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K. Wiggins
K. Wiggins, ASE Certified Technician
Category: Lexus
Satisfied Customers: 2911
Experience:  ASE Certified Technician, Associates Degree in Automotive Technology, 15+ years in the trade
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When driving and when I press the gas pedal hard the engine

Customer Question

When driving and when I press the gas pedal hard the engine will start to accelerate then will start to sputter or just sit at a certain rpm.
Submitted: 1 year ago.
Category: Lexus
Expert:  K. Wiggins replied 1 year ago.

Hello, is the check engine light on and if so have you had the codes pulled?

Customer: replied 1 year ago.
check engine is not on
Expert:  K. Wiggins replied 1 year ago.

Thanks, ***** ***** to look at are

1. Fuel pressure

2. Restricted exhaust (catalytic converter can clog)

If you could give me the year, model and engine size I'll pull the fuel pressure specs for you.

Customer: replied 1 year ago.
1992 Lexus sc400. New fuel filter and fuel pump. If the car is in park and I rev the motor it doesn't have any problems. When I'm driving and try to accelerate it ask like it doesn't want to shift but also sputters. At low accelerations I don't have the problem but if Im trying to climb a hill the rpms will climb to close to 4000 and start to sputter.
Expert:  K. Wiggins replied 1 year ago.

The acting liek it doesn't want to shift and sputtering under load but reving fine does sound more like an exhaust restriction. You can either drop the down pipe some or remove the oxygen sensors to see if that's the issue.

I'll post below on how to chck the fuel pressure and regulator, as a bad pressure regulator can cause this as well