I've had no success fixing AFM. They use a potentiometer, like a fuel gauge sender (variable resistor). Chances are it is corroded. Maybe inspect it. You can try it!

Thanks DD.
So, the AFM is not repairable?
Can I try to spray WD40 on the flap?

I'll look into the megasquirt. But I like to have it as factory setup as possible..

Quote:Yes, but is not calibrated to the non-programmable Nissan ECU.

You can use Nissan Silva S110 ECU + AFM (use a matched set)

Or, buy a $400 aftermarket ECU and do it yourself. See EGI MegaSquirt

Thanks DD.
The above set is not from running engine.
The AFM flap is freeze.
Is it repairable? Or any other Nissan AFM will work?


Workshop quote me around usd 1000 To make the engine run with aftermarket ecu.

Quote:Don't you already have a matching set? Your first photo shows both parts. Try it and see if it works. Datsun guys here in USA have used Hitachi ECU on different size and type Nissan four-cylinder engines with good results. In the photos above, the ECU looks undamaged, and I see no corrosion on the circuit board. Check the AFM flap to see if it moves smoothly and is undamaged

You could also use an aftermarket engine "computer". That'll work too and is fully programmable. See our tech article "ECU" for a brief discussion of several choices

The Datsun ECU is a "stand alone computer". It is self-tuning to some extent, although it is not fully programmable like a modern unit (it doesn't have a "chip"), and it doesn't need one

The Air Flow Meter (AFM) is the flapper gauge unit. The A14E ECU is calibrated for the A14E AFM, and so can handle different size engines as it measures the airflow. While the A15E engine has same airflow at 6400 rpm as A14E engine, A15E has more airflow at 4000 RPM. The combination of ECU/AFM measures the air so it can determine how much Fuel to deliver (it controls the A/F mixture). Both engines use the same a/f ratio of 14.7:1 at cruise, along with full-throttle enrichment. 14.7 is required by the Catalytic Convertor, although the engine will run smoother at richer a/f ratio

I went to few workshops today. No one advice me to use the computer box in AFM. Unless it is from a running engine. They advise me to use a stand alone computer. I'm confused, should I run this with stand alone computer or look for another original set from running engine?

Thanks. The wideband cost around 50-100 USD from eBay. Very useful device.

If you can afford it or have it, use wideband / a/f to keep a lookout if you mix is rich or lean, then you can check if the engine is getting to little or too much fuel, as that is the only aspect you are changing

many thanks...

this egi set is from a chopshop which never been running for many years..
so what is the precaution i should take?