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Totally Confused - Fuel Pump Works without Emerald wired in??? - Update Resolved by Peter Carmichael

MikeE

By MikeE
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MikeE

MikeE

Posted
Posted

I've been asking for advice on the wiring up of my new Emerald on this thread here

 

 

So yesterday I start looking at the wiring and before I do anything with the 7 wires described in the other post I think I'll just try turning the engine over. So I turn the key and the fuel pump starts whirring away despite the fact I hadn't connected the two fuel pump and relay wires described in the other thread.

 

So first question is how? And also why do I need to connect the pump via the ECU and the Emerald fuel pump relay anyway?

 

Clearly the pump is being fed with an electircal supply but is it possible there's insufficient current to provide the required fuel pressure as I don't believe there's a relay in the circuit?

 

So I then connect the Emerald up to the 12v switched supply and the red LED comes on, I use the SAME 12v switched supply for the ignition and fuel pump relay inputs on the ECU. I then try starting it up and it turns over, the Emerald LED flashes Red and Green (so it sees the engine rotation?) but it won't start *confused*

 

So I then take a plug lead off and hold it against the exhaust primary and turn over again and I can see a very small spark.

 

Given I have a (small) spark and think I'm getting fuel to the fuel rail I don't understand why it won't start, I guess I either don't have sufficent supply to either the fuel pump and/or ignition.

 

TOTALLY confused and starting to panic now as my Emerald mapping sessions is Thursday next week *cry*

 

If anyone can give advice or better still anyone in the local area can pop over I'd REALLY appriate it *thumbup* *thumbup*

 

cheers

 

 

 

R400 Duratec Build and Modification Pictures

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Edited by - MikeE on 7 Sep 2007 12:06:12

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I.Mupferit

I.Mupferit

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Mike, when the fuel pump whirrs, does it just run for a few seconds to prime the system and then stop or does it keep on running?

 

Also, are the plugs getting damp with fuel?

 

Does the engine fire at all as though it is trying to start?

 

Brent

 

2.3 DURATEC SV Reassuringly Expensive

R 417.39 😬

 

Edited by - Brent Chiswick on 3 Sep 2007 11:58:41

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MikeE

MikeE

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Brent

 

The fuel pump whirrs continuously but then it always did

 

haven't checked the plugs but maybe I should clean then up and try again

 

don't think it's managed to catch at all in the 10 or so attempts I've made to start it, but then I did turn it over before I connected the ignistion relay so maybe by that point the plugs were fouled?

 

Could do with some diagnostic tools (like a fuel pressure guage) and some expert help!

 

 

 

 

R400 Duratec Build and Modification Pictures

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Andy Doughty

Andy Doughty

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Mike

Mines on an MBE but..........

The ECU will know if the engine is running so, after a few seconds it should turn off the pumps if the engine stops and the ingnition is on. This is to stop the pumps fuelling any engine fire after an accident. Check with Emerald but thats why they recommend using the ECU to control the pumps.

The relays that they recommend in the system just switch the heavy electrical load so it does not burn out the ECU.

Otherwise, you need some Emerald hooded coat wearers to help 😬

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I.Mupferit

I.Mupferit

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As Andy says, the pump should be run via the ecu so that it kills the pump when it recognises the engine isn't turning over.

 

What map have you got installed in the ecu? I know when I first fitted my Emerald ecu, the map I was given for a Duratec 2.3 wouldn't produce even the slightest hint of life from the engine as it cranked over despite there being nothing obviously amiss.

 

The second map I tried which was for an AMMO 2L engine allowed it to burst into life immediately!

 

Brent

 

2.3 DURATEC SV Reassuringly Expensive

R 417.39 😬

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I.Mupferit

I.Mupferit

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Well it might be worth trying another map, even a 4 injector one maybe, as I would have thought it would at least start and run even if not that well. I assume you are trailering it up to Emerald so provided it is wired up and runs then Dave Walker could sort out the proper map and running for you.

 

Brent

 

2.3 DURATEC SV Reassuringly Expensive

R 417.39 😬

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MikeE

MikeE

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if I fail to get it started tonight then might be worth a try

 

I'm wondering if turning it over last night without the ECU inignition feed connected fouled the plugs? Then when I connected the ignition and checked for a spark it was too late?

 

How do I dry the plugs, I assume just taking them out and cleaning them isn't necessarily enough as there might be fuel in the cylinders or is this likely to have evapourated or seeped past the piston rings by now?

 

 

R400 Duratec Build and Modification Pictures

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MikeE

MikeE

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Ok have checked all four plugs and I'm getting a spark

 

I've checked the fuel rail bleed screw and I'm getting fuel coming out when the pumps running

 

I've checked all the ecu loom connectors on the engine and they seem fine

 

The ECU light goes red and green when turning over the engine so it recognises the engines turning over

 

I temporarily disconnected the throttle pot as instructed by Ammo

 

and it still won't start!

 

So what else to check:

 

1 - maybe the battery's just not upto it?

2 - maybe the map just won't work on my spec?

 

anything else?

 

Brent - any chance of trying your map to see if that helps?

 

cheers

 

 

R400 Duratec Build and Modification Pictures

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MikeE

MikeE

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Ok a little more progress

 

I wonder if the ecu didn't like not having the ecu fuel power supply and fuel pump outputs connected so I took the plug out of the inertial switch and wired up the ecu fuel pump supplies.

 

The pump primed and then stopped (as you'd expect) i then started it and it fired up and ran for a second but died, turned off and on again and the same routine. So I think maybe the pumps not coming back on again but don't know why - maybe the ecus not recognising the engine running and so it doesn't switch the pump back on? Don't know but at least it fired!

 

Any ideas?

 

 

 

R400 Duratec Build and Modification Pictures

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rgrigsby

rgrigsby

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Not sure but I wouldn't worry too much, Emerald will be able to fix just about anything quicker than most people. My engine wouldn't run at all before I took it up there, turns out the loom I had was set-up for sequential injection but my emerald wouldn't support that as it was an early one. Karl modded it in about 30minutes and it was all fixed.

 

Rob G

www.SpeedySeven.com

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Peter Carmichael

Peter Carmichael

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I wonder if the ecu didn't like not having the ecu fuel power supply and fuel pump outputs connected so I took the plug out of the inertial switch and wired up the ecu fuel pump supplies.

 

This is a total distraction. Please don't tell me you're running high current feeds to the fuel pump direct through the ECU. The ECU pulls its outputs to ground and can handle a few hundred milliamps... enough for the coil packs and injectors and relays, but definitely not enough for a fuel pump.

 

It sounds like your wiring is somewhat different to a standard setup. Go carefully.

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MikeE

MikeE

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This is a total distraction. Please don't tell me you're running high current feeds to the fuel pump direct through the ECU. The ECU pulls its outputs to ground and can handle a few hundred milliamps... enough for the coil packs and injectors and relays, but definitely not enough for a fuel pump.

 

It sounds like your wiring is somewhat different to a standard setup. Go carefully.

 

Peter

 

According to my understanding of the Emerald wiring you provide a switch 12v supply to the ECU (fuel pump relay input) which I temporarily took from the feed to the inertia switch and the fuel pump output from the ECU loom is via the ECU fuel pump relay which I fed into the output lead on the inertia switch - why would this be wrong?

 

Like I said I'm confused

 

 

R400 Duratec Build and Modification Pictures

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Peter Carmichael

Peter Carmichael

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Standard Caterham wiring for the fuel pump...

 

... battery to fuse box (direct unless you have a master switch)

... ECU fuse

... purple wire returns to engine bay

... spade connector joins to brown wire main power feed on engine wiring loom

... main power feed sent to two input terminals on the MFU (big plug)

... ECU controls a low current pull to ground on the MFU fuel pump relay (pin 20)

... output from the MFU goes to inertia switch

... output from inertia switch goes via grey multiplug back to car wiring loom

... back to the fusebox

... through the fuel pump fuse (15A)

... down the loom connection in the tunnel to the fuel pump

... the earth return from the fuel pump comes back down the tunnel into the engine bay and earths to the chassis at the front brake circuit T union by the RHS upper wishbone

... the earth straps from chassis to engine and engine to battery complete the electric circuit

 

So....

 

... taking either of the two wires from the inertia switch and sending it anywhere near the ECU is not really a structured approach.

... with the Duratec installation some other arrangement of relays is probably in place

... you need the wiring to match the needs of the ECU... if you try and do it the other way round you will end up with a load of very expensive smoke.

 

 

... I'm just down the road, so can take a look if you like.

 

Edited by - Peter Carmichael on 4 Sep 2007 09:28:14

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MikeE

MikeE

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Peter,

 

Thanks for the advice, like I said I'm really not that hot on wiring.

 

I would really appreciate it if you could pop over and take a look, sure it would all be obvious to you! I'm actually in Fleet which is around 20mins from you I think.

 

Could you give me a call on 07940 499924?

 

thanks,

 

 

R400 Duratec Build and Modification Pictures

here

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MikeE

MikeE

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Now up and running, turns out that it was probably just the throttle pot that needed calibrating before it would start, not something I could do myself as I wasn't sent the emerald PC software CD for a K3 so couldn't set it.

 

Peter C spent hours on my car checking everything out, tweaking the map and sorting my coolant issues - unbelievably generous givne I don't know Peter so again thank you very much for your help and advice *thumbup*

 

R400 Duratec Build and Modification Pictures

here

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Stationary M25 Traveller

Stationary M25 Traveller

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quote:What happened Sunday?

 

 

 

I believe the under bonnet wiring on a rather well known car went up in smokeexclamation!!

 

Brent

 

If said WKC has a large zip - it was fixed and well again by Tuesday night at The Plough.

 

******************

And you run and you run to catch up with the sun, but it's sinking...

 

And racing around to come up behind you again. new link to photos

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