Lotus Elan and Lotus Elan Plus 2 Forums

Hi Jay,

the solenoid doesn't have any switched/fused feeds on it so if you wired it 'hot' to the +ve side of the coil then it would surely have powering the coil all the time even when the ignition was switched off?

The exception would be where the solenoid has the extra connection to support a ballasted coil, but that connection is only live whilst the solenoid is engaged during cranking.

Did I also understand the hot wire was allowing the tacho to work?

Iain

Sorry Phil and Iian,

Went for a 20 mile drive and it happended again. Now I am truly vexed.

Jay,

Yeah disappointing of course... we’ve all been there!

Can I check this is what you have:-

The feed to the coil +ve should be from ign switch terminal 2, it’s white, and goes from the switch to the tach, then from the tach to the coil.

On the way it may be routed through the glovebox switch which can give a nasty intermittent problem.

Is this your setup?

Are you getting 12v at the coil +ve with ignition on?

I have seen the white wire insulation melted where there had been a coil problem, that wire needs to be in top condition.

Btw the RVI tach not working with Powerspark is normal, and the Spiyda unit should fix that.
Iain

Thinking about this 90 degree threshold - is that when the cooling fan tries to cut in and maybe creates a short or drops the voltage too low?

Iian,

Thanks for sticking with this. The fan goes on much earlier, at 70c.

"The feed to the coil +ve should be from ign switch terminal 2, it’s white, and goes from the switch to the tach, then from the tach to the coil.On the way it may be routed through the glovebox switch which can give a nasty intermittent problem. Is this your setup?"

Yes, this is the set up. I replaced the glovebox switch with a robust toggle when I rewired the car 2 years ago because the replacement switch for the original looked so flimsy, so I doubt that is the problem.

"Are you getting 12v at the coil +ve with ignition on?"

I will check this out today.

"I have seen the white wire insulation melted where there had been a coil problem, that wire needs to be in top condition."

As I mentioned above, the wiring was redone 2 years ago, but it could have melted sicne. I will check that out too.

Thanks again,

Jay

ideally just after it dies, measure voltage asap!

I’d also quickly pull a plug, earth it, crank the starter and look for a spark.

Does the coil feel hot?

When it’s all cooled down, start it up and warm up the coil with a heat gun or hair dryer, to see if it cuts out.

We can just work through these basics, it’s in there somewhere!

sprintsoft wrote:I’d also quickly pull a plug, earth it, crank the starter and look for a spark.

Or, just carry a plug with you; saves time.