Your truck is a square body so you posted in the wrong section of the board. It is a different body style then the trucks in this section and that may be why you are not getting more help.
You said you found a code 42, so you must have checked codes, and if it had a fuel relay problem it would have set a code 54.
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The distributor is only about a year and a half old. And the pick up coil? I wonder if that would keep from turning the pump on, cause the truck cranks but the pump wont turn on so its not getting fuel
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The distributor has no control connection to the fuel pump running or not, but ECM needs to receive a distributor reference pulse from the distributor module to trigger the injectors.
If the injectors are not spraying fuel it does not tell you there is no fuel pressure. The injectors may not be opening.
The ECM controls the fuel pump relay.
The truck has a fuel pump relay that supplies power to the fuel pump when:
- Anytime the ECM receives a distributor reference pulse. (Engine running / engine cranking)
- The key is turned on engine not cranking – relay applied for 2 to 20 seconds (most trucks 2 seconds), depending on emissions equipment. Trucks over 8500 GVW and some other vehicles have and electronic Fuel timer module that allows the pump to run up to 20 seconds.
The key must be turned off for a certain amount of time before it will prime the system again when turned back on.
There will only be power to the fuel pump for a few seconds when you first turn the key to the on position. If you are turning the key on then walking around the vehicle testing for voltage to the fuel pump circuit there will be no voltage and should not be power to the pump.
The ECM should store a code 54 if the fuel pump relay fails.
A code 42 is set when the ECM loses communication with the distributor.
Code 42 can be set by a bad distributor module, a bad ECM or wiring problems between the ECM and distributor.
A code 42 will get set when the set timing connector is unplugged to set the timing. Make sure you clear the codes after setting the timing.
A bad distributor module is a common cause for this code.
Many stores like NAPA in my area will test the module for free if you bring it in.
Make sure when you install or reinstall the distributor module that you use heat sink compound/grease under it. The grease helps dissipate heat from the module. Without it, the module will fail.
Here is a thread you may want to read:
http://67-72chevytrucks.com/vboard/s...d.php?t=495054
You may want to do a search and do some reading.
You need to find out if the truck has spark or not.
You need to see for sure if the fuel pump runs or not.
If the fuel pump does not run, you need to check it for a code 54.
CT