Fake Z32 AFM’s of FAIL!

January 13, 2014

I was on the dyno today (surprise surprise) and just plugged in a PowerFC to a customer’s R33 Skyline…

He’d already installed some 650cc injectors, Z32 AFM and bolted on a Kinugawa TD06 turbo in a low mount setup so after calling us for some advice on either tow down or drive down, we advised to “just cruise” down to the shop and we’d get her tuned up. On a side note, installing the Z32 AFM and injectors approximately double the size almost ‘cancels out’ the effects bigger injectors and a different VQ map the Z32 AFM has on a stock ECU.

So after scaling the injectors down and reconfiguring the AFM in the PowerFC, we usually let the car ‘self learn’ the idle (with and without the A/C on) for about 10-15 mins. It was running a little sloppy on light load, leaner than what I liked so a bit of latency scaling and another check over was required before I could get into some steady state tuning.

After getting the fuel to an acceptable AFR, it was time to do a low boost pull. The fuel delivery seemed a bit inconsistent, quite wavy…. slightly too rich on boost transition then a little lean when the boost curve flattens off. After 5-10 mins of shaping the fuel map to suit, I decided something wasn’t right and usually my first port of call is boost leak test and checking the fuel pressure.

Off with the pod filter and AFM so I could bolt up the boost leak tester and hey presto… this looks a little bit odd… brand new AFM, the sticker side was facing down so after it was pulled from the car I noticed there wasn’t a sticker. A quick look at the element and yeah, she definitely a China/eBay knock off. I usually refuse tuning a car with a non-genuine AFM but without seeing the orange sticker staring me in the face, I neglected to check.

So check out the difference in the genuine vs fake… The genuine (left) has a circuit board, processes the information and sends it back to the ECU. The fake is just a resistor wired into the hotwire… I guess you get what you pay for!

Genuine Z32 AFM vs Fake Junk!

Genuine Z32 AFM vs Fake Junk!

Now check our dyno comparison… Same car, same tune, same boost and different AFM’s.


Our conclusion, stick to the genuine stuff boys and girls!