What should SR20 z32MAF IDLE voltage be? (contains ECU logs)

[MJD5SS]

Car: Nissan Pulsar N15
MAF: Z32
Injectors: 370cc
Turbo: T25
car has been tuned by CRD, was absolutely fine for about 8 months, now all of the sudden I have to keep tapping the throttle to hold idle while warming up. Once hot around 90 degree it idles like a dream! all problems gone.

-Removed cleaned and rebuilt IACV, also the AAC.
-No boost leaks.
-Base idle adjusted.
-TPS 0.45v
-ECU throwing code 12 AFM

Only way it will idle is if I completely screw in the idle screw and adjust the throttle stop screw so that the IACV is not being used.

I conducted a log and guess what I found, MAF voltage looks low? could that be the reason? after 7 months and a lot of friggin' around & shit cold idle.

Ignition ON:


Cranked over:



Full logs can be viewed here:

Start + Idle + little rev https://docs.zoho.com/file/1m466f465e4e ... a65b383a9b

Key ignition ON https://docs.zoho.com/file/1m4665abfb64 ... aa18d58f42

I also throw MAF fault code too every now and then

http://www.youtube.com/watch?feature=pl ... Uf6TIW1xMA

[unreal-]

If its throwing a MAF code, replace the MAF

[MJD5SS]

Just weird because it drives on boost and off just fine?

cheers for the input.

[unreal-]

MAFs can be weird creatures sometimes and tend not to make much sense when they go bad. Do you have any screenshots of the MAF at higher RPM/load? Those values look pretty normal for a maf at low rpm/throttle angle.

[MJD5SS]

nothing at higher load, I will do another test tomorrow and upload the results.

[MJD5SS]

Hey again, this is the WOT squirt, and feel free to scroll through the log aswell, its around line 1000 on the spreadsheet.

https://docs.zoho.com/sheet/ropen.do?ri ... 7e19ce3037

[unreal-]

Looks pretty normal to me. MAF voltages at WOT seem to correspond with the amount of power you would be making with the T25 and that engine. At first i thought it was a little low (usually is over 4.0v at WOT) but that is when you start to push over 350whp. I forgot that MAF's voltages increase with the amount of air that flows through them. Since the Z32 MAF is good for around 500whp, Its not going to be pushing that much voltage at WOT because its not being used to full capacity.

If possible, i'd swap MAF's with a known good one to see if that fixes the problem and gets rid of the CEL.

[MJD5SS]

ok I'll try

[MJD5SS]

Confirmed MAF is dead, I plugged my stock DE maf in, and its double what it was with the Z32, Started it from 45 degree coolant temp, didn't miss a beat all the way up into the 90's. Wow idle is smooth as now!! car goes alot better and doesn't smell like raw fuel whilst idling too, Keep in mind I do run a test pipe.

Now the real test is tomorrow, dead cold start, I have good faith in this one.

[MJD5SS]

WOOO FIXED!!!!!!!

[unreal-]

hahaha glad you got it figured out


Now get another Z32 MAF and kick ass!

[MJD5SS]

Nar I'm staying the standard Maf, car pulls harder.