Its a 99 SSEI Bonneville and it had a misfire on cylinder 3 then it set for a day and then it ran fine and the check engine light went out. The next time it got started cylinder 3 was misfiring again. This cycle just repeats over and over. So we have not a clue what would be causing this to happen so regularly.

bs2
Any help would be appreciated.
Thanks in advance

Get your DTC'* pulled at Autozone. Tell us what the codes are and we can walk you through fixing it.

When did you last change spark plugs? spark plug wires? fuel filter?

Start with checking your plug wires and coils:

https://www.gmforum.com/t278818/

Switch the coil pack for cylinder 3 with one of the other coil packs, and determine if the misfire moves with the coil. If it does, the coil is bad.

If the plugs, wires, and coils are all okay we will check your injectors next.

Let us know what you find.

Here'* what you need to check.

https://www.gmforum.com/t284039/#post1390841

Alright, will do but it might take a few days before we are able and thanks for the input