pt cruiser burnt valve

What would cause a burnt exhaust valve on #4 cylinder on 07 PT cruiser with only 57,000 miles?

Piss poor factory valve job. Not that uncommon on the 2.0 and 2.4 engines. Ive seen a bunch, especially on the 2.0 neon engines.

Is that a confirmed diagnosis? We have done a ton of Mopars with 2.0 and 2.4 engines. I can't remember the last burnt ex valve I have seen. I'm not saying it doesn't happen, I just haven't run into it.

I'ld certainly make sure that was the problem BEFORE tearing into it.

It could have been overheated. I know of one like that, has a slight roughness @ idle. One of the exhaust valves/seats is bleeding off some pressure.

When I worked at the dealer it was common on the later, say 04 and up engines. If they were not totally burned and zero compression, one hole would be down at least 40 or more psi causing the engine to trip the misfire monitor.

Sorry to say but it is fairly common for those and the 2.0 to burn the exhaust valves.

It had number 4 misfire and low compression on that cylinder. Never overheated. Car ran rough for a while. Car is apart and the head is at the machine shop. I did some online searches and it appears to quite common even on low mileage PT`s. Just looking for ways to try and prevent it from happening again. By the way, we had a 03 Neon with a 2.0 with 168,000 on it and it never had any internal engine problems.