pcm shift light for 2nd fuel pump
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Anyone ever tried to use the shift light output in the pcm to trigger a 2nd fuel pump relay? seems like this would be easier and more tuneable than the typical hobbs switch
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You can probably do it, but it would be RPM based rather than MAP based: http://www.hptuners.com/forum/showthread.php?t=28762
I have seen Honeywell Hobbs switches that toggle hundreds of time daily in process applications and for the [currently] 10 years that they have been in service, they are all still working. I usually trigger second pumps between 1-3psi personally.
I have seen Honeywell Hobbs switches that toggle hundreds of time daily in process applications and for the [currently] 10 years that they have been in service, they are all still working. I usually trigger second pumps between 1-3psi personally.
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thanks for the reply frost, I def dont doubt the reliability of the hobbs switch, I was just trying to think up a way to tune a "test"' for the 2nd pump. like maybe a set a spot for that shift light at say 60% tps between 11-1300 rpm. That way you could roll on the throttle in sixth and make sure the pump powered up correctly without building boost( i have an led on the dash in parallel with the pump, although this would only test the electrical side) the failure mode i worry about is the pump or the relay.
its already wired with a 2 psi switch and i prolly wont change it, just posted out of curiousity
its already wired with a 2 psi switch and i prolly wont change it, just posted out of curiousity