Author Topic: DIY Fuel Pump Replacement  (Read 36620 times)

browntown

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DIY Fuel Pump Replacement
« Reply #15 on: February 22, 2010, 02:40:59 PM »
Anyone have one of these fail? Seems to be a couple posts between r3v and e30tech that say the tre's are crap.  I can live with a little more noise of walbro if it's a better quality unit.  

Also, does anyone have pictures of retrofitting a bosch 040 (intank version of 044) onto the intank assembly?

quinn11m20

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DIY Fuel Pump Replacement
« Reply #16 on: February 22, 2010, 03:42:50 PM »
I will be doing that not too far into the future. My baby's pump, relay and CPS all apparently went bad. IDK?

Rich Dixon 91is

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DIY Fuel Pump Replacement
« Reply #17 on: October 03, 2010, 04:09:17 PM »
I'm suspecting my fuel pump is why I'm not running. I died while running and I've got spark but no gas. I've got the cover off the fuel pump. Should I hear anything out of it if I click the key back and forth?

DesktopDave

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DIY Fuel Pump Replacement
« Reply #18 on: October 03, 2010, 06:16:53 PM »
Check the crank position sensor & FP relay before you condemn the pump.  The car will not energize the pump relay if the CPS is giving no signal.  It's a safety feature, admittedly a dumb one.

You should see about 680 ohms IIRC on the crank sensor.  You can test the pump by pulling the relay & jumping terminals 30 & 87 with a short bit of wire.  It should start running with the ign. switch in pos. I or II.
« Last Edit: October 03, 2010, 06:19:32 PM by DesktopDave »
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Rich Dixon 91is

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DIY Fuel Pump Replacement
« Reply #19 on: October 03, 2010, 09:25:31 PM »
Quote from: DesktopDave;97104
Check the crank position sensor & FP relay before you condemn the pump.  The car will not energize the pump relay if the CPS is giving no signal.  It's a safety feature, admittedly a dumb one.

You should see about 680 ohms IIRC on the crank sensor.  You can test the pump by pulling the relay & jumping terminals 30 & 87 with a short bit of wire.  It should start running with the ign. switch in pos. I or II.

I've got 12v at the pump plug when I turn the ignition on to start. Newb with a multimeter, but it looks like 800 ohms on the crank sensor and 1800 on the cam sensor. Those readings with 12v at the pump when I turn the ignition tells me the sensors and the relay are working, and the pump is bad. I guess I need to put power straight to the pump and see if it does anything.

Hope this wasn't a thread hijack...never hurts to bump a DIY!
« Last Edit: October 12, 2010, 09:27:34 AM by Rich Dixon 91is »

Simon S

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« Reply #20 on: April 19, 2011, 05:32:24 PM »
First off: big thank you for all the information and pictures – BIG help !!

After swapping in a TRE pump, my #11 (7.5 amp) pump fuse consistently fails.

At first – fuse would fail after ~60 seconds.
After cleaning/replacing connections at fuel pump – and cleaning ground point behind rear seat, fuse would fail after 20-30 minutes (some improvement)

I contacted Nick North of TRE – and was informed that the pump typically draws between 10-12 amps.

I’m going to try a 10 amp fuse – if it works, great – otherwise I really don’t want to jump up more than 5 amps on factory wiring. Can’t find anyone that makes a 12A mini spade fuse – which would be ideal. Installing a 15 will be my last, LAST resort..


Couldn’t get a hose clamp on assembly – it wouldn’t fit in tank opening – reluctantly used a zip tie.


Also – I contacted Nick regarding supplied fuel line being submersible – he assured me it was (fwiw).
------------------------------------------Zen and the Art of e30 Maintenance

Simon S

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« Reply #21 on: April 20, 2011, 10:30:14 PM »
Follow up: put 1-1/2 hours run time on today with a 10 amp fuse. Ran fine. I'm happy.
------------------------------------------Zen and the Art of e30 Maintenance

sbarton

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DIY Fuel Pump Replacement
« Reply #22 on: April 25, 2011, 09:09:16 AM »
great write-up.

-Scott

Drewdown

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« Reply #23 on: May 31, 2011, 03:42:48 PM »
Great write up.  Thanks.

Anyone have anything definitive on TRE vs Walbro?

rac3r

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« Reply #24 on: June 04, 2011, 04:24:44 PM »
I put in a new fuel pump assembly, but I replaced the entire assembly instead of just the pump. Is only changing the pump a lot cheaper?

Don't forget to disconnect the battery too. I also like to move the car out of the garage when dealing with the fuel system so that the house doesn't burn down if the car catches on fire.

blalor

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DIY Fuel Pump Replacement
« Reply #25 on: July 05, 2011, 05:30:37 AM »
Quote from: rac3r;104386
I put in a new fuel pump assembly, but I replaced the entire assembly instead of just the pump. Is only changing the pump a lot cheaper?


Yes.  The pump seems to be between $60 and $100.  The OEM replacement assembly is at least $240 (from what I've been able to find).