Mass Air Flow Sensor

[Sorcerer]

My car is currently in my mate's garage for repair as it won't run. The OBD info keeps throwing the code for the Mass Air Flow Sensor but my mate is a bit reluctant to categorically say that yes, the MAFS is the problem because when a MAFS goes faulty, usually the car will run but lacks power, whereas my car won't run at all - it'll fire up but is very lumpy and dies after a few seconds.

Thinking that if it wasn't going to cost much we might as well get a new MAFS anyway, he tried all his usual suppliers but can't get one and the Nissan Main Stealers want £253 PLUS VAT!!

I've looked on Ebay and there are quite a few suppliers who are selling MAFS for £25 to £35 that, according to the description, are listed as fitting my car (such as this one). The descriptions state "Nissan Maxima QX, A33, 3.0, V6, 24V, Petrol, 2988cc, Year 03.00 to - (mine's 52-plated), engine code VQ30DE, ALL of which is correct, but these MAFS listed all have a 5-pin connector whereas my car and existing MAFS has a 4-pin connection.

The official Nissan factory workshop manual wiring diagram clearly shows four wires and 4-pins, with a blank space on the connector where the fifth pin is located as you'll see in the attachment. Does anyone know if that fifth pin on the Ebay-listed sensors is somehow just a blank or is perhaps 'commoned' with one of the other four? In other words, would a 5-pin sensor from Ebay work in a 4-pin system? Or does anyone know where I can get a 4-pin sensor from, other than the main dealers? 

[Trevor]

Hi Sorcerer,

You are correct that when a MAF goes faulty it usually just affects the running and not create a non-start situation.

I would go back to basics and work out why it went wrong in the first place and check the fundamentals (battery feed and EARTH cables, fuel feed, condition of ignition components, etc).

Hope you find the fix

Regards, Trevor - Admin

[Sorcerer]

Hi Trevor, and thanks for your reply mate. As it is, I took a gamble and bought the £25 one from Ebay and it worked brilliantly - the car is now back to its usual smooth-running self.

Having got it back to full health we decided it was about time for a change as we'd had it since 2008, so we traded it in for an 05-plated Lexus RX300

Cheers anyway

[Trevor]

Thanks for the reply...its good to know the outcome as other forum members may have similar issues.

Good luck with the Lexus...great cars!