Cly 6 Missfire - burnt valve and broken spring

2005 DC TRD sport 4x4 with only 130k. 160lbs in all cylinders except #6, it has 60lbs. Diagnosis is a burnt valve and broken spring. Wondering how this happens and what my options are? Am I looking at a full rebuild? I just added engine restorer as a band aid until I figure out what I'm going to do with it.

 

Yup, pull both heads and have them redone. Probably a sticking valve broke the spring. If you want to keep it, that's what you should do. If you're capable, pull the heads yourself and take them to a machinist that rebuilds heads and reinstall. Much cheaper.
Good luck with it...but you can't drive that for long with a broken valve spring.
Jeff

 

That's what I figured. Thanks for the input, Jeff.

 

Probably lost a valve guide which lead to stuck valve and broken spring . Time to pull the heads and have it rebuilt . Also if you want to upgrade to aftermarket cyl heads , cams and valve springs for more hp now is the time

 

Ugh, was not really in the mood to spring for a rebuild. Dangit. I thought these things were supposed to be trouble free, haha.

 

I understand your pain, but the lower end is probably fine. As said, if you can pull the heads yourself, you'll save a whack of cash.
Is what it is, I guess...shit breaks sometimes...
Or...it's time for a newer one.
Jeff

 

Yeah, it does, and never at the right time. Oh well, I may just pull them myself.

 

I wouldn’t drive it, hate for that valve to get stuck in the open position enough to hit the piston and now you have more issues. Ditto on what everyone else said. Good luck

 

I'm curious how the conclusion was made that it is a burnt valve and a broken spring.

After all, you are driving a 2005.

 

^^ this..

Have you done a leakdown test?

 

I'm thinking BS.

More likely a blown head gasket in the 2005 model.

What symptoms were you having prior that urged you to get a diagnosis other than the misfire?

Did they pull the valve cover and see a broken spring or are they just guessing?

I wouldn't go just by their one diagnosis. And just for information engine restorer is not going to do anything for either the broken spring or the burnt valve if it does in fact have those. You are only going to do more damage by driving it.

 

Can't disagree with you Jimmyh....either way, the heads have to come off.
Cheers, jeff

 

100 psi light in one cylinder is a little telling though.

 

I trust the diagnosis, the shop doesn't even do rebuilds so they have no dog in the hunt. I think Jeff is right though, either way, heads have to come off.

My symptoms were a misfire basically, both at start up and, it felt like, at acceleration when getting on a highway ramp. Put it on the scanner, 6 misfire, also cats. Replaced both cats, still misfired, swapped coils, stayed on 6, took it to a friends shop where they diagnosed it.