Wiiiierd problem....MAF causing trouble!!
10-05-2007, 03:15 AM
#11
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57lbrs...I dont have any leaks either 
I kinda wish i did so i could fix it lol. I'll double check again though just to be safe. Ill run a scan with it on tomorrow too and post up the file.
I kinda wish i did so i could fix it lol. I'll double check again though just to be safe. Ill run a scan with it on tomorrow too and post up the file.
10-05-2007, 09:58 AM
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Siemens injectors i think...god its been so long since i bought all the stuff. Ill triple check that too. I was looking for some post leaks this morning and the only one I can htink of is in the valve cover!!! I switched my heads to the 98 fbody head style to get the perimeter bolt pattern. Well the valve cover, where our pcv normally is, has a plastic piece with a nice size hole in it. Would this be the cause of my problem you think? Oh and I live neer fairoaks mall...route 50 + FFX county parkway
10-05-2007, 10:00 AM
#14
Siemens injectors i think...god its been so long since i bought all the stuff. Ill triple check that too. I was looking for some post leaks this morning and the only one I can htink of is in the valve cover!!! I switched my heads to the 98 fbody head style to get the perimeter bolt pattern. Well the valve cover, where our pcv normally is, has a plastic piece with a nice size hole in it. Would this be the cause of my problem you think? Oh and I live neer fairoaks mall...route 50 + FFX county parkway
on Legato Rd. I'll be out that way tuning a truck and meeting some friends for work pretty soon.
A leak that size could definitely be the problem.
10-05-2007, 10:03 AM
#15
Injectors:
Are these them?
http://www.racetronix.com/3172FM.html
Seimens 57#/hr (@43.5psi)
If so, they actually flow 65.8#/hr on GM pressure (58psi).
Are these them?
http://www.racetronix.com/3172FM.html
Seimens 57#/hr (@43.5psi)
If so, they actually flow 65.8#/hr on GM pressure (58psi).
10-05-2007, 12:50 PM
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I think those are them actually. I honestly need to check though cause I cant for the life of me remember if I bought them used/new or new from the manufacturer.
The hole in the valve cover is where our pcv on the trucks normally would be. Well I never connected it to anything on this new setup so it's a wide open hole right now. I'll stop by the parts store and get some hose for it and try connecting it to the pcv port on the intake mani. I'll keep you posted
The hole in the valve cover is where our pcv on the trucks normally would be. Well I never connected it to anything on this new setup so it's a wide open hole right now. I'll stop by the parts store and get some hose for it and try connecting it to the pcv port on the intake mani. I'll keep you posted
10-05-2007, 06:13 PM
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Well...I tried puting the PCV back on and no good. I still get the same missfire code P0300 EPA pending, and the other P0300 thats states it is on. Wierd thing I noticed is that it's not setting off my SES light!?!?! 
Any more ideas?? I also tried to change the flow rate and it didnt make any difference either. Anyone think I have a vaccuum leak? Would that cause the missfire code?
Any more ideas?? I also tried to change the flow rate and it didnt make any difference either. Anyone think I have a vaccuum leak? Would that cause the missfire code?
10-06-2007, 03:30 PM
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DC Justin....you da man dude!! It finally worked. I remember someone else posting in this thread saying they had the same problem so hopefully this will help them too. First thing that was wrong i my tune, as DC pointed out, my fuel flow rate was off since i have the 57lb siemens injectors. I changed it to 65.8lbs. Next thing that was wrong was the fact that i left te PCV port, on the valve cover, open. God only knows how this thing was running still lol. Ok so after fixing both issues, i kinda jmped the gun saying that it didnt work, cause i completely forgot to check my tune again. Well...let me say, it was F!*#*ked. My trims were through the roof hitting 23%. After I VE tuned them out, i scaled the MAF, and bam, no more code...and the TCC locks and unlocks like its supposed to!! Thanks alot guys for your help.
DC we should get together sometime man. I'm always looking for someone to share ideas with about these GM's.
Another note: I notice something else which was really cool. I had the wrong injector size in my flow rate right!? So I was telling my pcm that i had 57lbrs in there when i really had 65.8lbrs. So naturally I was running very rich. A whle back i remember a few of you guys switching to the Granatelli MAFS, which is known to lean out the system. I think you get were im going with this....has anyone tried fooling the PCM by making it think you have smaller injectors, then put the Granatelli MAF on and see if it puts the curves back to where it's supposed to be?!? Also another cool idea for people running boost without a fuel management system!!! If the pcm "thinks" you hae smaller inectors than you actually do, then it will always be adding more fuel than its actually supposed to. By using wide band O2, you might be able to come up with some interesting results. Maybe even save some money on an expensive full management system
DC we should get together sometime man. I'm always looking for someone to share ideas with about these GM's.
Another note: I notice something else which was really cool. I had the wrong injector size in my flow rate right!? So I was telling my pcm that i had 57lbrs in there when i really had 65.8lbrs. So naturally I was running very rich. A whle back i remember a few of you guys switching to the Granatelli MAFS, which is known to lean out the system. I think you get were im going with this....has anyone tried fooling the PCM by making it think you have smaller injectors, then put the Granatelli MAF on and see if it puts the curves back to where it's supposed to be?!? Also another cool idea for people running boost without a fuel management system!!! If the pcm "thinks" you hae smaller inectors than you actually do, then it will always be adding more fuel than its actually supposed to. By using wide band O2, you might be able to come up with some interesting results. Maybe even save some money on an expensive full management system
The next time I'm out your way for lunch, I'll shoot you a PM and we can meet up.
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