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Hi guys,

I took my car to the mechanic and he showed me that my 2 air flow meter plugs where disconnected.. He said that this would affect the air flow mixtures and possibly even power output.

Since my car isnt running properly now there is no way to test if this would increase my power now that they are plugged in.

SO what affect would unplugged air flow meters have on a cars preformance, just more fuel bieng pumped into the engine yeah?

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rev limit = 2500rpm

I'm confused buddy, your saying that it would only rev to 2500 rpm?

But i was redlining it no problems, and it didnt feel like i had lost any power to be honest with you.

I didnt even notice the difference than from the stock air box.

with standard ECU and standard setup if you unplug the airflow meters the RPM will cap at 2500rpm and it will be limp mode

there is no way known the stock ECU would run std maps with airflow meters unplugged, its suicide and the engine has no idea how much air is coming in

double check again or maybe you have some wierd remapped std ecu with a map sensor hack / hks vein setup or something look

look for map sensors and crazy wiring if thats the case

and are you sure he said air flow meters?

it could have been 02 sensors, they are on the dump pipes, the airflow meters are pink labelled plastic things on the air intake pipes

if it was the 02 sensors, the car will run fine, it will just waste a bit of fuel on cruise and your economy wont be the best - no power gain by reconnecting them

with standard ECU and standard setup if you unplug the airflow meters the RPM will cap at 2500rpm and it will be limp mode

there is no way known the stock ECU would run std maps with airflow meters unplugged, its suicide and the engine has no idea how much air is coming in

double check again or maybe you have some weird remapped std ecu with a map sensor hack / hks vein setup or something look

look for map sensors and crazy wiring if thats the case

Thanks man, i have gone an investigated everything you recommended.

First of all i must have a stock ecu as it has the Nissan seal is still on it:

But someone has cut a red wire from it and tapped up the end so it doesn't short anywhere.. what is this wire and why would they do this? take a look:

post-49206-1211601180_thumb.jpg

Also the i have circled in red the 2 plugs they found disconnected this morning:

post-49206-1211600948_thumb.jpg

I think we are getting closer to an answer thanks again!

see my pic - ive circled in red the true AFM plug, trace where the wires go

post-2054-1211604327_thumb.jpg

Good news i traced the wire back and its just the O2 sensor.

Ow well no extra power from plugging it in then.. :P

seen that red wire cut before on the ECU before?

cheers for your help buddy.

no worries - yeah 02 sensors unplugged wont cause harm, but you should plug them in, get some better economy

the red wire could be anything - its probably the speed cut wire, does it the stock ecu cap out at 180km/h on the track?

no worries - yeah 02 sensors unplugged wont cause harm, but you should plug them in, get some better economy

the red wire could be anything - its probably the speed cut wire, does it the stock ecu cap out at 180km/h on the track?

Yeah thats what i thought straight away too.. i havent been to the track yet to test 180km/hr speed cut.

I really want to head down to the track actually so i might become a SAU paying member since i hear they organise heaps of that stuff quite frequently.

The dudes got a PFC ne way so... :)

Actually dont have one yet, but i am trying to source one atm. Waiting on a few PM's from ppl selling on here.

Thanks for the confirmation of the speed cut wire too nismoid.

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