2008 subaru legacy problem

Asked by May 21, 2016 at 09:30 PM about the 2008 Subaru Legacy 2.5 i Special Edition

Question type: Maintenance & Repair

So I recently put in an cold air intake and my vehicle was
driving well at first butime  then I started to notice it was
loosing throttle response. I took it home and turned it off,
then turned it back on and tried to reverse and it starts
jerking and the rpms were bouncing. It does the same when
I put it in drive! So I eventually backed out of my drive way
but the car only let's me accelerate to 20 mph or lower. Im
not sure what to do. I've pulled a code  p2109. The car
sounds bad when I idles. Idk can someone help?

7 Answers


P2109 - (ASE) DTC Description: Throttle / Pedal Position (Sensor A) Minimum Stop Performance. Recheck your work, sounds like something isn;t hooked up properly. Do you have an oil filter installed with the intake, like a K&N? Sometimes they are over oiled and the oil contaminates the elements on the MAF.

Best Answer Mark helpful

How was it working BEFORE you did this and WHY did you do it?? What were you trying to achieve?


How many miles do you have on your 2008 Legacy?

So Ive recheck everything all connection are secure. I checked the MAF and cleaned it. Nothing changed. Could it be the throttle sensor? Also my cars mileage is 53,000


Hmm,. 53,000 miles?? I wonder why you're having so many issues? Did you really get more performance with the modifications?? And, how much?


What else did you replace besides the duct/piping? A new MAF? remove any plugs? Take off the throttle body or TPS?


Try installing the OEM stuff back on and see if you still have a problem?

Your Answer


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