Thunderbolt iv ignition sensor ground wire.

[dwb1957]

Replacing a 28 year old Thunderbolt IV ignition sensor assembly that was 2-wire + a 3rd ground wire that was connected between the bottom of the sensor mounting screw and the TB iv module bracket mounting bolt (@ the exhaust manifold)...The module’s ground wire was also connected to the same bolt.

The instructions for the new ignition sensor says to ground the new 3rd wire at the main flywheel ground point which is not doable without fork lifting the engine cover off. IS THE BRACKET MOUNTING POINT ON THE EXHAUST MANIFOLD AN APPROPRIATE GROUND SPOT?

 

[muc]

IS THE BRACKET MOUNTING POINT ON THE EXHAUST MANIFOLD AN APPROPRIATE GROUND SPOT?

No

They last a lot longer if you ground them in the correct place.

 

[Scott Danforth]

I ground mine at one of the intake manifold bolts. remove bolt, sand the area shiny, install bolt, seal with marine varnish

 

[muc]

I have replaced very few of this new style.
All of them were grounded somewhere other then the recommended place.
Might be coincidence?

 

[dwb1957]

Sounds like it might be worth the extra effort...thanks!