How to test double pumper?

[GG87GN]

I have recently been having some surging issues at WOT. I figure it's fuel or spark. Coil checked out gonna swap out Ignition Control module with a friends good one. But I have an older style double pumper that came with the car might be Reds with hobb switch set at 15#. When I put a jumper wire across hobbs switch at idle the fuel pressure will not move, should FP jump up? Is second pump not comming on?

No knock O2 780mv just when engines hot WOT surging/hestitation, fuel pressure at 20+ boost is over 60#.

 

[SHADOWII]

Assuming the hobb's sw. goes to the 2nd pump directly, your diagnosis would be correct. The 2nd pump is not working.Have you verified that voltage is available at the hobb's sw. and not used to/or be powered by a relay?(Not knowing your wiring configuation.)

 

[Chuck Leeper]

Jump the Hobbs, disconnect the primary pump. Engine die? Fuel psi when you do that, is?

 

[fastblackracing]

just jump the hobbs switch with the car OFF. most are wired right from the alternator to the switch to the pump. the pump should run with the car off . Let me know what happens ok?

 

[GG87GN]

Just Jumped the Hobbs switch with car off key on I could here the primary pump charge the fuel sytem to 40psi then when I jumped the Hobbs switch nothing. The Hobbs is connected to a relay too. I will try to check the voltage, I may not have power to the switch. I have read some post where the relay is not necessary? I wish I had the new Recetronix set up where I could just swap the pump wiring to check the second pump. Thanks for the assistance.