Hi Everyone,
I have a 2006 (2007 US Model year) Honda Jazz (Fit) with the L15A1 motor with 250000Kms (156250 miles). I am experiencing a very slight miss under load (Check engine light not tripped). I have a super basic scanning app and have also noticed that my fuel trims indicate the car is running rich. My plan was to check the fuel pressure and then injectors if the fuel pressure regulator seemed fine.
Could the above be caused by carbon build-up? I did adjust the valves recently so I don't think it is that, but I'm happy to have another look there if that could be the issue.
Any assistance or advice would be greatly appreciated.
Thanks in advance,
Graham.
Did you check the air filter?
A clogged filter will prevent the engine from getting enough air, making it run rich and reducing overall mileage.
You could also check if the throttle is dirty.
@udyr
Thanks - the filter was changed within the last year, and with COVID it hasn't done much mileage. I have checked it and it is clean. When I last did the valve adjustment I did clean out the throttle body that was quite dirty. I also went through the process of performing an idle relearn.