So happy to hear there are still Stream owners with more than 10 years of usage.
I seek everyone's opinion on my current issue on my 11-year-old Stream. I'm having random cylinder misfires (Codes P300, P301, P302, P303 and P304). I understand that those codes ending with 1, 2, 3 and 4 corresponds to each individual cylinders. I read up that misfires are usually caused by either electrical issues for sparking (coil, plugs or both), fuel-related problems (pump, regulator, injector) or breathability (air intakes and exhaust, MAP, MAF, EGR, PCV, EGR). My car is in stock condition, no modifications made. The current mileage is about 325,000 km.
In the beginning, the code will surface during drives, especially when I did a hard acceleration then released of accelerator. It was torturous driving at North-South Highway with all 6 of us in the car and having the engine light blinking and feeling the misfiring engine every 5 minutes of driving at speeds of 120km/h. However, the misfire would not happen at that time if I drove at 110km/h and below, and was gentle with accelerating.
The error codes will also surface if I'm on stationary, on parked or neutral gear, and I hold the accelerator to a steady rpm reading of 2000 rpm, 2500 rpm, 3000 rpm or 3500 rpm.
I've been troubleshooting it for the past few months, and have changed the following:
1) all 4 ignition coils
2) Denso Iridium plugs IK20L
3) all 4 injectors
4) MAP and MAF sensors
5) camshaft and crankshaft sensors
6) EGR valve
7) 2nd hand catalytic converters (though there was no clear signs of honeycomb melting after so many misfires, I wanted to play safe and get it replaced anyway.)
Air-fuel sensor (wide-band O2 sensor, before CAT)
9) 2nd hand Lambda sensor, very hard to find brand new one (O2 sensor after CAT)
10) fuel pump
11) both coolant engine temperature sensors (one near thermostat, one at bottom of radiator)
13) knock sensor (after my mechanic and I found out my spark advance at idle was always negative during idle. It got back to normal at above 0 degrees after replacing it)
I'm still waiting for my fuel regulator to arrive. At the moment, all symptoms have gone except when I hold the accelerators at stationary. Because of this issue, I'm also unable to make the car relearn the idle after reset.
My short term fuel trim (STFT) and long term fuel trim (LTFT) has been negative at idle and driving. At idle, it can reach a low of about -7%. At driving, it can go at about -3.1%. I've also read up that ideally such readings should reach 0%, and we should be concerned if the fuel trim reaches either above +10% or below -10%.
I hope that my car will be back to normal after the fuel regulator is replaced.
Any advice is greatly appreciated!
Thank you for reading such a long post.