maverick9576

My wife got me a MAC stainless steel straight shot air system GT version for Christmas. I installed it in my 2005 mustang and it all went smoothly as this is a very simple install. Well after driving for a bit the check engine light came on. I checked all my clamps and the screws for the air flow sensor and tightened a bit and reset the check engine light. Well sure enough the light came back on after a few miles. I don't have a programmer yet so I took it to a parts store and had them check the codes. Basically I was getting 174 and 171 error. Meaning it is running lean. I would expect this to be the case if it is getting more air but I guess I kind of thought the internal computer would adjust for that. Do I need a programmer like the Diablo Predator to get around this check engine light problem. I plan on getting a programmer anyway but wanted to know if I might have another problem with the MAC that I installed.

Thanks

Rannascar

You need to get the Computer flashed... And Yes that means you need A Diablo Preditor or SCT ,,,, there are many products that you can use to adjust the fuel ratio mixture since adding a CAI. I would get it done asap so you can get the performance the cold air induction gives you. There maybe a speed shop in the area you live in that has a dyno they can flash it and re-calibrate for peak results...

kstob03

I've got a K&N CAI on mine and had the same problem. From everything I've read, you definitely do need a tune. I've got mine on the way from Brenspeed (delivery on Jan 4). I contacted K&N before I ordered the tuner though and they said to disconnect my negative battery cable for 1 hour. I've had no problems since and it's been over a month. One thing I noticed when I did this is that before I disconnected the cable and w/ the check engine light one I was getting 20.3 mpg. After the fix, it dropped to 19.5 mpg. Seems the cars computer adjusted just fine w/ only the CAI on. Definitely get a tune though.

maverick9576

Thanks for the responses. I guess I was pretty sure I needed the programmer but I was told by some people that I shouldn't need to flash from just installing a CAI. They told me the internal computer would adjust for the extra air coming in. I have ordered my diablo predator.

Thanks

SpikeGT

We can only wish it would be that simple, that the computer would adjust itself. The tune is very easy to install and you should be up and running in no time with a tuner.