Need Help 08 WRX sedan idle issues with Maf pluged in

[dimkaa]

People Need Help just bought 2008 Wrx sedan from an action, when i was done with it i decided to install a cold air intake when i did that the car was idling very low and shutting down inventively after driving, then i installed the regular stock intake box, when i connect the MAF sensor car idles very low the car shakes and after driving for about 15miles gives me 6 codes 2 for system to lean and 4 for cylinder misfire in all 4 cylinders when i unplug the MAF sensor car runs much better, i tried cleaning the sensor did not help don't know what to do, don't what to but the sensor before knowing that the sensor is the problem, cheapest sensor i found was 150$

[Dzanga]

You need a tune. You can't add intakes without the proper tune.

[SD_GR]

The sensor harness should face forward, with the wiring toward the nose of the car.

Since the car runs better without actual MAF data, either the intake is unsuitable or the MAF is not working correctly. Since the MAF was working before you installed the intake, that leaves us with a badly connected MAF, that you can fix, or a badly implemented intake, that you can also fix: install the correct intake again, install the MAF correctly as above, and forget about the intake until you decide to reflash the car -- if at all.

[dimkaa]

I installed the Stock intake back and i installed the MAf Sensor correctly but that did not fix the issue. When i installed the cold air intake i unplugged the battery for 30 minutes that did not fix the issue, so i installed the stock intake and unplugged the battery for 30 minutes also didn't fix the issue. is there a way to test the MAF sensor or i have to buy a new one and go from there?

[dimkaa]

I found this rewired harness for the MAF sensor on the car the big fat wire is not original and it goes all the way down inside the car im guessing to the ECU computer, i have no idea why this has being done has anyone seen anything like this and why its there, can this be the couse of my rough idle????

[Donkey]

It obviously has been done because there was damage to the harness/wire/car. Without you being able to test the wire or use an OBDII scanner to pull data from we are not going to able to help you. Buying cars from auctions is generally a bad idea if you are not mechanically auto savy with current OBDII cars. Could it be the source of your problem? Absolutely. But that why you troubleshoot by testing/verifying operation function. That way you don't guess it is your problem,you know it is or is not.

[dimkaa]

Well first off the car had extremely light damage no frame or any mechanical damage done to it, second i do have the OBD tool and i have the codes that came up like i said in my previous add P0171 bank 1 2 codes system to lean, and 4 P0301,P0302,P0303,P0304 cylinder miss fire detected. And another thing only 2 wires were rewired so that means the harness is the original one what my question is why is it that all wires are original at the fat one is not and weather that as an issues at all????

[Donkey]

Well first off the car had extremely light damage no frame or any mechanical damage done to it, second i do have the OBD tool and i have the codes that came up like i said in my previous add P0171 bank 1 2 codes system to lean, and 4 P0301,P0302,P0303,P0304 cylinder miss fire detected.

A scanner can do more than just read codes. It will allow you to look at things like MAF voltage,airflow g/s,AF learning and a ton more.

And another thing only 2 wires were rewired so that means the harness is the original one what my question is why is it that all wires are original at the fat one is not and weather that as an issues at all????

I didn't say it wasn't original. I said it was damaged. Why else would someone try to repair it? That is why there is a different wire attached. That should be extremely obvious. We won't know if it's the issue if you don't test the MAF and the wires to verify proper operation. That is how you troubleshoot a problem. We don't have the car in front of us. We can speculate and guess all day long.