12 replies to this topic

[maccers]

Have had engine out and lots of other bits since Feb, just got it all back together. I have an Emerald ECU running fuel injected s/c. It’s got a red light on it, and won’t turn the fuel pump on. Is it possible it’s lost its config/map? I’ve had the battery on trickle charge but disconnected from the loom since about feb. I assumed it was some form of ROM it got saved to or other non volatile memory. 

[Davidmt]

If you do not see the ECU status LED turn from red to green during cranking, please refer to our FAQ section on our website (EmeraldM3D.com - FAQs) for further advice.

 

 

Red light needs to change to green when cranking - you have an issue!

[Shooter63]

I had a car running an Emerald, check your ECU and body earth's, if they are all OK check your timing sensor is set at the correct distance and is working. I am presuming that the power feed is good as you have a red LED.

Shooter

[stoneface]

I run an emerald k6 and it's been left for 5 years without a battery connected and started today no problem, so it shouldn't have lost the map.

No problem is a bit of a lie as I couldn't get a spark at first but cleaned a few connection on the trigger sensor and it fired up.

[stoneface]

Also, if you have an inertia cutoff switch on the fuel pump, check its on and working.

[maccers]

Will check that the crank sensor. I always thought the fuel pump kicked in when the ignition was on but it’s been that long I can’t be certain. Replaced all the fuel lines while engine was out, tank was out, MPI type. Was checking for fuel leaks guess I could just power the pump direct from a 12volt source,

[maccers]

Also, if you have an inertia cutoff switch on the fuel pump, check its on and working.

There is no inertia, it’s wired from the ECU via a relay. It’s an MPI tank/pump. 

[stoneface]

Thats the problem I have. I built it so long ago that I forget how I wired everything up and then spend many hours trying to figure out the birds nest of wires.

I hate electronics and wiring. It's just coloured string that goes up in smoke when it goes wrong.

Mechanics is so much easier.

[Bobbins]

How high is the cranking voltage? If it’s too low the Emerald light will remain red during cranking, I can’t recall the exact voltage but I think it needs more than around 11 volts, it’s in the Emerald documentation … which I assume you have?

Have you also checked the immobiliser status?

[maccers]

Hmm, I’ve had the battery on trickle charge for a few months. I’ve not tried to crank it just yet, ordered some more oil as I only had a small drop left over. I was just seeing if there were any fuel leaks since I replaced all the lines and filter. I was convinced the fuel pump started when the ignition was on but come to think of it that would be a bit dangerous potentially! It’s definitely wired from the ECU so will be controlled by it using other variables no doubt.

Its not got an immobiliser, it’s a 1976 but retro fitted with new standard loom but additional loom to support the fuel injection bits and bobs.

[stoneface]

My fuel pump comes on with the ignition switch before the engine is started.

I suppose it depends how you have it wired.

[sonscar]

Most systems run the fuel pump briefly at key on to prime the system.There should be a relay that the ECU provides the earth to.Just my experience,Steve..

[stoneface]

Thats exactly what mine does. It primes on first key turn.