fuel pump is on when rpm is 0 ?

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4acrazy
MegaSquirt Newbie
Posts: 3
Joined: Tue Sep 08, 2009 5:59 am

fuel pump is on when rpm is 0 ?

Post by 4acrazy »

Hi
Just done my MS2 v3 wiring , and found that fuel pump keep runing when I switch on the ecu without start the engine .

I add a relay for the pump and trigger from pin 37 .

do I need to setting something 1st ? ( m using TunerStudio )
trakkies
Super Squirter
Posts: 1162
Joined: Tue Dec 30, 2008 3:06 am
Location: SW London, UK

Re: fuel pump is on when rpm is 0 ?

Post by trakkies »

4acrazy wrote:Hi
Just done my MS2 v3 wiring , and found that fuel pump keep runing when I switch on the ecu without start the engine .

I add a relay for the pump and trigger from pin 37 .

do I need to setting something 1st ? ( m using TunerStudio )
It should run for a few seconds then stop. This is to pressurize the fuel rail after a long stop. It should then start running again when MS gets a signal from the ignition that the engine is turning.
Dave P, London UK.
Rover V-8
MSII V3
EDIS
Tech Edge Wideband
4acrazy
MegaSquirt Newbie
Posts: 3
Joined: Tue Sep 08, 2009 5:59 am

Re: fuel pump is on when rpm is 0 ?

Post by 4acrazy »

tested with stim again today ,

when rpm 0 the LED go off after 2sec

once I turn the rpm rotary swithc the LED go on

sound ok right .

but once I plug into my car engine hardness and turn on the ecu power the pump on all the way non stop ( never start engine , rpm 0 )

so recheck the wiring and relay all ok .

so tested withstim again found when ( rpm 0 LED off ) it was a 5v output at pin 37 , that why the pump relay was trigger from !

when turn the rpm rotary switch the LED on a 12v at pin 37 , ok this find right .

so my problem is why the pin 37 output a 5v when rpm 0 ?

or something wrong with my MS2V3 ?
patrickbrown
Helpful Squirter
Posts: 48
Joined: Sun Feb 15, 2009 4:42 pm

Re: fuel pump is on when rpm is 0 ?

Post by patrickbrown »

I'm looking at the wiring diagram and it looks like pin 37 is actually a switched ground link. I don't believe you should see 5V there. The FP relay pin 36 (assuming Bosch/Tyco) is switched 12VDC and relay pin 85 should go to MS pin 37.

Someone correct me if I'm wrong.
Patrick Brown

MS2-V3 (2.891) - EDIS8
62 Ford Falcon - 331 Stroker
4acrazy
MegaSquirt Newbie
Posts: 3
Joined: Tue Sep 08, 2009 5:59 am

Re: fuel pump is on when rpm is 0 ?

Post by 4acrazy »

sure it is -5v when ignition power on without fire up engine .

-12v wen engine fire up .

found that on pin 30 (IAC output for on/off valve only ) samething as pin 37 , when off -5v , on -12v
Spittybug
MegaSquirt Newbie
Posts: 29
Joined: Sun Jun 27, 2010 9:39 am

Re: fuel pump is on when rpm is 0 ?

Post by Spittybug »

Yup, previous post confirmed. All works fine with a dedicated relay just for FP. Just have to have the FP relay grounded through pin #37 while the FI and LC1 circuits go straight to ground, just like schematic.
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