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Discussion Starter · #1 ·

I have been having intermittent issues . Basically the car would suddenly just die for no reason and read 0 fuel even if the tank was full, and the fuel pump that is supposed to run for 3 sec before starting would run constantly. Now it wont start at all.


http://www.boefabrication.com/downloads/TVS_Install_plus_EFI_pdf.pdf (Page 26 is where the EFI wiring starts and that is the EFI I am using)
Hi David,

We've carried out some checks on the car as follows:

No fuel being delivered to cylinders - injectors
No spark
Inspected bores
No connection at OBD port

As the engine will tun and fuel pump runs, it's not immobiliser. We think it's the ECU. ***Replaced ECU did not fix the issue***

A new Lotus ECU (US spec) is £409 + vat. I can get one in for next week. Please can you let me know if you are ok for me to order up.

Kind regards
Marianne
Hi Dave,
Our technician Sam has gone through the BOE docs and checked the wiring and has confirmed that the wiring is as it should be. We fitted the new ECU yesterday when it arrived, but it hasn't resolved the issue.

He has identified that there is a change in voltage to the injectors which we can't explain. It drops from 12v to 2.5 I think (sorry the guys are at Brands Hatch today) and we originally thought that it was the fault of the ECU, but we now know that's not the case. When we supply 12v to the injectors the fuel pump cuts, which doesn't make any sense.

There is a Multi function relay unit on the car which we have swapped for a new one, which hasn't solved the problem either.

That's a far as we got on Friday. We will start again on Monday.

Do you know anything about the piggy back ECU? We're wondering if this controls the fuelling, so the issue might be there?

Kind regards
Marianne
Anyone have any ideas?
 

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"Play it again Sam" being a reference both to the movie scene, as well as that your technician (Sam) might have more work to do. But I see now that it was Ingrid Bergman and not Lauren Bacall that was in that movie.

The "What is common other than the ground", is a reference that the ground is also called "the common". If the ground is not good, then the current through the injectors could be raising the ground and stopping that current flow through the pump.

A ground issue scenario results in "Play it again Sam" for the technician to sort out the wiring.

Or the injectors getting hooked up and the fuel pump stopping might be removing the incoming current from the pump and diverting that to the injectors.

Either way it sounds like wiring is likely.
 

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I would suggest having them measure the AC and DC voltage at the fuel pump's + and the fuel pump's - relative to a direct connection from the VOM to the battery.

Repeat the measurements for the injectors for the injector's + and -.

Then post the results.
 

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Interesting, it does seem we have the same issue, though mine has not done this before, and cannot get running again. You are also running separate EFI. My ECU is still stock, with a koldfire tune (REV400). I have yet to start pulling it apart to diagnose......

You said your's does this intermittently, how frequently has this happened? Did it run normally after it happened the first time? Also, what year is your's? Mine is an 06.

I have a feeling something is giving the ECU a bad voltage / reading, and causing it to "shut down" to protect itself.
 

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Discussion Starter · #8 ·
Interesting, it does seem we have the same issue, though mine has not done this before, and cannot get running again. You are also running separate EFI. My ECU is still stock, with a koldfire tune (REV400). I have yet to start pulling it apart to diagnose......

You said your's does this intermittently, how frequently has this happened? Did it run normally after it happened the first time? Also, what year is your's? Mine is an 06.

I have a feeling something is giving the ECU a bad voltage / reading, and causing it to "shut down" to protect itself.
It would happen on a maybe once a week but it got more frequent until the over all failure which went from weekly to daily every start and then it stopped starting. Mine is an 06 as well with a force fed 275 turbo.

Edit:Is your fuel gauge doing the same thing?
 

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Discussion Starter · #9 ·
Car is now running! We found a crack in the solder joint into one of the DRS connections. Needle in the haystack!



We need to re-assemble the car and then will drop you a line.


Greg.


Greg Lock
Hangar 111 Limited
:clap::clap::clap::clap::clap::clap::clap::clap:
 

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Discussion Starter · #11 ·
I have yet to collect my car but I will bring my camera. Are you running the DRS EFI setup?


Edit:Im dumb haha I forgot you posted your setup. As far as I know it was one of the connections inside of the http://www.efitechnology.com/12.html EFI
 

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No, I'm still using just the stock ECU. I'm asking what the faulty wire controlled. If it was the main power wire or something.
 

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Discussion Starter · #13 ·
No, I'm still using just the stock ECU. I'm asking what the faulty wire controlled. If it was the main power wire or something.
I will scan the stuff they have highlighted on monday and post it here I also emailed them to inquire which exact wire it was.


What they had highlighted though was

L/R:pin:Name:Type:Number:Cable:Thickness


L:E3:Fuel Tank Sender:111:KU:0.5

L:H1:pPS1_GND:Throttle Pedal Sensor 1 Ground:78:B:0.5

L:K2:pPS1_REF:Throttle Pedal Sensor 1 5v:281:0.5

L:L4:Fuel Tank Sender Ground:104:B:0.5

L:M1:Main Power In:Spliced into Main relay and Injector 1:217:G:0.5
L:M2:Main Power In:Spliced into Main relay and Injector 1:218:G:0.5
L:M3:Main Relay:34:WK:0.5


L:M4:Fuel Tank Sender:102:S:0.5
 
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