I tried to pass a truck on the interstate. When I hit the gas the car bogged down. After that, the car ran fine at cruising speed but hesitated when I accelerated. Then it started dying. I can crank it but it won't stay running unless I pump the gas. I've replaced the spark plugs, wires and ignition coils. I think it may be the catalytic converter or the fuel pump. I tested the fuel pressure. It reads 48 lb psi. The spec for my engine is between 53 and 58 lb psi. The car is not throwing any codes. I have not replaced any sensors (IAC, MAF, TPS, etc) nor have I replaced the injectors. Any idea?
My car has 170000 miles.
My car has an automatic transmission.
There happens to be two different fuel pressure specs depending on your VIN number if it has a 1 or a K for the 8th digit. The spec for the 1 is 48 to 54 psi and if yours is a K then it is 53 to 59 psi. If yours is a K then the low pressure may be the issue and replacing the fuel pump may repair the problem. Try disconnecting the fuel pressure regulator at idle to see what the pressure goes up to? If the pressure goes to 54 psi then I think your pressure is okay and need to remove and check the fuel filter for blockage and replace it and see if problem goes away. If the problem still exists after this, then I suggest having a qualified technician, such as one available from YourMechanic, diagnose your running issue.
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