I’m so lost! Please help!
#1
I’m so lost! Please help!
I have an 03 Dodge Dakota 3.9, 149k. Has a rough idle and sometimes drops below 500 rpm’s. Changed out intake manifold gasket, throttlebody gasket, Repaired all vacuum leaks, plugs wires, distributor, MAF, TPS, IAC, all four O2 sensors, camshaft positioning sensor, crank sensor, temp sensor, all fuel injectors and O-rings, and a few other things. Compression on all cylinders is between 130, and 140. Fuel pressure is at 95psi. Still have code P0171 and P0174 with a rough idle, and fuel doesn’t last while driving due to consumption. Scan tool says STFT on both banks are roughly between -3 and 5. LTFT on both banks is constant at 32.
Last edited by Josh850; 01-20-2020 at 10:33 AM.
#4
I have an 03 Dodge Dakota 3.9, 149k. Has a rough idle and sometimes drops below 500 rpm’s. Changed out intake manifold gasket, throttlebody gasket, Repaired all vacuum leaks, plugs wires, distributor, MAF, TPS, IAC, all four O2 sensors, camshaft positioning sensor, crank sensor, temp sensor, all fuel injectors and O-rings, and a few other things. Compression on all cylinders is between 130, and 140. Fuel pressure is at 95psi. Still have code P0171 and P0174 with a rough idle, and fuel doesn’t last while driving due to consumption. Scan tool says STFT on both banks are roughly between -3 and 5. LTFT on both banks is constant at 32.
The following users liked this post:
Josh850 (01-23-2020)
#5
This is out of the 2000 service manual
FUEL PUMP PRESSURE TEST
(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 (Fig. 8). The DRB III Scan Tool along
with the PEP module, the 500 psi pressure
transducer, and the transducer-to-test port
adapter may also be used in place of the fuel
pressure gauge.
(2) Start and warm engine and note pressure
gauge reading. Fuel pressure should be 339 kPa 6 34
kPa (49.2 psi 6 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.
(5) Install protective cap to fuel rail test port.
FUEL PUMP PRESSURE TEST
(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 (Fig. 8). The DRB III Scan Tool along
with the PEP module, the 500 psi pressure
transducer, and the transducer-to-test port
adapter may also be used in place of the fuel
pressure gauge.
(2) Start and warm engine and note pressure
gauge reading. Fuel pressure should be 339 kPa 6 34
kPa (49.2 psi 6 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.
(5) Install protective cap to fuel rail test port.
The following users liked this post:
Josh850 (01-23-2020)
#7