Hello - I'm getting P0302 with traction control light and flashing check engine light and the car is running rough, the misfire is apparent and I can see the car engine shaking a tad bit more than usual. I swapped the coil and spark plug to see if the code changes with the coil swap but no. I also see FUELSYS1 OL_Fault and FUELSYS2 OL_Fault, not sure what that means. What could be the issue ? Any help is greatly appreciated. Thank you.

OL=Open Loop

The PCM is seeing issues with fuel delivery while it is in open loop.

What is the fuel pressure?

What did the spark plug look like?

How many miles on the car?

How many miles have you owned the car?

How many miles does it usually go between oil changes?

Fix the misfire first. That may take care of the open loop problem as well. Does that scan tool do ABS? Need to see what that module is coding. Likely a wheel speed sensor.

What is the fuel pressure?
When I connected the gauge to the shrader valve and put the key in the ON postion it read at 23 PSI and when i started the car it climed to 59 PSI and when I switched off and on again it was at 59 PSI.






What did the spark plug look like?




How many miles on the car?
It has 110604 miles ( 178,000 km)

How many miles have you owned the car?
I have owned the car since 85749 miles ( 138,000 km)

How many miles does it usually go between oil changes?
5000 miles

No, the tools doesn't do ABS. The tracking light comes on as soon as the check engine light start blinking. I've had issues with traction control system and I did replace the abs wiring harness few months ago even then I had only ABS light never the check engine light.

Here is the sound of the car, it seems off. I'm wondering if valve spring broke.

Okay, fuel pressure looks good. 110,604 miles (178,000km) is 10,604 miles (17,605km) overdue for replacement spark plugs. Definitely replace them, might solve the problem. Can't tell from the picture how eroded the spark plug is. Don't go cheap on these spark plugs.

If you think you might have other issues, maybe now is the time to do a full compression test while you are already taking every spark plug out anyways. From your recording, I wouldn't worry about doing a compression test yet. (more on this when I get to that post)

Is your oil change interval before every 5,000 miles or when it hits 5,000 you get around to it later like more than 500 miles later? . . . or somewhere in-between?

If the misfire is bad enough, it will disable traction control for that drive cycle.

This sounds like a miss, possibly with an aftermarket loud exhaust? . . . but I don't hear evidence of a bad valve spring.

These engines aren't known for bad valve springs for what it'* worth.

The spark plugs were replaced at 140,000 km with NGK iridium plugs so I've been running these plugs for about 38,000 km. I usually do change the oil mostly before 5000 miles because I run walmart High mileage oil(I read in forums where people recommended to change walmart oil before 5000 miles).