reduced engine power - HP Tuners
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reduced engine power - HP Tuners
I have a 04 CTSV with a LS7 crate motor, using the stock 04 ctsv computer, same computer in an 04 vette. question is what would cause a reduced engine power code? it seems to happen when I drive in a low gear at a high rep 4000+ without shifting, like prepairing to pass on a two lane highway. I immediately checked the codes using HP scanmaster and it had no codes?
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Reduced power looks to me, to be from the PCM deciding
it can't trust the airflow values because MAF, speed-density
and alpha-N are not agreeing. Sometimes you see this
reported as a TPS code (airflow for TPS & RPM does not
match others) even though it's not the TPS' fault at all.
But it decides not to "allow" you to open the throttle all
the way just in case.
Have you gotten the engine displacement value set to the
LS7's if it's different than orig? Got the VE table trued up
for the cam in that crate motor? That kind of thing?
The fault threshold for these cross-checks may be high
enough that you need to be moving a lot of air to get a
lot of error, hence seeing it only at higher RPM.
it can't trust the airflow values because MAF, speed-density
and alpha-N are not agreeing. Sometimes you see this
reported as a TPS code (airflow for TPS & RPM does not
match others) even though it's not the TPS' fault at all.
But it decides not to "allow" you to open the throttle all
the way just in case.
Have you gotten the engine displacement value set to the
LS7's if it's different than orig? Got the VE table trued up
for the cam in that crate motor? That kind of thing?
The fault threshold for these cross-checks may be high
enough that you need to be moving a lot of air to get a
lot of error, hence seeing it only at higher RPM.
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I was using the scanmaster program, my ve table and maf table may be the culprit, is there an tried and true wau to get these into line? do you know of a base program that I could start off using. I looked in the bin files but could not find one. I did find an LS7 c6 bin file but it is from the new computer, and the values will not allow me to cut and paste on the 04 computer. If i use the maf/ve tables for a given rpm from the ls7 and put it on to the table manually will this work? the only difference I have seen is that the new computer has more varables and reads more than the old computer?
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I had the reduced power mode happen to me, here is the thread with the info from the EFI Live boards, culprit was table C6101.
http://forum.efilive.com/showthread....ighlight=table
http://forum.efilive.com/showthread....ighlight=table