MAF issue?

dude its the tune, either get it tuned on the dyno or get an safc to lean it
out. gapping plugs and all this stuff isnt gonna keep you from running rich.
 
alx954 said:
dude its the tune, either get it tuned on the dyno or get an safc to lean it
out. gapping plugs and all this stuff isnt gonna keep you from running rich.
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well i have the enthalpy ECU, i dont think it can be that because a tune shouldn't change over time, for some reason my car isnt run like its supposed to, ive seen many KA-T'rs run enthalpy or JWT ECU pretunes without a SAFC fine. I think maybe the MAFS itself may be bad?:confused:
 
this reminds me of the problem i'm having with my SR. runs really really rich. 12.8 mpg last tank. rough idle and almost stalls when i stop. pulls good but shoots a cloud of black smoke out.
 
JoshuaS said:
this reminds me of the problem i'm having with my SR. runs really really rich. 12.8 mpg last tank. rough idle and almost stalls when i stop. pulls good but shoots a cloud of black smoke out.
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hmmm does seem similar, did you find out the cause of the problem?

Also i just checked my ECU for codes...pulled a Code 34, knock/detonation sensor...would a faulty sensor be causing my problems?
 
homeskillet305 said:
bro it's the tune theres nothing broken
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I doubt it dude, why would the tune suddenly change, its not a SAFC, its a ROM tuned ECU and i haven't done anything to mess with it, i cant even change the settings or retune it myself so it couldn't have suddenly gone bad, and remember sometimes my car runs good sometimes it doesn't. If the tune was bad itll always be one, not one and the other
 
get a boost controller and set it like 1 or 2 pounds over what you run and see what your afr is at WOT you might just be at a rich part in the map and sometimes your boost surges and it runs good or somthing like that. or your tune might be for less psi and when you get a boost spike it richens the afr

btw the only thing a shorted/broken knock sensor would do it retared your timing
 
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i put my manual boost controller on last night and for some reason it idles better and doesnt shoot black smoke out everywhere and it doesn't stutter at really low rpm when i'm barely on the gas. But now my BOV is releasing from 4500rpm's till redline at .6 bar then drops below .5 bar. I think i need a new BOV it had an ebay one on it when i bought the car.
 
yea if your bov is leaking you'll run rich all the time while it's leaking since the maf meterd the air but it never made it into the intake mani
 
homeskillet305 said:
get a boost controller and set it like 1 or 2 pounds over what you run and see what your afr is at WOT you might just be at a rich part in the map and sometimes your boost surges and it runs good or somthing like that. or your tune might be for less psi and when you get a boost spike it richens the afr

btw the only thing a shorted/broken knock sensor would do it retared your timing
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hmmm, you may be right dude! :bigthumbu When i had boost surge to 10 psi my car did run alot better, it was in the mid 11s AFR. Ive surged to 10 psi twice and both times the AFR was in the 11s. My current psi is only 7. Supposedly tho the Enthalpy tunes arent tuned for a set psi, since the MAF should read the incoming air and adjust accordingly...but your theory is something im gonna think about.

About the broken sensor, if the timing gets retarded wont that make my richer? and knock most often happen at wot in boost no? thats what i was thinking y know?
 
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homeskillet305 said:
timing will not change the afr but it will change the afr where you make the most power.
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Im guessing that would be at full boost, and its when i hit full boost and the wastegate opens is when my AFRs dive to the flat 10. Maybe it is the knock sensor afterall? im gonna change it regardless to know for sure.
 
so if im have a boost gauge and seems to dont read right the vacuum could this be consider a boost leak and make the car run rich ? (mine is doing it too) i change the maf and still runs rich according to the AEM UEGO

sorry for the thread jack :S:threadjac:arr:
 
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pressure test your ic pipes and see what happens. my freind had a boost gauge that wouldnt go all the way down into vacc sometimes but would read boost perfect. also check your injector o-rings.

and fairlady280z i dont think the knock sensor has anything to do wih it if your car runs fine otherwise.
 
^ yep that is exactly what happes doesnt get to vaccum but it reads boost no prob! ill test the pipes ! thnx man!
 
homeskillet305 said:
pressure test your ic pipes and see what happens. my freind had a boost gauge that wouldnt go all the way down into vacc sometimes but would read boost perfect. also check your injector o-rings.

and fairlady280z i dont think the knock sensor has anything to do wih it if your car runs fine otherwise.
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Thats what a couple of my friends told me, one of them suggested that i may have a injector that is shooting too much fuel, i told them i doubt it cause they are brand new DW 550s and he said what may have happened is that the little plastic caps at the end of the injector may have came off and may be whats causing it...

This may also be what the knock sensor is sensing, he said since the cylinder is getting flooded there is metal on metal contact going on and the knock sensor is picking it up...im gonna pull the injectors this Thursday to see whats up, i suspect it may be cyl #1 since the plug from that one is always a bit darker than the other 3
 
Fairlady280z said:
Thats what a couple of my friends told me, one of them suggested that i may have a injector that is shooting too much fuel, i told them i doubt it cause they are brand new DW 550s and he said what may have happened is that the little plastic caps at the end of the injector may have came off and may be whats causing it...

This may also be what the knock sensor is sensing, he said since the cylinder is getting flooded there is metal on metal contact going on and the knock sensor is picking it up...im gonna pull the injectors this Thursday to see whats up, i suspect it may be cyl #1 since the plug from that one is always a bit darker than the other 3
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yeah...pulled the injectors they were all fine :cool: So yeah back to square one, anyone know where i can get a new OEM knock sensor for cheap?
 
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