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Happily expanding the To Do list since 1997
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I think my cranking volts can get down into the 9's but 8.5 sounds kinda low. Have you checked the quality of the ground connections?

PS I do have a Walbro pump but it was provided with my supercharger kit long ago and I don't know if it's a 225 or 190.
 

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Happily expanding the To Do list since 1997
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Well, cranking pulls a couple of hundred amps through some connections so it's several times the current flowing in normal running. Even a slightly poor connection could drop a couple of volts in that situation and seem pretty normal the rest of the time. Really, the only two grounds that take that major hit are the battery terminal itself and where the other end of the battery ground lead bolts to the powerplant frame. (Under the car in front of the rear right wheel, you can peer straight in and see where the crimp eye on the end of the cable bolts to the PPF right next to the diff. For some reason the cable is inclined to fray and fracture there.)
 

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Mind you, if that was 10.5V measured at the battery it could still be a volt less when measured at the ECU, even if all the connections are good.

(I did a quick Google on expected voltage drop and found 125 - 150 amps seems to be typical for cranking a 4 cylinder engine. The ground cable is 16mm² and about 1.8m long, and at 125-150 amps it would drop over 0.5V from end to end. And that's only the ground cable; you'd drop voltage in the 12V cable too.)
 

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That rings a bell. On the original 1.6 the fuel pump relay isn't connected to the ECU. It's powered while cranking and then after that it's kept powered by a switch in the airflow meter (which stays on so long as there is some airflow). That's supposed to be a safety cutout so if the engine stops (in an accident or whatever) the fuel pump stops.

I don't know what complications being auto adds or what mods might be done to let you remove the AFM.
 

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I think it's a normal bolt. You just need to check the contact surfaces of the ring terminal and PPF and underside of the bolt head aren't corroded, and that there aren't many fractured strands where the cable is crimped into the ring terminal.
 

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Happily expanding the To Do list since 1997
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First thought is the 2 seconds priming will pressurise the fuel rail and that probably means there's enough fuel to start the car. That could be all the fuel you're getting. So it may be the pulsing effect you saw on that ground pin while running isn't enough to drive the FP relay. I think it needs to be established if that's normal. It sounds as if there's some kind of PWM drive signal on that pin there when perhaps it ought to be a solid ground. MSEXTRA forum is where I would go to ask.
 
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