I have codes P0303, P0304, and P0136. Swapped out the coil pack and plug wires are fairly new, any thoughts, igniter? A few times the CEL would flash as I was driving but the car ran fine. On the P0136, that's the post cat O2 sensor, right? There was a small section of the exhaust I removed right after the cat and sensor (looked like a very slim resonator and not long), I put a piece of pipe in there, wonder if that's the cause, the car runs fine.

the p0136 is probably because you are not burning all your fuel.

fix the misfires first.

 

yes the igniter.

it feeds the coil in the same front / rear way the coil feeds the plugs.

thanks, I think I have a spare igniter somewhere, i'll start there, common sense fix upstream problems first and as you say it could very well take care of the other

well, it's not the igniter, this trouble code just doesn't turn the CEL on, it flashes it, got a coil pack here

There is an ignitor module on the firewall dead center above the trans mount.

P0136 = O2 circuit sensor 2

 

This code would be for the rear sensor, no it would not be affected or caused by the resonator pipe. More than likely caused by a dead sensor or damaged wiring to the sensor.

This sensor does not affect fuel economy or engine running condition, it is only a check sensor for the catalytic converters.

when i read my owners manual, i forget which year, it said

a flashing CEL meant there was a condition that could damage the catalytic converter,

like unburnt fuel, maybe.

 

any way, that is my understanding of a flashing CEL.

Edited October 18, 201312 yr by johnceggleston

flashing CEL is universal with the OBD II system not just Subaru and it does mean that the catalytic converter will be damaged with continued driving. Usually caused by a missfire which will almost always make a CEL flash at least a few times.

Edited October 18, 201312 yr by matt167

Try a hp feul pump having lots with low feul preshure ishues a Carter P74152HP pump is 260 lpr vs the stock 160 lpr have fix to misfire cars with this part in last week

thanks for all the good info, the igniter and coil pack has been changed out, took out and replaced plug 3, but plug 4 comes out real tough and I thought I may be damaging the threads so i turned it back in, it is firing though, the trouble codes are 0303 and 0304. I can't get an inspection sticker with a lit CEL so I'll clear it when I pull in and hope it stays out...lol

now looking to fuel delivery issue, or I may fix this issue with a 1" x 1" piece of black tape, anyone now what pin on the ecu turns on the CEL