Hello,

It looks like the head issue was the early on builds. Has anyone had this with an 08 truck?

About 3-4 weeks ago, I started noticing a tapping every time when I first start the engine, then it would go away after about 30 seconds to 1 minute of running. Then about a week after I noticed that, after driving and coming to a stop the car idle would be completely random and the car would shake and feel like its going to stall, although no apparent loss of power when giving it gas and starting to drive again. Then after about a week of that, the idle fluctuations stopped, but the ticking continued. Once when it was very bad, I hit the onstar button to see if they could run a diagnostic, which they did, but nothing came back. Never any lights on the DIC either.

I took it into the dealer about a week ago, and of course I couldnt reproduce the idle issue, and they kept overnight and acknowledged the ticking, but said its normal within range so no need to do anything.

This morning when I left, I came to a stop sign at the end of the road by my house and sure enough the idle dipped and the truck shook a few times, but that was it, then it didnt do that anymore, so I am at a loss with this. Its the same kind of feeling I've had on older vehicles where a sparkplug wire was going bad, and on a damp day you would have that occasional miss.

This is a bit annoying to say the least, as the car has 14k miles on it, and its got a tapping on startup, my 86 mercedes with 200k on it didnt do this.

Any thoughts out there, on what I can do or tell the dealer?

Thanks a lot!
Josh

 

There have been a couple members that did not have the 2006 head issue, but did have a problem with a defective valve spring?? You could pull off the Throttle body resonator box and make sure all the coil packs are tightly and correctly on all five plugs, or have the dealer check that when you tell them it sounds like a bad valve spring to you and they should do more to diagnose the problem. Good luck.

 

I am seeing head and valve issues on 2008 H3s. Though not as early in miles as your is. All the ones I have right now are around 30K.

 

Hi jrbnc, I was wondering if you ever found the problem with the miss?? I have to same problem with my 08 H2 .

https://www.hummerforums.com/forum/h...-engine-32802/