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JonRoss
10-03-2012, 01:41 PM
Hey Vanlovers!
I'm having issues getting my van to start. Went through a ton of electrical troubleshooting - relays and fuses all appear fine.
Checked for implied spark with a timing light while cranking. All appears good.
Shorted the fuel pump testing thingy under the drivers seat, turned on ignition and crawled under the van.
This is where it gets confusing. I pulled the yellow connector next to the fuel tank, and I have 12 volts across the terminals.
I didn't hear any noises in the tank when I pulled or replaced the connector. Which would imply dead fuel pump unless I'm mistaken?
So two questions:
1) Is the yellow connector with two pins the correct connector for the fuel pump? There's a 3 pin white connector up around that area too.
2) would I always hear the fuel pump activate when applying 12V, or only if the pressure is low in the system? Reason I ask is that the hose next to the fuel filter appears to have pressure in it. Which is odd.
Thanks!

JonRoss
10-03-2012, 03:16 PM
So it turned out to be an issue with the EFI system not engaging, not the fuel pump. But I'm still curious why I didn't hear the fuel pump engaging?

wirewrkr
10-05-2012, 02:57 PM
So it turned out to be an issue with the EFI system not engaging, not the fuel pump. But I'm still curious why I didn't hear the fuel pump engaging?

If I remember correctly, the pump is turned on when the flapper moves in the Air Flow sensor (airbox). At least that's what it does on the old Bosch system that the Japanese licensed theirs from.

JonRoss
10-08-2012, 12:12 PM
The fuel pump testing jumper under the drivers seat bypasses the air meter contact, so the pump should start up with just ignition on. In theory...
Ah the mysteries of 26 year old vans!