Thank you for your response.
I have done the following in order to resolve this problem:
1. Installed a fuel pressure and flow test port in the steel fuel line immediately after the fuel filter with a steel Schrader Valve to connect the fuel pressure test gauge.
2. I have then used an Innova fuel pressure test gauge to test the fuel pressure. The following are the results of the test for the vehicle in question:
2.1. Fuel Pressure with Engine Running: 425.0 kPa (65.0 psi approximately).
2.2. Fuel Pressure with Engine Off and Ignition On: Same as above.
2.3. Fuel Pressure with Ignition Off: 400.0 kPa (58.0 psi approximately).
2.4. Fuel Flow Rate as measured through the discharge port of the Innova fuel pressure test gauge with Engine Off and Ignition On: 0.250 litres per minute.
2.5.1. The fuel pump continues to run with the Engine Off and the Ignition On but it stops for less than a second and then runs again for about 5 seconds and repeats this cycle over and over again as long as the ignition is on.
2.5.2. The results of the pressure test indicate that the pressure readings are within the specifications as contained in the original Daimler Chrysler manual which are as follows: 400.0 + or - 34.0 kPa (58.0 psi + or - 7.0 psi).
2.5.3. There is no specification in the manual for the fuel flow rate.
3. I then tested the ASD (Auto Shut Down Relay) by switching it with another identical relay. This did not solve the problem of the engine shutting down after running for random intervals of time. These times vary between 5 minutes and 90 minutes or more with the engine idling.
Some history might help. I have never had this problem with this vehicle and the vehicle has been running reliably for 14 years with only routine maintenance. It has close to 400 000 km on it. This problem started after I took the vehicle for emission test repairs to a very large and leading repair establishment for carrying out emission system repairs required by the Department of Transportation. Just before I took it for the repairs, I had driven the vehicle from one city to another for a distance of 650 km WITHOUT ANY PROBLEM.
I now await your expert opinion on the causes for the random shutting down of the engine.
Tuesday, August 28th, 2018 AT 10:07 AM