Loss of power

2010 MAZDA 3
167,000 MILES • 2.0L • 4 CYL • 2WD • MANUAL
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BENFOG02
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  • 1 POST
When I accelerate at full throttle, there is power, but when I hit a certain rpm, the power drops significantly. Between 4,000 rpm's and 5,500 rpm's, it feels like the car only has half its power, then at 5,500 rpm's, the power is back to full. Any idea what this could be? Video below.
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Nov 7, 2020 at 3:03 AM
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ASEMASTER6371
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Good morning,

I would check the fuel pressure first to be sure the pressure is correct.

https://www.2carpros.com/articles/engine-has-low-power-output

It could be a restricted fuel filter. The issue is the filter id part of the fuel pump.

No External Fuel Filter For Service, High Pressure Filter Part of Fuel Pump Unit

https://www.2carpros.com/articles/how-a-fuel-pump-works

https://www.2carpros.com/articles/how-to-replace-an-electric-fuel-pump

Another possibility is injectors. They may need to be professionally cleaned. Additives have no effect on cleaning the pindles.

Roy

FUEL PUMP UNIT REMOVAL/INSTALLATION [LF, L5]

WARNING:
Fuel is very flammable liquid. If fuel spills or leaks from the pressurized fuel system, it will cause serious injury or death and facility breakage. Fuel can also irritate skin and eyes. To prevent this, always complete the "Fuel Line Safety Procedure", while referring to "BEFORE SERVICE PRECAUTION".
Fuel is very flammable liquid. If fuel spills or leaks from the pressurized fuel system, it will cause serious injury or death and facility breakage. Fuel can also irritate skin and eyes. To prevent this, before performing the fuel pump unit removal/installation, always complete the "Fuel Leak Inspection After Fuel Pump Unit Installation".

1. Complete the "BEFORE SERVICE PRECAUTION". See: Fuel Delivery and Air Induction > Vehicle Damage Warnings > Before Service Precaution

2. Remove the battery cover. See: Battery > Removal and Replacement

3. Disconnect the negative battery cable. See: Battery > Removal and Replacement

4. Remove the rear seat cushion. See: Seat Cushion > Overhaul > Rear Seat Cushion Removal/Installation

5. Remove the service hole cover.


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6. Disconnect the fuel pump unit connector.

7. Disconnect the joint hose of fuel-filler pipe side.

8. Disconnect the breather hose of fuel-filler pipe side.

9. Remove the following parts as a single unit.

Fuel tank
Joint hose
Breather hose
Fuel pump unit
Fuel hose

10. Remove the order indicated in the table.
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Nov 7, 2020 at 4:10 AM