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> Fuel Pump Power Question
lsintampa
post Aug 1 2013, 12:05 PM
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75 914/4 2.0 FI

I pulled out my fuel pump and hooked it up to 12V supply and it just doesn't spin like I'd expect.

SO, I assume it's dead.

In any event, I hook up a voltmeter to where the fuel pump connects and when I turn the ignition to the on position, all I get is about .50 volts.

Shouldn't I be getting a reading near 12 volts?

The wire I'm thinking is the fuel pump power is black / red - it's the only wire near where the fuel pump mounts, so I assume that at least is correct.

Thanks,

Len
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SirAndy
post Aug 1 2013, 12:19 PM
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QUOTE(lsintampa @ Aug 1 2013, 11:05 AM) *
Shouldn't I be getting a reading near 12 volts?

The fuel pump is powered by the FI brain.

Just turning on the ignition without cranking the starter will only run the pump for a very short time to build up pressure.
The pump will not see 12V until you start cranking or the engine is running.

Again, power to the pump is controlled by the FI brain ...
(IMG:style_emoticons/default/popcorn[1].gif)
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lsintampa
post Aug 1 2013, 12:33 PM
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QUOTE(SirAndy @ Aug 1 2013, 02:19 PM) *

QUOTE(lsintampa @ Aug 1 2013, 11:05 AM) *
Shouldn't I be getting a reading near 12 volts?

The fuel pump is powered by the FI brain.

Just turning on the ignition without cranking the starter will only run the pump for a very short time to build up pressure.
The pump will not see 12V until you start cranking or the engine is running.

Again, power to the pump is controlled by the FI brain ...
(IMG:style_emoticons/default/popcorn[1].gif)



Thanks Andy,

A few weeks ago, I fried my ignition harness - because the AAR was shorted - or at least that's the theory.

Since then I got a very good (used) FI harness (from Jeff) - mine was really bad, and I've rebuilt the ignition harness.

Anyway, I didn't have the FI harness grounded. It has 4 spade ground contacts where my old harness had fish eye connectors that were easily attached to one of the tranny bolts.

I grounded the FI harness (temp) and I did get a 12V jump on initial key on.

I guess I'm good once I figure out how to ground those spade connectors.
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76-914
post Aug 1 2013, 12:41 PM
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That piece is just a 4 prong spade fitting that is attached to the engine block on r side rear top case bolt. Keep on keeping on. (IMG:style_emoticons/default/beerchug.gif)
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TheCabinetmaker
post Aug 1 2013, 01:14 PM
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NAPA has a replacement Bosch pump for under a hundred.
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JeffBowlsby
post Aug 1 2013, 05:07 PM
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The three FI harness grounds have 3 lugs...looks like this...do you have one laying around?


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lsintampa
post Aug 1 2013, 06:54 PM
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QUOTE(Jeff Bowlsby @ Aug 1 2013, 07:07 PM) *

The three FI harness grounds have 3 lugs...looks like this...do you have one laying around?



Nope, my old harness had eye connectors, not spades.
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lsintampa
post Aug 2 2013, 07:03 AM
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QUOTE(The Cabinetmaker @ Aug 1 2013, 03:14 PM) *

NAPA has a replacement Bosch pump for under a hundred.



You have a link to that fuel pump? Only ones I can find are much more than that.
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stugray
post Aug 2 2013, 08:39 AM
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When I bought my last 914, the PO gave me a bunch of extra FI parts including Fuel pumps.
Included in the stash are two non-stock pumps that appear to be Mitsubishi FI pumps.

If anyone knows that they can be used on our FI, I would ship one to you:

(IMG:http://www.914world.com/bbs2/uploads_offsite/i366.photobucket.com-10819-1375454388.1.jpg)

I could test it first and see what kind of pressure they generate.

Stu
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TheCabinetmaker
post Aug 2 2013, 10:38 AM
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napa #N69133. In stock in tulsa 92.95
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lsintampa
post Aug 2 2013, 10:48 AM
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QUOTE(The Cabinetmaker @ Aug 2 2013, 12:38 PM) *

napa #N69133. In stock in tulsa 92.95



Got it - thanks!
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jim_hoyland
post Aug 3 2013, 07:10 AM
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Get that VIN ?
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Is that FI part # just for 2 liter systems ? Could be used as a replacement on a 1.8 L-Jet where the pump is located in the front.
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TheCabinetmaker
post Aug 3 2013, 07:30 AM
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Yes. Its the same as the 75/76 1.8L
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lsintampa
post Aug 4 2013, 02:47 PM
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QUOTE(Jeff Bowlsby @ Aug 1 2013, 07:07 PM) *

The three FI harness grounds have 3 lugs...looks like this...do you have one laying around?



I have not one laying around, I have not one before, I still have not one of those funny things.

I have searched high and low to find one.

If this is hard to find (like locally or soon), I'll put fish eyes on those wires - like what my last harness had.

Is that the "standard" method - is there a part number for that piece - and what is it called????
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JeffBowlsby
post Aug 4 2013, 03:29 PM
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Hey Len, I have an extra 3 prong ground lug I can send you. check your PM's
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