 fuel pump |
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| mrobin |
 Dec 19 2005, 04:41 AM
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#1
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Member  Group: Members Posts: 69 Joined: 1-August 04 From: boynton beach fl Member No.: 2,425  |
hi. (72 1.7 FI). my fuel pump won't run. I've checked all the fuses, relays etc.
when I used an alternative power sourse (battery charger) to the fuel pump it works, so I know it's an electrical problem. Could it be in the actual ignition switch ??? Just looking for ideas, let me tell you I am really bad at electronics, so please keep answers so an normal ignorant person (myself) can understand. tks for your help. mike |
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| Rusty |
Dec 19 2005, 05:38 AM
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#2
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Wanted: Engine case GA003709 Group: Admin Posts: 7,941 Joined: 24-December 02 From: North Alabama Member No.: 6 Region Association: Galt's Gulch 
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Have you jumpered the relay on the relay board to see if you can make the pump work with the key in the "run" position?
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| mrobin |
Dec 19 2005, 05:45 AM
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#3
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Member Group: Members Posts: 69 Joined: 1-August 04 From: boynton beach fl Member No.: 2,425 |
no,, haven't. so I'll give it a try.
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| SirAndy |
Dec 19 2005, 11:05 AM
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#4
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Resident German Group: Admin Posts: 41,614 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
back to the basics first ... FI brain hooked up? you do know that it will only run for 2 seconds and then stop when you just turn on the key, right? (with the brain hooked up) it will only run continously if the motor is cranked or running. how did you check the relays? if your headlights are working, use one of the headlight relays and replace the pump relay with it. make sure you get a tight fit, if it feels lose, carefully pry the prongs apart a bit. is your wiring original or does the car have some "custom" wiring? how is the overall condition of your relay board? (IMG:http://www.914world.com/bbs2/html/emoticons/cool.gif) Andy |
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| Dave_Darling |
Dec 19 2005, 12:38 PM
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#5
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914 Idiot Group: Members Posts: 14,981 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California
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Text article on the D-jet fuel pump control system--
http://www.914fan.net/fuelpump.html Flowchart for troubleshooting the D-jet fuel pump control system-- http://members.rennlist.com/pbanders/FPChecklist.htm --DD |
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| mrobin |
Dec 19 2005, 01:02 PM
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#6
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Member Group: Members Posts: 69 Joined: 1-August 04 From: boynton beach fl Member No.: 2,425 |
thanks for input.
the FI brain is hooked up, I know that it only runs 2 seconds prior to starting. the car has run great forever, just yesterday I turned the switch and didn't hear the fuel pump run. I checked relays, by swicthing the other realays with items that run ok. The overall condition of the relay board is excelent, matter of fact the PO was realy meticulus about all the wiring. Last night I hot wired the fuel pump (just ran wires to ground and to the fuse box). it ran ok, but I know that's not the right way to do it. |
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| SirAndy |
Dec 19 2005, 01:22 PM
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#7
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Resident German Group: Admin Posts: 41,614 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
another stupid thing before you dive into the world of (semi)electronics ... did you rotate the fuses? sometimes, especially in moist weather, the contacts can corrode just a bit and even thought the fuse is not burned up, it won't make contact. rotating them in their socket will fix that. also, even thought it is very unlikely, your brain could have died! (IMG:http://www.914world.com/bbs2/html/emoticons/cool.gif) Andy |
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| r_towle |
Dec 19 2005, 01:40 PM
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#8
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Custom Member Group: Members Posts: 24,571 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States
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I would first do the follwing...after you rotate the fuses...
check with an ohm meter, or with a light bulb and some sets leads... check the wiring from the relay board to the fuel pump...if it is in the stock location, there is a gromet in the engine shelf that might be gone and the wires might be chaffed or cut... So check that set of wires first...the colors are the same on both ends... The next thing I would do, and have had to do...it get some of the spray type electrical cleaner...it is alchohol based... Get a clean tooth brush. Take off each connection at the relay board and at the FI brain and clean clean clean... Rich |
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| r_towle |
Dec 19 2005, 01:42 PM
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#9
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Custom Member Group: Members Posts: 24,571 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States
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I forgot one...
Check the read lead from the starter to the relay board..make sure it is clean at the starter...and at the relay board. Rich |
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| mrobin |
Dec 19 2005, 03:02 PM
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#10
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Member Group: Members Posts: 69 Joined: 1-August 04 From: boynton beach fl Member No.: 2,425 |
thanks for the help.
I already did the fuse thing (put all new fuses in actually). but i'll try the starter to the relay conections. every other conection I can find, I steel wooled and cleaned with achohol (then drank some.) thanks again |
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| mrobin |
Dec 19 2005, 03:15 PM
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#11
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Member Group: Members Posts: 69 Joined: 1-August 04 From: boynton beach fl Member No.: 2,425 |
Another question. What hapens if I run the car with the fuel pump hot wired to the fuse box ? Is this bad ? The car runs that way, but I don't want to cause any damage.
tks |
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| SirAndy |
Dec 19 2005, 03:41 PM
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#12
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Resident German Group: Admin Posts: 41,614 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
yes, it's bad. the FI brain controls the pump. if you hotwire the pump, the brain can't shut it off. if you crash your car and the motor stalls, the pump will still run and you'll burn into a rice-crispy. other than that, you'll probably be fine ... (IMG:http://www.914world.com/bbs2/html/emoticons/cool_shades.gif) Andy |
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| mrobin |
Dec 20 2005, 05:20 AM
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#13
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Member Group: Members Posts: 69 Joined: 1-August 04 From: boynton beach fl Member No.: 2,425 |
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| mrobin |
Jan 6 2006, 04:57 AM
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#14
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Member Group: Members Posts: 69 Joined: 1-August 04 From: boynton beach fl Member No.: 2,425 |
update...
thanks to all for your help. it was the relay. even though I switched a couple of relays arround, it didn't help...then i put in a new relay and ...hurray it work's.... |
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| Poze |
Jan 6 2006, 11:58 AM
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#15
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Newbie Group: Members Posts: 2 Joined: 12-December 05 From: Dorset, UK Member No.: 5,267 |
I have exactly the same problem on my 914, primes for a second then dosent start. Or starts if i hot wire the pump on.
I've tired most of the above bar replacing the relay with a new one( swapped em round etc). I'll try and make the relay contact tighter, as at mo it just slips in easily. What a pain! hoprfully this will sort my 914 1.7L !! cheers and i ve printed off all the info, Paul |
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