my car stalls and can’t find the solution

denniskobylnik

hey guys I have a serious problem. So currently I have an automatic 2010 Subaru Impreza 2.5i and right now the car is stalling when the car is parked and has warmed up. I checked the codes and I got the “cylinder 1 and 2 misfire” code and the guys at the auto shop told me to start by changing the spark plugs, and so I started by first switching the sides of the coils, and the same code came up and so I knew that the problem wasn’t in the coils, and so I changed the spark plugs. I then checked again and the code for the oxygen sensor came up and so I then changed the mass airflow sensor, and finally i checked back again and I got the “catalyst fuel efficiency below threshold bank 1” code and so I started by changing the fuel injectors, then the cat sensors both upstream and downstream and finally the cat itself. The problem wasn’t fixed, there’s clear smoke coming from the exhaust, the fuel doesn’t fully combust, the gas smells with a mix of burning plastic and unburnt fuel as if you were standing in a running boat, and when you put the car into drive or reverse, the car shakes and has a high pitch sound as if you were to shake a can of spray or something. Any help is appreciated. 

93tracker5spd

Hello, what catches my eye when reading your post is that the code for the oxygen sensor came up, but you changed the mass air flow sensor. The problem sounds like the fuel air mix is to rich, "getting to much fuel in the mix", and the oxygen sensor malfunctioning would certainly cause this. If that was the case and not a type-o I would re-visit the oxygen sensor, test it and see if the problem is there. Good luck!

Mr_Shiftright

Glad to hear you solved it. This is a good case for not assuming that the trouble codes tell you which component is faulty. They don't. They can only tell you which systems are in distress, but often cannot pinpoint exactly why. This is where a good technician comes into play, who can use his more sophisticated scanning tools to track down what's going on "in real time" as it is happening.

denniskobylnik

Yea thanks man! Well apparently we fixed the problem. It was the ignition coils. But its not your usual coils where it’s on every individual cable, all the coils are in one unit and the cables run from the unit to the spark plugs. But thanks so much for your input. I’ll be sure to keep it in mind the next time I have a similar problem.