Looks like you bounced it off the overboost protection there. You want to set the overboost protection well past the point you're actually boosting to - it's a "ZOMG SHUT OFF THE ENGINE NOW!!! TOO MUCH BOOSTS!!!" sort of setting.
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Old 06-03-2014, 08:08 PM   #4
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Quote:
Originally Posted by Matt Cramer View Post
The duty cycle is a MegaTune glitch on MS1 - it's not really happening.

Looks like you bounced it off the overboost protection there. You want to set the overboost protection well past the point you're actually boosting to - it's a "ZOMG SHUT OFF THE ENGINE NOW!!! TOO MUCH BOOSTS!!!" sort of setting.

Ya I know what you mean so I already tried raising the boost cut for testing however have a look at the max boost in the log when it happened and then compare to my over boost setting which is set higher. (17.9psi). What is going on?
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Old 06-04-2014, 11:18 AM   #5
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You're at 15.7 psi boost relative to your barometric pressure reading. A tiny bit of noise can trigger the cut even if the noise pulse isn't fast enough to show up in the log. Raise the overboost threshold.
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Old 06-04-2014, 07:47 PM   #6
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Originally Posted by Matt Cramer View Post
You're at 15.7 psi boost relative to your barometric pressure reading. A tiny bit of noise can trigger the cut even if the noise pulse isn't fast enough to show up in the log. Raise the overboost threshold.

If it was a overboost trigger why didn't it pull spark as well? I have mine setup to pull fuel and spark.
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Old 06-05-2014, 12:28 PM   #7
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Only the fuel cut shows up in the data log; the spark cut isn't as easy to find.
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