i have a brand new girnatelli maf on my 86 iroc tpi and its throwin a code 33 ,could this be just an adjustment since its adjustable,or is it simply a defective sensor?if it it is just an adjustment does anybody know the correct way to set an adjustable maf?any help would b appreciated.thanks in advance,Joe

 

The better sensor to use may be the improved OEM replacement thats available for the Bosch MAFs. It might be better then using the screenless MAF from Granatelli. The flow straightener is needed to help properly direct teh airflow through the MAF and across its sensing elements.

Can you datalog? If you can, you can observe the BLMs and adjust as needed, but youll need a wideband to fully match the curve thats programmed into the ECM. Also check the voltage output of the MAF to make sure it really is working.

 

why did you need an adjustable maf?

 

Itook the flow straightener out of it ,could that b my prob,if so than how is everybody doin this to stock maf's? thanks for the reply
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cause i put a ram air setup w/k&ns,amongst many others ign,exh ,AFPR ,hypertech chip ,i read somwhere that if u dont upgrade the maf sensor that u aint getting the most out of your mods,is this correct?

 

well it is possible but i dont think it is nessecary. i would have told you to skip the hypertech chip and Afpr.
the only thing hypertech can really do for performance is bump timing which is the only really safe and efective thing to do as the knock sensor will detect any detonation and retard timing. well that and turn you rad fans on sooner. and the afpr is only really useful if you go to bigger injectors and are programing your own chips as the ECM will learn how to operate under the new preassure to the programing on the chip so unless your injectors are going static= open 100% of the time then it isnt useful...yet...

 

so the AFPR is pretty much useless unless i install bigger injectors?,cause i installed brand new accel 19lb/hr performance injectors to.

 

arent the stock ones 19lb/hr? where you old injectors not working? i believe the "performance" part of that is that they have a longer duty cycle. basicaly you can run a lower FPR and achive the same A/F but you would only need to increase injector sizes to support more hp but the mods you have dont realy require it

 

heres a list of all mods= summit racing 52mm throttle body,girnatelli adjustable maf,k&n air filters,ram air setup,bbk aluminum underdrive pulleys,accel 19lb injectors,accel hei supercoil,accel performance ignition module,accel 8mm wire ,bosch +2s spark plugs,crane cams AFPR,COOlant bypassed throttle body,hooker headers & y pipe,flow tech 3'' catback exhaust, 180 dgree termostat,hypertech thermomaster prom chip,port & polished cast iron heads ,shift kit ,hopefully this will help.
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even with all the above? what about the code 33 ,it didnt throw the code 33 til about 50 mph ,what would u suggest ?

 

well yes even with those mods 52mm tb isnt really nessecary as that isnt what is limiting the TPI and the port and polish wouldnt have increased CFM enough to warrent new injectors or the afpr as the ECM could probably have compensated for those slight gains
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when you order the MAF did you specify code C for your coldair/ramair intake?
i would first try the maf with the stock chip to see if you still get the SES then dont i would call hypertech and granatelli and figure out what is going on

but you can test it with a volt meter it should read about .5 volts at idle and 4.7 at WOT if it doesnt adjust it any way you can to get those reading and the code should go away

on granatelli's site they say if you have a cold air intake or ram air (samething) that it will throw a code if you dont order the MAF with the C calibration