Engine stutters when decelerating

Hi,

I don't think it's a transmission issue or related to the parking brake. Is the check engine light on and staying on when the engine is running? If there was an engine misfire, the light should be on. Also, weak fuel pressure can cause what you described as well.

If the check engine light is staying on, here is a quick video showing how to scan the computer to retrieve diagnostic trouble codes.

https://youtu.be/YV3TRZwer8k

I realize most people don't own a scanner, but often times, a parts store will do it free of charge.

If the light isn't on, let me know.

Take care, and congrats on graduating!!! Nice pic.

Joe

Hi,

Here is a link that explains in general how it's done:

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

Here are the directions specific to your vehicle. They include the manufacturer's specs. You will need a fuel pressure gauge. However, most parts stores will lend or rent one to you. The attached pic correlates with the directions.

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1999 Dodge or Ram Truck RAM 1500 Truck 4WD V8-5.9L VIN Z LDC
Fuel Pressure Test - With Test Port
Vehicle Powertrain Management Fuel Delivery and Air Induction Fuel Pump Fuel Pressure Testing and Inspection Component Tests and General Diagnostics Fuel Pressure Test - With Test Port
FUEL PRESSURE TEST - WITH TEST PORT
Use this test in conjunction with the Fuel Pump Capacity Test, Fuel Pressure Leak Down Test and Fuel Pump Amperage Test found elsewhere.

Check Valve Operation: The electric fuel pump outlet contains a one-way check valve to prevent fuel flow back into the tank and to maintain fuel supply line pressure (engine warm) when pump is not operational. It is also used to keep the fuel supply line full of gasoline when pump is not operational. After the vehicle has cooled down, fuel pressure may drop to 0 psi (cold fluid contracts), but liquid gasoline will remain in fuel supply line between the check valve and fuel injectors. Fuel pressure that has dropped to 0 psi on a cooled down vehicle (engine off) is a normal condition. When the electric fuel pump is activated, fuel pressure should immediately (1-2 seconds) rise to specification.
All fuel systems are equipped with a fuel tank module mounted, combination fuel filter/fuel pressure regulator. The fuel pressure regulator is not controlled by engine vacuum.

WARNING: THE FUEL SYSTEM IS UNDER CONSTANT FUEL PRESSURE EVEN WITH THE ENGINE OFF. BEFORE DISCONNECTING FUEL LINE AT FUEL RAIL, THIS PRESSURE MUST BE RELEASED. REFER TO THE FUEL SYSTEM PRESSURE RELEASE PROCEDURE.

Fuel Pressure Test Gauge (Typical Gauge Installation At Test Port)

Pic 1

1. Remove protective cap at fuel rail test port. Connect the 0-414 kPa (0-60 psi) fuel pressure gauge (from gauge set 5069) to test port pressure fitting on fuel rail.
2. Start and warm engine and note pressure gauge reading. Fuel pressure should be 339 kPa ± 34 kPa (49.2 psi ± 5 psi) at idle.
3. If engine runs, but pressure is below 44.2 psi, check for a kinked fuel supply line somewhere between fuel rail and fuel pump module. If line is not kinked, but specifications for either the Fuel Pump Capacity, Fuel Pump Amperage or Fuel Pressure Leak Down Tests were not met, replace fuel pump module assembly. Refer to Fuel Pump Module Removal/Installation.
4. If operating pressure is above 54.2 psi, electric fuel pump is OK, but fuel pressure regulator is defective. Replace fuel filter/fuel pressure regulator. Refer to Fuel Filter/Fuel Pressure Regulator Removal/Installation for more information.

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Let me know what you find or if you have other questions.

Take care,
Joe