2001 Elantra Bucking at idle

We have a 2001 Elantra GLS with about 98K miles. The car runs fine
when moving, but it has a mild buck at an idle. I usually do my own
maintenance (Plugs/oil). This bucking started about six months ago and
at that time I took it to the dealer as we have the extended warranty.
After scoping it they told me that the issue was two fold. 1. they
replaced the camshaft sensor 2. I had been using aftermarket plugs and
wires and the wires were arching. I replaced the plugs and wires with
the factory parts and this issue has not gone away. I was told by
another dealer that a "deep head cleaning" would correct the issue.
Will this help or might it be something else?

 

I doubt it'll help. Sounds like snake oil. Perhaps ask them if they won'
charge you if it doesn't cure your problem.

Since it's only at idle, I'd recommend checking to see if the intak
manifold gasket is leaking