Weak spark

[go-for-it1]

After the winter in hibernation, managed to get my GT2 running at the weekend after cleaning out the fuel system. Took it for a burn up the motorway and everything was fine. Stopped, turned off and restarted ok several times. Booked it in for the MOT today and when I went to drive there the car would not start. After many attempts at starting I gave up when the battery went flat. During this time I whipped out the plugs and turned it over and noticed the spark was pretty weak at all the plugs although a bright blue strong spark could be seen when the HT lead was grounded on the block. Changed the coil, dizzy cap and rotor arm but no start, fuel is flowing through the filter and it stinks of petrol when the choke is out and it floods a bit. The plugs, dizzy cap, rotor arm, leads and plugs have only done about 200 miles, if that. It has a Weber on which was also brand new 200 miles ago. Anybody any ideas? Could the ECU or hall sender or even ignition switch be at fault? How can I check these?

Rob

[Funky Diver]

Have you checked the earth strap?

[go-for-it1]

Have you checked the earth strap?

Will have a look at all the earths tomorrow as I hadn't considered them, Cheers.

[go-for-it1]

Battery to body, body to engine and coil to head earths are all ok, any others I need to check?
Rob

[Nate]

the spark was pretty weak at all the plugs although a bright blue strong spark could be seen when the HT lead was grounded on the block.

which HT lead? the individual ones that go to the plugs, or the king lead (coil to dizzy?)

have you got the correct grade of plug fitted?

[go-for-it1]

which HT lead? the individual ones that go to the plugs, or the king lead (coil to dizzy?)

I disconnected the coil to Dizzy HT lead and grounded it on the block and got a fat blue spark when turning it over, but when grounding a spark plug on a plug lead the spark is yellow and weak on all the plugs.
Plugs are the correct NGK ones, and I have the same weak spark with some old ones I tried, and as I said the car was running great before and the plugs have not been changed since then. Dizzy cap is gleaming inside and out, rotor is the same and resistance on all the leads is correct.
Gonna swop the ECU tomorrow if I get the chance and see if that makes a difference but I would like to be able to test the ECU and Hall sender with a multimeter to discount them before swopping bits over but don't know how!

Rob

[Nate]

ECU? on a GT2? eh?

if you've got a nice blue spare at the lead going in to the dizzy, the fault has to be somewhere after that. check one of the leads off a plug against the block and see what that does.

remember, just because a part is new, doesn't mean it is any good ;)

[go-for-it1]

Fixed it. It was fuel in the end. Wound the mixture screw out a 1/2 turn and it fired up straight away. Took it for a run and all seemed ok! Now Happy!!

[go-for-it1]

[quote : ECU? on a GT2? eh? [quote]
I meant the ignition unit under the scuttle tray by the way!