I have a jeep grand cherokee and it does not start right away when cold. I have replaced the fuel filter, pump, and pressure regulator valve. You have to floor the gas pedal to start the vehicle???

Your Jeep has what's known as the delayed start, no check engine light problem. The Jeep will not start until the check engine light comes on, on the dashboard. Next time it cranks but will not start, look at the dashboard to see if the check engine light is illuminated. If it's not lit up, then your Jeep does have that problem and your Jeep ecu is in need of repair or replacement. There are components inside the ecu that are going bad and will continue to get worse, eventually leading to a permanent no start condition. There are ecu repair services and replacement ecus on ebay.

check fuel pressure regulator.....Fuel on one side of diaphrag, and vacuum pressure on other if there is fuel on the vacuum side then diaphragm is leaking...causing ecu to think there is plenty of pressure and holds back the signal to turn on fuel pump....

1998 Jeep Grand Cherokee 4WD 5.2L MFI 8cyl the Fuel Filter is part of the fuel pressure regulator assembly which is located on the fuel pump module.The fuel pump module is located on top of the fuel tank.


Hope this helps (remember to rate this answer).

For 2000 Jeep Grand Cherokee the Fuel Filter is located under vehicle, driver side, below bed area, front of fuel tank, mounted on chassis in fuel line.



Fig. Fuel filter/pressure regulator location-1999-01 models







Fig. Fuel filter/pressure regulator-Grand Cherokee

1. Before servicing the vehicle, please familiarize yourself with safety procedures.
2. Relieve the fuel system pressure.
3. Remove or disconnect the following:
   Negative battery cable Fuel supply, return and pressure lines Mounting bolts Fuel filter/pressure regulator

To install:

1. Install or connect the following:
   Fuel filter/pressure regulator to the body. Torque the bolts to 30 inch lbs. (3 Nm). Fuel pressure, return and supply lines Negative battery cable
2. Start the vehicle, check for leaks and repair if necessary.

Gooe luck (remember rated this post).

change the auto choke temperature sensor

You may have one along frame rail near rear wheel area on drivers side.

Also check the vaccum hose from the fuel pressure regulator to the intake manifold, it is right on top, to the front right of the valve cover where the fuel lines attach to the fuel rail, there is a small vaccum hose that runs from the regulator to the intake manifold, I have a 93 grand cherokee limited w/ 4.0L 6cyl, it was hard to start at times, wouldnt start at times without starting fluid spray and had your symptoms at idle, running rough like it wanted to stall like it was out of gas, I had various opinions ranging from fuel pump was bad to the fuel filter to the fuel presure regulator, the fuel pump relay ,etc....after replacing the relay and having the same symptoms, some digging brought me to this vaccum hose, wich had a break in it, when it was replaced it allowed the regulator to have the correct fuel pressure output and solved all the afforementioned problems way cheaper than the suggested alternitives. good luck.

On a 4.0, 40psi is OK cranking...it should drop about 10lbs running . If not check regulator. Also do a drainback test. often the check valve in the pump fails requiring that system reach pressure before it can start.
Also check fuel delivery. if filter is partially plugged pressure may be OK but fuel flow will not be.

Could be a sensor.I'm thinking more along the lines of a fuel pump or fuel filter.If the fuel pump is going bad..similar symptoms.Would be advisable to install a pressure gauge at the engine,and check fuel pressure when it's acting up.