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2013 GT500 After intake installation understanding air to fuel reading


Mod GT500

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After installing my K&N intake with no tune I started to take notice of my air/fuel reading at idle my reading is mostly at 14.1 but fluctuates down to around 13.1 and back up. At WOT it goes down to 11z and then shoots up all the way to 20 and back down to steady 14z as I let go of the gas. Is this normal or ok ? Just curious because I like to really understand the details of how my car is running and I'm trying to avoid the stock intake back on just to compare.

 

Also I just started to realize when pulling up and stop at a traffic light my rpm goes down to 1000 and stays there for a sec before going lower to idle did not notice this before

 

Third for some reason all of the sudden on normal acceleration from 0 on first gear it feels like my rpm climbs slower up to 2500 and then picks up where is before it would shoot up from start, there for I would get that power launch feeling with out having to rev it before launching

 

Could it be I have an air leak somewhere ?

 

Any clarification on these concerns Would be greatly appreciated

 

I'm sure it could be nothing and maybe I'm just exaggerating but its still good to know

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The air/fuel mixture gages for me are about worthless. The fluctuate wildly and distract from driving. The only way to be certain is to have the car monitored on a Dyno. I cant see a filter change from the stock to a K&N doing a whole lot but, I can see it leaning the car out a little. Im no expert so others may chime in but a good tune is in order or, return to stock.

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I cant see a filter change from the stock to a K&N doing a whole lot but, I can see it leaning the car out a little. Im no expert so others may chime in but a good tune is in order or, return to stock.

 

 

Naw, a filter change won't lean it out. IF it allows more air through it the MAF sensor will see it, tell the PCM there's more air entering the engine and the PCM will add fuel to compensate for it (thereby giving you more POWER).

 

That is on a OEM tune or on a tune performed by someone trained to tune it right (see below).

 

Some of the aftermarket tunes don't allow for mods without a retune due to the method they use to tune with (SCT taught). For instance, on my car with a Ford Racing tune, I added headers and a open exhaust without any need for tuning. Ask your tuner if you can add headers/open exhaust without a tune and you will know if they used the SCT method (tweaking the MAF instead of cells in the look-up graph) or not.

 

 

Phill

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I read that cold air you should do a tone ??????

 

 

Only if it includes a larger MAF sensor housing.

 

If all you're doing is opening up the air box and putting a 'high flow' filter element (such as a K&N) on the intake (pre-MAF), there's no need to do a tune, provided it's a OEM tune or a tune performed the right way.

 

 

Phill

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