Please look @ tune, air flow issue after cam swap
#1
Please look @ tune, air flow issue after cam swap
3rd time w/ different cam. Am obviously making some stupid install mistake.
Please look @ log file. Any clue as to what's wrong? I know A/F is off. Am posting the tune to reference the lack of air flow. Air flow & injector duty are down 50% & watch the MAP drop to 30 on shifts. Idles @ 58.
Installed dot to dot & degreed the cam every time. WTF am I doing wrong w/ the cam install? As noted have installed 3 different times, 3 different cams since last Fall. Number 1 cylinder is TDC when dot to dot. I am making the same mistake every time.
Please look @ log file. Any clue as to what's wrong? I know A/F is off. Am posting the tune to reference the lack of air flow. Air flow & injector duty are down 50% & watch the MAP drop to 30 on shifts. Idles @ 58.
Installed dot to dot & degreed the cam every time. WTF am I doing wrong w/ the cam install? As noted have installed 3 different times, 3 different cams since last Fall. Number 1 cylinder is TDC when dot to dot. I am making the same mistake every time.
#3
Just for confirmation as to what was done, TDC is set up as TDC just prior to the #1 cyl starting the intake (vacuum) stroke & as if engine rotates in a clockwise direction when standing in front of the balancer.
#5
Thanks for the note. I run open loop MAF. In this case, it's the cam set up that's causing the problem. The tune is confirming the lack of power felt while driving. Posted the tune for everyone to see the small amount of air being moved through the engine. Also, posted in this section (internal as well) because the guys in here understand both the mechanical & tuning side of it. Am thinking that someone will find something that I just can't see. The engine iteself is moving half of the air that it should. Something is wrong w/ my cam set up. I'm just too aggravated & ignorant to figure out what was done incorrectly 3 friggin' times in a row. I even had the engine on a stand when this cam was installed.
#6
Found blown 15A fuse in under hood control center 2. Fuse is linked to MAF, bank 2 sensor 1 & brake switch. Don't know if this by itself is the root of the problem. Will post again once fuse is replaced. Did have an O2 code, but had been having trouble w/ that sensor & ignored it. It's not used to control fueling & trims related to it @ idle are set low. Figures, I had already completely re-wired the rear brake lights w/ a new switch. Thought it was the switch.
#7
TECH Senior Member
iTrader: (25)
The Eng Sens fuse powers the MAF and all 4 O2 sensors. With it blown it was in SD mode and since you run open loop MAF, you were probably logging MAF output in SD mode. I don't have the right version of EFILive installed to look at what you posted. Sucks you changed cams 3 times over that. It should have set a MAF low output code too with that fuse blown.
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#8
The Eng Sens fuse powers the MAF and all 4 O2 sensors. With it blown it was in SD mode and since you run open loop MAF, you were probably logging MAF output in SD mode. I don't have the right version of EFILive installed to look at what you posted. Sucks you changed cams 3 times over that. It should have set a MAF low output code too with that fuse blown.
I was wrong about the MAF, O2 & brake switch circuit. My schematics are poor quality & I missread the current rating of the fuse that protects that circuit. That fuse is a 20A fuse & was not blown. There are now (2) blown fuses that I found. Both fuses are 15A. From my schematics, it looks like one 15A fuse protects the evaporator purge solenoid circuit & shouldn't matter unless the PCM needs the feedback, because it's disconnected. The second 15A circuit looks like it could be the #2 injector circuit or the ign circuit. There are several under hood fuses that aren't on the schematics. So, it could be something else. We will see once I can test it. Fuses have been replaced.
I does suck that the cams were changed 3 times. Only good parts are that the car now has a fresh short block & I'm well practiced on cam swaps.
#9
TECH Fanatic
iTrader: (25)
Somethings wrong with the O2 sensors.
One hardly switches at all and the other is not switching right,
they should average 450mV and AFR is lean overall.
How do you know airflow is not what it should be when you're not logging {GM.MAFFREQ}?
With out that PID selected you have no hope of matching logged MAF to {B5001}
The MAF table needs to be re-scaled just like the VE table.
One hardly switches at all and the other is not switching right,
they should average 450mV and AFR is lean overall.
How do you know airflow is not what it should be when you're not logging {GM.MAFFREQ}?
With out that PID selected you have no hope of matching logged MAF to {B5001}
The MAF table needs to be re-scaled just like the VE table.
#10
TECH Resident
Just for confirmation as to what was done, TDC is set up as TDC just prior to the #1 cyl starting the intake (vacuum) stroke & as if engine rotates in a clockwise direction when standing in front of the balancer.
#11
Somethings wrong with the O2 sensors.
One hardly switches at all and the other is not switching right,
they should average 450mV and AFR is lean overall.
How do you know airflow is not what it should be when you're not logging {GM.MAFFREQ}?
With out that PID selected you have no hope of matching logged MAF to {B5001}
The MAF table needs to be re-scaled just like the VE table.
One hardly switches at all and the other is not switching right,
they should average 450mV and AFR is lean overall.
How do you know airflow is not what it should be when you're not logging {GM.MAFFREQ}?
With out that PID selected you have no hope of matching logged MAF to {B5001}
The MAF table needs to be re-scaled just like the VE table.
Yes, I know. The new set up has not been tuned @ all. Am waiting to get the car moving correctly first. Noted in the original post to ignore most of the tune. Have not gone back to working on the car yer (Holiday stuff). There's an oil pan gasket leak to fix, then back to testing the cam/electrical stuff. Am hoping that repacing the (2) 15A fuses was a step in the right direction.
Also, realize about the MAF. Although it's not correct, the settings shouldn't be that far off from the previous cam on same heads. On list of tunning stuff once main problem is resolved.
#12
Sorry about the delayed reply. There was the holiday & then had stuff to do for my Son. Ok, car is fixed. It was one or both of the 15A fuses that had blown. One for sure was for the bank 2 injector circuit. Could tell as soon as the car was started that there was a difference. Soon after, the crud on the bank2 header started to burn off from the heat. Hadn't had anything other than air blown through it since the short block swap. Went for a short drive & the "Munster" lives once again.
Sometimes I just can't see the simple things. Spent alot of time on more cam swaps & the short block swap all because of one or two blown fuses. Live & learn, live aannnnddd learn.
Thank-you for all of the help. Can now get into the tune for this new cam.
Sometimes I just can't see the simple things. Spent alot of time on more cam swaps & the short block swap all because of one or two blown fuses. Live & learn, live aannnnddd learn.
Thank-you for all of the help. Can now get into the tune for this new cam.