ok so my car is overfueling guzzling fuel like it's going out of fashion. No check engine light but ecu reads code 12 air flow meter circuit??. Things I've done....changed spark plugs and fuel filter. Problem started after I replaced the very old tatty crumpled cone air filter. When I say bad...it was that blocked that the engine had almost crushed it inwards trying to draw air in. I'm guessing that the engine over fueled to compensate for lack of air?? I don't know as I'm new to this. I did remove and clean the MAS with proper cleaner for the job and re installed. At first car wouldn't start and when it did it was rough but then I realised I hadn't connected the sensor, so plugged that in and running smooth again but still overfueling. Someone said I need to get it tuned... I just need help please:scooter:

did you reset the ECU after changing the air filter.

Someone mentioned to disconnect battery for few hours but resetting I don't know how too?

In theory that should have reset it, but it may take quite a while with a Z ECU. I am pretty much positive my ECU was reset recently, as it ran like a bag of bolts when I started it up, but the battery had been off for days, not hours. I think your ECU will definitely have MAF issues if not reset after changing the airbox/filter, because suddenly it's getting way less air than usual if you've put a standard airbox back on it and way more than usual if you've put a new cone type filter on it.

Well it had this cone filter on all be it clogged and crushed so I fitted a new one. Someone said the japs know their cars and I should re install a standard air filter

I think that person doesn't know the Z. I've been told by people who really know what they're talking about and the airbox is one of, if not THE most restrictive part of the air system.

Ok so leave that alone...someone else said O2 sensors

If an/the 02 sensors fail, then yeah that'll make it overfuel too. Dunno if there is a test for that other than Conzult.

Yeah true. Oh well all winter to get it sorted lol