 How much fuel should flow?, Out of fuel pump with EFI |
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| Rocky |
 Oct 4 2009, 07:27 PM
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#1
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From the cockpit  Group: Members Posts: 341 Joined: 24-March 04 From: Gig Harbor,WA Member No.: 1,845  |
My super reliable 75' 1.8 now will not start. It has stock injection. I do have spark! Injectors show no fuel outflow when cranked. I then went to the pump and when cranking over it shows a steady low flow of fuel. Shouldent I see a pretty high rate of pressurized fuel given these are putting out over 20 psi? This is the original fuel pump.
I know I havent posted in a while... Im a looser (IMG:style_emoticons/default/wacko.gif) Rocky |
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| r_towle |
Oct 5 2009, 04:00 PM
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#2
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Custom Member Group: Members Posts: 24,585 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States 
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The fuel pump does not come on in Ljet until after the car starts and air is moving enough to open the flapper in the AFM unit.
I think it is supposed to come on while cranking, but you need great compression and a fantastic battery to create enough draw to open the flapper....so old cars dont function like this anymore. I never liked that. Basically the system MUST stay up in pressure when parked, yet few really do over long periods of time....like winter storage. So, the fuel lines need to be checked and replaced, all of them. New metric hoses, new FI clamps (not hardware store clamps...get the good ones) when this happened to us, it was the fuel pump dying...so start shopping around for a fuel pump. You can remove the large intake hose at the AFM and with the key in the run position, stick your finger in the AFM and active the flapper door. You will hear the fuel pump run, and you will hear it change tone once the system is pressurized. Then put it back together and the car should start. Rich |
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Posts in this topic
Rocky How much fuel should flow? Oct 4 2009, 07:27 PM
type47 for a '75, I found in the workshop manual a fi... Oct 4 2009, 08:02 PM 914Sixer Check L-Jet testing info. Fuel pump power does no... Oct 4 2009, 08:23 PM Rocky If I assume fuel flow is adequate out of pump but ... Oct 4 2009, 08:33 PM
type47
If I assume fuel flow is adequate out of pump but... Oct 5 2009, 05:24 AM
Rocky
If I assume fuel flow is adequate out of pump bu... Oct 5 2009, 09:51 AM davesprinkle
If I assume fuel flow is adequate out of pump but... Oct 5 2009, 10:47 AM zonedoubt Check resistor pack, double relay.
Here's a g... Oct 4 2009, 09:49 PM Rocky Yep, its connected.
BTW, nice bike. 400 supers... Oct 5 2009, 11:12 AM davesprinkle Good eye. Yeah, it's a 400 four. My other pr... Oct 5 2009, 03:24 PM davesprinkle
The fuel pump does not come on in Ljet until afte... Oct 5 2009, 05:24 PM zonedoubt That's the function of the double relay.
http... Oct 5 2009, 05:33 PM Cap'n Krusty I'm gonna try to get the factory troubleshooti... Oct 5 2009, 06:04 PM Rocky All great advice! I will give it a once over ... Oct 5 2009, 08:01 PM Rocky Im on the road again!!! :driving:
Du... Oct 10 2009, 12:11 PM zonedoubt Good stuff! :headbanger:
L-jet isn't as... Oct 10 2009, 12:26 PM davesprinkle
Good stuff! :headbanger:
L-jet isn't a... Oct 10 2009, 01:22 PM |
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