Q: My car will not go over 20 mph.

asked by on December 23, 2016

A year ago I had this same issue. So I took it the mechanic and a new throttle body was installed that was on January 1st of this year. This morning I was going to work and my car had a rough moment during driving than would not go over 20mph. The codes read bank 1 fuel trim to rich. That's the same code from last time this happened. Now a year ago I installed in addition to a new throttle bottle new sensors and today I put in new spark plugs and a new lower radiator hose because it had a crack. And the car still wouldn't go over 20. So I stopped turned it off and started it back up and it ran fine but the light is still on. I can't figure out what to do anymore and I can't afford to keep just dumping money into this engine. Any idea of what it may be.

My car has 93567 miles.
My car has an automatic transmission.

Hi there. Check the fuel pressure regulator and make sure that its working and plugged in. Put a fuel pressure tester on the fuel rail and make sure that there is good fuel pressure of 45 to 65 psi. If the pressure is low, then there is an issue with the fuel pressure regulator, fuel filter, or fuel pump. Also, check all of the vacuum lines to the engine and make sure that they are tight and not cracked. Replace any vacuum lines that are broken, missing, cracked, or loose on the connections. Your vehicle is driving at only 20 mph for the computer has put the engine into limp mode. If you need further assistance with your loss of power, then seek out a professional, such as one from Your Mechanic, to help you.

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