What is this?

[kmo058]

I'm replacing the cap & rotor on my '99 2100i and was wondering if anyone knows what the white thing is that is being held down by the 2 phillips screws. Does it need to be replaced when doing the cap & rotor. Thanks for any advice.

[boatwakes]

Thats the ignition sensor module that's prone to failure. Sierra part number 18-5116-1, replace it now so it doesn't come back to haunt you. The new units have potted electronics and don't corrode where the old units like yours can have cracks in the solder and cause interrupted spark or no spark at all. Costs about $40 and should be done on all boats older than 2003.

[kmo058]

Thanks Roatwakes for the info. I purchased the new updated ignition sensor and it has 3 wires coming out of it, a white/green wire, white/red wire and a black wire (see pic of black wire with eyelet & white wires). The old ignition sensor had just the white/green & white/red wire. I'm guessing it is a ground wire. Can anyone confirm this and can you tell me where it is grounded on your Tige' or do I need it at all.

[boatwakes]

Yes, sorry forgot to add that is an external ground wire from the unit. Attach anywhere you see fit on the engine block.