what is going on in these logs. boost leak, bad N75, bad maf?
02-22-2007, 05:42 PM
#1
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what is going on in these logs. boost leak, bad N75, bad maf?
<center><img src="http://i128.photobucket.com/albums/p167/nmanchin/2-22loglarge.jpg"></center><p>
boost fall off problem (sporatic, doesn't happen every time) you can see at 4520 revs drop
g's look a little low, but n75 is what i don't understand, what tells it to go so low. i'll be pressure testing this weekend. also have a brand new N75 sitting beside me.
boost fall off problem (sporatic, doesn't happen every time) you can see at 4520 revs drop
g's look a little low, but n75 is what i don't understand, what tells it to go so low. i'll be pressure testing this weekend. also have a brand new N75 sitting beside me.
02-22-2007, 06:15 PM
#3
Programming ...>>>
Tells the N75 what to do (based on all sensor input). Maf looks good in run 2, a little weak in run 1 and that shouldn't really change. In run 2 the N75 is going back up to 94% to keep that boost level up....Unfortunately This does not look much different from some other Giac logs I've seen. No telling what the control issue is...could be a program glitch
02-22-2007, 06:21 PM
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if you don't find a boost leak, get your ecu reflashed
that fixed my problem (also GIAC) after people on the forum scoured log data for me time and time again (thanks guys!) looking for possible indicators of a hose leak or faulty N75.
02-22-2007, 07:08 PM
#7
Problem is...>>
Actual IC boost is almost exactly Command boost (what the ECU is calling for) which would seem to rule out a leak in run 1. In run 2, the N75 rate ratchets up to maintain boost which could be a leak. You may have an intermittent one...
Only look at command and IC. Manifold boost levels are calculated off MAF output and are not accurate.
Only look at command and IC. Manifold boost levels are calculated off MAF output and are not accurate.
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02-22-2007, 07:21 PM
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Check block 020 and 118 for timing retardation and intake temp >>
If timing is retarded more than 7 degree on block 020, ecu will start limiting the boost causing MAF to read lower and all the other modules will read lower. Intake temp is usually proportional to timing retardation.
02-23-2007, 04:48 AM
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so in theory run 1 could have been a soft limp situation
from the intermittant leak. i really feel like there it a leak. it ran perfect for a couple of weeks after i found all of the past leaks. probably another one from me tinkering with it so much. just a matter of finding it.
i did have that 16826 EVAP small leak code pop up late last week to never return.
i did have that 16826 EVAP small leak code pop up late last week to never return.
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