LS2 Ignition Coil

LS2 Ignition Coil




Haltech does not currently sell this part.

The LS2 ignition coil is a high output inductive coil with an internal igniter module.  These were found on most General Motors LS2 and LS3 Gen 4 engines and are commonly used in the aftermarket.
it requires a unique spark plug lead connection that incorporate a ferrule.  Without the correct spark plug lead connection it is possible for the spark to arc to the coil mount body section  of the coil near the spark discharge post.

LS2 Truck Coil Variant

These are identified by a large heat sink.  Wiring is the same as for normal LS2 coils.



Haltech Elite Series Setting
Ignition Mode
Installation Dependent
Ignition Edge
Ignition Dwell Mode
Constant Charge


Charging LS2 coils at over ~5ms can lead to them auto-discharging which results in random ignition timing.  It appears to be an issue with "break" time, the time between firing events.  With high dwell time they will run fine at low rpm, but as rpm is increased issues can be seen. Care should be taken to not overcharge these coils especially at higher RPM.

Suggested Dwell Time for LS2 Coils



Pin Letters are on the Connector Shell
AGround (Cylinder Head)
BGround (ECU Signal Ground)
CIgnition Output
It is advised to Ground both pins A and B to the Cylinder Head to avoid grounding issues causing damage to the coils.


12V Power Supply

The LS2 coil can draw up to 10A.  If high rpm and high power is being used, together with conventional 30A Relays to provide power, it may be necessary to have a separate fuse and relay for every pair of coils.  This is rare but it is possible.

If the wiring is also not cable of supplying the current required it can also limit the spark output.


The number of grounds (2x) on this coil often cause confusion.  If in doubt, all grounds can be joined together and run the to cylinder head.  This can eliminate issues if there is a poor engine ground strap that then pushes high current through the coil.  It can also prevent a coil from firing if the engine grounding is not sufficient, and this happens as the ground lifts on the ECU signal preventing triggering. The fix is of course to improve the engine grounding. 

Ground Pin A should go to the Cylinder Head and is the return path for the spark
Ground Pin B should go to the ECU Signal Ground and is used as a reference for the ECU Ignition Output.

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