Why won't my spark plug cap stay on?
The internal grommet isn't gripping the terminal, which prevents the cap from staying seated on the spark plug even when everything looks normal inside. This leaves you stuck trying to figure out why the connection won't stay put.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1replacing the spark plug wires or boot
- 2bending the internal terminal tab closer together with a screwdriver or pliers so it has a good friction fit
In their words
Unedited, most upvoted first, each linked to the thread it came from.
“spark plug cap won’t sit on one of the spark plugs, but it will sit on the other.”source ↗
Kipper_Dog_160 · r/MechanicAdvice · 1 upvotes
“So I did look inside and it looks just fine. That’s why I posted on here because I’m stuck.”source ↗
Kipper_Dog_160 · r/MechanicAdvice · 1 upvotes
“The grommet on the inside isn’t gripping.”source ↗
Bestblackguyever808 · r/MechanicAdvice · 1 upvotes
Where this came up
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