No spark

[Dungman]

First TVR breakdown 13 years in. And it has me stumped.

Using the car no issues, reversing into space and cut out. Assumed I had stalled and tried to restart but no go. Recovery truck home.

Fuel pump primes and starter turns over as normal but will not fire. LED plug testers fitted and show no spark. 12.7 odd volts at both coil terminals. Changed leads, dizzy cap, coil and ignition amp one at a time for spare units kept after previous servicing and still no spark. Managed to snap one of my Accel ceramic leads whilst pulling it off! All relays and fuses good.

94 car with Autowatch alarm / immobiliser, not meta.

Nothing messed with prior to breakdown.

Struggling now, any suggestions much appreciated.

[igiveup]

Top of my head, have you changed the King lead from Coil to dizzy? or checked its sitting correctly?

[Dungman]

igiveup said:

Top of my head, have you changed the King lead from Coil to dizzy? or checked its sitting correctly?

Thanks for the suggestion. Yes swapped king lead but still no joy

[motul1974]

Try checking the swith connection at the bottom of the disi - that's what mine was. It stumped two AA guys before it was found!

[N7GTX]

Hold the king lead from the coil close to the engine and crank. Is there a good strong spark jumping across?
This eliminates a whole load of HT stuff at one go.

[blitzracing]

Its not unknown for the wires leading from the trigger head in the dizzy to break- unplug the amp and do a resistance check in the connector and make sure you are not open circuit.

[PhilH42]

I see you changed the dizzy cap....what about the rotor arm?

[Dungman]

motul1974 said:

Try checking the swith connection at the bottom of the disi - that's what mine was. It stumped two AA guys before it was found!

Thanks. Was not aware of this - how exactly do you get to it?

[Dungman]

blitzracing said:

Its not unknown for the wires leading from the trigger head in the dizzy to break- unplug the amp and do a resistance check in the connector and make sure you are not open circuit.

Thanks. Would you mind putting this in idiot terms? I know how to check for voltage with a multimeter and that's about it!

[Dungman]

PhilH42 said:

I see you changed the dizzy cap....what about the rotor arm?

Still need to try this and the other suggestions. It did not want to come off yesterday. It is a nearly new genuine lard rover item so would hope it's not the culprit but of course makes sense to check.

Many thanks all

[Dungman]

N7GTX said:

Hold the king lead from the coil close to the engine and crank. Is there a good strong spark jumping across?
This eliminates a whole load of HT stuff at one go.

Just tried this and there is a good spark. Still no spark at plugs though

[Penelope Stopit]

Is the dizzy shaft turning when you crank over the engine? If yes - rotor arm is suspect

[blitzracing]

Also worth checking the little spring loaded carbon brush that touches the centre of the rotor arm contact from the king lead connection in the dizzy cap has not fallen out.