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Discussion Starter #1
I guess this customer saw my 05 Elise parked at my shop some months ago and since we're are a foreign automotive repair shop, he had his 2006 Elise towed in yesterday.

To make a long story short, the customer claims he started the car and drove it out of the garage. Everything was fine and he continued onto the road when suddenly the car cut off and wouldn't restart. She cranks and has plenty cranking juice, but doesn't start. I noticed while I'm cranking the engine light will blink after 4 seconds of cranking. Not sure if that's normal since it won't start.
Here is what I've done so far. I researched this forum and tried some of the advice given. The inertia switch did click resetting it, but that didn't change nothing. I unplugged the switch checking for corrosion at the connection -- there is none. I checked all the fuses I could find, engine bay and under the front cover. None are blown.
Last night I removed the passenger seat, the seat belts and then the cover behind the seats, I removed the plate where the fuel pump resides under. I don't hear the fuel pump!! I then proceeded with a bid of starting fluid in the intake and the engine started fine. Obviously the fuel pump is keeping the Elise from running.
The fuel housing has 2 harnesses and since both have more than 2 wires, I wasn't sure which one is the level and which the pump.

Some people here suggest to remove the tank if the pump is bad and needs to be changed. Does that mean changing the pump through the opening behind the seat is very iffy or not possible at all?
However, I need to find out first why she won't start. Is there a fuel pump relay? If yes, where is it located? Anything else I need to check first?

I read somewhere online that the immobilizer can be bypassed not having to operate the fuel pump anymore, can somebody email me the procedure in case I need to do that? ([email protected]) Having a 2005 Elise myself got me scared and I'd like to be prepared.

Anyway I'm going on vacation next week and none of my other mechanics is willing to work on this customer's Elise. I need to get it diagnosed asap. If you one of you gurus don't mind calling my cell and talking me through the diagnostic procedure let me know and I'll email my cell number.

--Martin
--Autobahn Auto

2011 Golf TDI-R (custom)
2009 GTI
2005 Yellow Lotus Elise
1995 993 Cab
1995 E320 Cab, 5-speed manual (custom)
 

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For the purpose of test, measure if you have 12vdc available to the fuel pump (multimeter time). If there is 12 volts to the pump (not to be confused with power to the sender which measures fuel level), then you likely have a bad pump. If there is no voltage, then disconnect the wiring from the pump, and directly wire in 12vdc. If the pump runs and the car starts, then you are going to track down a potential immobilizer issue. If the pump still doesn't run with 12 volts applied, then you are looking at a bad pump, easy peasy.
 

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Discussion Starter #3
Gotcha, but the issue I'm having is the wiring to the fuel pump housing. There are two harnesses, one plugs into that little black box with 3 wires. The other plug has like 5 wires and most of them are black. Which are the wires to the actual pump inside?
 

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For the purpose of test, measure if you have 12vdc available to the fuel pump (multimeter time). If there is 12 volts to the pump (not to be confused with power to the sender which measures fuel level), then you likely have a bad pump. If there is no voltage, then disconnect the wiring from the pump, and directly wire in 12vdc. If the pump runs and the car starts, then you are going to track down a potential immobilizer issue. If the pump still doesn't run with 12 volts applied, then you are looking at a bad pump, easy peasy.
This is exactly what I would do to diagnose.

I suspect it is not the fuel pump either but rather a wiring/immobilizer/inertia switch problem.
 

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Discussion Starter #6
All the wires to the pump housing look the same, how I know which go below the housing and onto the pump? When I know which wires I can test them for voltage.
 

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For that information, you likely will have to find the free schematics which are available for the pump. I looked at my schematics (to an S1 Elise) and it shows connection "B" is plus 12v for the pump and "D" is the ground for the pump. But, there may be wiring difference for the pump between the S1 (pre import) and the S2 (American) elise. The letters may be hard to read on the connectors (if there are even letters to be found).
 

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If you have to buy a new fuel pump make sure NOT to buy one from Lotus. They were going to charge me $1000, but Monkey Wrench had one for under $100. It's louder since it doesn't fit in the housing as well as the stock one, but works just as good.
 

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Discussion Starter #9
Went to work and had another look. The wiring on the immobilizer is all the same color!! What in the world????

I wish there was more info online cause I'm pretty much forced to pull the fuel pump just so I know which wires in the harness go to it. :mad:
 

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Ive experienced a similar problem before. Is the fuel pump priming everytime you turn on the ignition? If not, than the multi function relay is a good suspect. You wont get 12v at the fuel pump during startup if your multi function relay isint energizing.



In this image its # 2.

Locate this unit, and try giving the wires going to it a giggle or disconnect and reconnect the wires going to it, ensuring a good connection. If the connection is good, and it still dosent energize, your multi function relay might have crapped out. Ive heard of this happening before.

But if you can verify 12v at the fuel pump, than your fuel pump may be the failed component like addertooth said.

But i'd really check multifunction relay if i were you. Its cheaper and easier to change than a fuel pump. Juz my 2 cents.
 
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