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David Gieswein
David Gieswein,
Category: Car
Satisfied Customers: 103
Experience:  Automotive technician at Doug Gray Dodge/Chrysler/Jeep
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I have two fuel pumps working on 1978porsche 928 CFI

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I have two fuel pumps working on 1978porsche 928 CFI injection one # is(###) ###-####the other is SJ910-3805

Hello my name is ***** ***** maybe I can help. I own a 1978 Porsche 928 in which I have done much work to. Perhaps I may be able to help you. What is your question.

Customer: replied 1 year ago.

Hello David

I have two fuel pumps new I put one on and the car will not start havent checked the Pressure yet.but there is no fuel at the warm up regular. not sure this pump is for hi pressure that this system needs to operate bought these off Ebay they are new one is #0580254984 the other is #SJ910-3805

I too only am using one fuel pump and I also bought it off ebay. I cant tell you right now what the p/n is until I get off work. I the meantime, I believe the fuel comes up to the engine to the fuel distributor first. There is a small screen in the inlet of the fuel distributor you need to check. Also while you are checking this, check that fuel comes out of this line by cycling the key or trying to crank the engine. I will give you what I know off hand first, when I get off work I can really help you

Are you still there? I replied but did not get a response.

Do to a no response condition from the customer I am opting out.

Customer: replied 1 year ago.

I went ahead and put a gauge on the output line and there is 85 pounds there so I will look some where else. Thanks For your help

Ed Doherty

Do you still want help on this issue?

Customer: replied 1 year ago.

I have a follow up question that you are the only one that can help you will have to look on your car the 1978 928. Coming out of the center of the fuel distributor that line goes to a vacuum regulator I think its a regulator the output of that regulator goes to the input of the warm up regulator. the vacuum regulator has a place for a vacuum line to be attached mine does not have a vacuum hose on it should there be a hose on that regulator. If we could talk i could explain it better.

Ed Doherty

(###) ###-####/p>


I can talk later tonight if you like. I am at work right now. I get off at 6pm central time. I will contact you then if you like.

If you need assistance I am willing to help you, but you must rate me first. I don't work for free. My time is very valuable. If you rate me I will call you and give you the info you need. Sorry to be so blunt but I have been getting a slew of customers lately that get their answer and then don't pay. I don't get paid until you rate me.


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