The dreaded P0303 - new purchase & unknown mods
Just bought an 07' WRX. 54k Miles - front end accident history. Unfortunately the previous owner didn't know much about the car. I can see a short ram intake of some kind and some sort of intercooler kit (has Mishimoto hoses). If you see anything else besides that and the grounding kit - let me know. This could be caused by unknown injector sizes or other unknown mods. The only symptom I have is some overall hesitation throughout the whole power band, doesn't feel as strong as it should, but then again I have only once driven a stock 07 from the dealers lot.
Since I bought it...
Has a new complete OEM pump assembly (had low fuel pressure), new MAF (last one mysteriously read %20 compensations causing the engine to run rich (dealer told me when they fixed it)). If you want more details on that fix check out my first post:
New '07 WRX Owner
The dealer also told me plugs were replaced about 20 000 miles ago, and the ECU has been flashed of any possible tunes that may have existed.
I read through this:
IF YOU HAVE A MISFIRE CODE ,PLEASE READ THIS!!!
Before I start trying all of these things and spending buckets of cash...I was wondering if you guys have any ideas or suggestions as to what the issue is? I will use this post to log this issue fix to help others in the future. If you think this is lack of ECU tuning issue or unknown engine mod issue, let me know, otherwise I will troubleshoot the car as per OEM spec.
Next thing I'm gonna try is cleaning the injectors with Seafoam first, then Lucas upper cylinder cleaner with some long highway drives.
Check engine light + flashing cruise control light
Fuel sys 1: CL
Fuel sys 2: CL - fault
Calc load(%): 16.47
STFT B1(%): -10.94
LTFT B1(%): -3.91
Eng PRM: 2794
Veh Speed(mph): 13
Spark Adv(degrees): 51.00
Air Status: UPS
O2S B1 S2(V): 0.00
O2S B1 S2(V): 0.00
Let me know your thoughts on what the next step should be.