'79CA bus intermittantly wont start, fuel pump not triggered
Posted: Fri Jan 03, 2014 1:15 pm
On my summer project bus, also a 79 California import, ive ran into this problem 4 or 5 times now.
Symptom - it won't start.
I leave the key in the ignition, go back and pop the lid off of the AFM and move the swiper - you can hear a very distinct 'CLICK' - but no fuel pressure is seen.
The first few times I simply unplugged both connections to the double relay, plugged them back in snugly, wiggled the little ground wire that grounds to the double relay mounting screw, and fuel pressure returned.
On new years day, at around 3:30AM of course, it pulled this on me again. This time the old trick didn't work. I started to fiddle around trying to find where all of the wires to/from the relay are going - and at some point I wiggled the cluster of wires heading back through the firewall towards the fuel pump and it worked - for just a second. I couldn't repeat this.
Next I crawled under the bus to check the wiring at the pump itself. I have a barely lit flashlight (and mind) at this point, but im just feeling to see if the two wires going to the fuel pump are still connected snugly. I try also to just track where the wires are coming/going, to see if anything is obviously split/broken/whatever - but for the most part I just touch everything and give it a little wiggle. Nothing seemed obviously out of place.
After this last attempt under the bus at the fuel pump, now it starts right up and I again have fuel pressure.
With it only happening intermittently, I am not sure how to move forward with preventing this in the future. Should I just re-do the wiring at the fuel pump? Is this a sign the double relay is *starting* to fail? When it's working, which is 99.9% of the time, it'll pass all of the tests (right?)
I just don't want it to happen in an inconvenient time/place, like 3:30AM on new years day in a shitty neighborhood with all of my expensive Dj gear sitting inside (as an example.)
Symptom - it won't start.
I leave the key in the ignition, go back and pop the lid off of the AFM and move the swiper - you can hear a very distinct 'CLICK' - but no fuel pressure is seen.
The first few times I simply unplugged both connections to the double relay, plugged them back in snugly, wiggled the little ground wire that grounds to the double relay mounting screw, and fuel pressure returned.
On new years day, at around 3:30AM of course, it pulled this on me again. This time the old trick didn't work. I started to fiddle around trying to find where all of the wires to/from the relay are going - and at some point I wiggled the cluster of wires heading back through the firewall towards the fuel pump and it worked - for just a second. I couldn't repeat this.
Next I crawled under the bus to check the wiring at the pump itself. I have a barely lit flashlight (and mind) at this point, but im just feeling to see if the two wires going to the fuel pump are still connected snugly. I try also to just track where the wires are coming/going, to see if anything is obviously split/broken/whatever - but for the most part I just touch everything and give it a little wiggle. Nothing seemed obviously out of place.
After this last attempt under the bus at the fuel pump, now it starts right up and I again have fuel pressure.
With it only happening intermittently, I am not sure how to move forward with preventing this in the future. Should I just re-do the wiring at the fuel pump? Is this a sign the double relay is *starting* to fail? When it's working, which is 99.9% of the time, it'll pass all of the tests (right?)
I just don't want it to happen in an inconvenient time/place, like 3:30AM on new years day in a shitty neighborhood with all of my expensive Dj gear sitting inside (as an example.)