I've been trying, and failing, to get my car car to pass emissions. Had a state diagnostic done for free, they said the fuel pressure is too high. It should be around 66 but bounces around 80. Have sense replaced the mass airflow sensor, o2 sensors, fuel pressure regulator, air and fuel filter. Car runs better (better gas mileage, better rpms with acceleration) after replacing the MAF, but the fuel pressure is still too high. The engine doesn't make any unusual noises that I've noticed. Prior to replacing the MAF I would smell a hint of gas after starting the vehicle, but I haven't noticed it sense the new one went in. Any ideas at what I should look at?
My car has 170000 miles.
My car has an automatic transmission.
Hi there - the fuel pressure regulator on your truck has a vacuum-controlled adjustment which accounts for engine load. It’s possible that the vacuum source to the fuel pressure regulator is not functioning correctly, allowing fuel pressure to exceed the normal operating pressure. Check also for kinked or blocked fuel return lines to the fuel tank. I would recommend a fuel system inspection by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.
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