Elise Will not Start - Please help

[Go Figure]

Hi, I wonder if anyone has any ideas to help solve a non starting problem. I have searched the forums and whilst there are lots of posts about non starting, none seem to match my cars' symptoms. I have recently bought a T reg Elise (non VVC). The previous owner had problems where the car would not start and the garage changed the fuel pump about 12 mths ago(and messed with the sender) - I did ring them and they were very defensive about their work! Since I have owned the car it has not started on a couple of other occasions but this either fixed its self or I did something messing about with the wiring which sorted the issue, except for the last time when the engine would not turn off (flicked the ign sw a couple of times) and then would not start at all. The engines turns over fine and there is a good spark (so I guess the ign sw is OK), however there is no fuel pressure. I have treid to find out if there is power to the pump but as the ECU only supplies power for 2 seconds (according to the manual) and the pins on the connector are tiny this is difficult.

It would seem that a part from a break in the wire, the problem could be either the Cobra alarm, the crash switch, the ECU or the MFRU (I have ordered a new one as this seems to be a weak item), the pump, or an earth. The fuse looks good.

Not sure if any sensors are in the loop, any other fuses???

Any help in diagonsing would be welcome as access seems to be a nightmare.

Many thanks for any thoughts.

ATB

Clive

[Scuffers]

sounds like a wiring issue...

in order check:

1) inertia switch (Black thing bolted to the LH longeron close to the ECU)
2) then get somebody to turn the ign on whist you stick you head next to the MFRU and listen for the click of the fuel relay (what you waiting for is the click some 5 sec's after the ign as it turns the pump off).
3) the fuse

if all of these are OK, then it's probably the imob, they do this.

if you have a meter, then follow the power for the pump, it goes:

1) starter solenoid (Brown wire with black sleve on it)
2) fuse
3) Engine Harness connector 3 Pin 2
4) MFRU Big plug pin 4
5) MFRU Big plug Pin 1
6) Engine harness conector 1 Pin 4
7) Imob in
8) Imob out
9) Fuel tank harness connector
10) fuel pump

[Go Figure]

Many thanks for the detailed reply. Is there any way to keep the power on as I mostly have to do this on my own and turning the ignition on and off whilst trying to read the meter is a problem? I could use a bulb on a long lead but would rather use a meter to trace the wiring. Also would it be OK to just short our the imob leads for the pump or do you know if this is required by the imob for other things?

As ever grateful for any help.

Rgds

Clive

[Scuffers]

Fuel pump relay trigger is Black-Purple wire in pin 1 of the small plug onto the MFRU.

if you ground this, the relay will click to on, I suggest if your going to do this, use a small pin to stab the wire, then ground the pin.

[Go Figure]

Many thanks for the tip and advice, I'll give all that a go.

ATB

Clive

[Go Figure]

OK, thanks to Scuffers car is now running but I am not sure how!!! Tried to follow the power but got some very strange results so resorted to jumping the fuel pump lines at the alarm plug (white one). Jumped pins 1 and 6 but no chnage so pushed jumper in harder and tried to see if there was voltage at jumper. Car starts, hurray. Took jumper out expecting car not to work, b*****r me car still starts, so not sure what the issue is. Since all this has entailed much pulling of wires and plus. could be:

1. Broken wire.
2. Alarm module is intermittant.
3. Something else?

Anybody else have any experinces with alarm being erratic?

Car is stock T reg S1 elise 1.8 non VVC. New MFRU, all plugs pulled, cleaned and re seated prior to this. Good charge in battery. Problem has been no fuel pressure, engine turns over with good spark.

Grateful for any help as don't want another trip home on the back of a truck.

ATB

Clive

[Scuffers]

alarm modules are somewhat erratic at times, they are not really up to the current draw...

[Go Figure]

Thanks for all the help, I just thought I'd close this with the problem solution (I hope this is the end of it). After fuel pump working, not-working, randomly, I am almost sure I have tracked the problem down to the white plug which connects to the Cobra Alarm module in the engine compartment. It is naturally the most difficult plug to get to and I am not sure if is a broken wire or just a poor pin to pin connection. However, it explains the situation where pushing a jumper into the plug sorted the issue until I tried to put everything back together, and then it stopped I might still get a new module but problem now seems sorted. Just need to tidy things up and stop vibration induced damage - some hope in an Elise engine bay - why did they put all that electronics near a hot engine and exposed to rain etc; the boot would have been sooooo much better and drier!