any engine problems

[rebpvu]

I love my birch white H3 lux pkg. Have had it since November 05. Only have little over 7K miles.
Question? I have a friend who has a 05 or 06 Chev. Colorado with the same engine. At 17K miles he was having problems with engine shuting off. After numerous trips to the dealership he was told the problem was with the valve train. He later learned from other Colorado and Canyon owners they were having the same problem. Dealership told him they fixed the problem but it reoccurred and he finally had to go the the Better Business Bureau and GM. GM is replacing his vehicle, but he is upgrading to a Chev. Sierra.
Anyone having or know of any similar problems with the H3 engine?

[f5fstop]

Some engines had cylinder head problems, usually noted before 15K. The number one cylinder valve guides would wear abnormally. The repair is to replace the cylinder head. Before March of this year, the replacement head was the same as the old one, so the condition could occur again.
After March of this year, the head released for service, or installed on the engine at the plant, has hardened valve guides which solves the problem.
Root cause analysis has not determined exactly why some wear, some don't. Warranty is still not that high on the I-5 or the I-4 engine (same head design).
Symptoms are a rough idle and code P0300+, which are misfire codes due to the valve guide wear. If it fails, it will fail under warranty; unless you only put on about 2K miles a year.
A new repair procedure has been developed that drops the time to replace the cylinder head from 18 hours to 8 hours (no thanks required, it was part of the job:D ). Old procedure required the oil pan to be removed to remove the front cover, new procedure does not even require front cover removal.

[raptorman53]

I don' t know if it's related or not. But, my 2000 chevy silverado used to cut of all the time while i was driving. The machanic said it was my egr valve stuck in the open position.

[deserth3]

I had a 95 Chevy s-10 Blazer. It was notorious for a sticking EGR valve. Soujnded like a diesel but never stopped when the problem occured. Just ran rough as h--l. Finally cured it by getting a gasket with a screen in it.
Oh yeah, truck still running with 200k + miles on the old girl.
I think your mechanic may have been a tad off on his diagnosis.

[f5fstop]

I don' t know if it's related or not. But, my 2000 chevy silverado used to cut of all the time while i was driving. The machanic said it was my egr valve stuck in the open position.

Usually, when coming down from a cruise, if the EGR sticks open, the vehicle will stall. Carbon buildup will keep it from closing many times, just remove, knock off the carbon.

This has nothing to do with the cylinder head issue.

[TomV]

f5fstop, if my truck was build 17-18th April 06 (at least thats what is on all the stickers -on ctrl arms and engine bay etc) - does that mean that the new hardened valve guides are in?

In other words, is there a longer delay between egine production and truck assembly ?

[rebpvu]

Some engines had cylinder head problems, usually noted before 15K. The number one cylinder valve guides would wear abnormally. The repair is to replace the cylinder head. Before March of this year, the replacement head was the same as the old one, so the condition could occur again.
After March of this year, the head released for service, or installed on the engine at the plant, has hardened valve guides which solves the problem.
Root cause analysis has not determined exactly why some wear, some don't. Warranty is still not that high on the I-5 or the I-4 engine (same head design).
Symptoms are a rough idle and code P0300+, which are misfire codes due to the valve guide wear. If it fails, it will fail under warranty; unless you only put on about 2K miles a year.
A new repair procedure has been developed that drops the time to replace the cylinder head from 18 hours to 8 hours (no thanks required, it was part of the job:D ). Old procedure required the oil pan to be removed to remove the front cover, new procedure does not even require front cover removal.


Thanks for all the great info you provided. You definitely know your engine workings. Hope we as H3 owners done have this problem. Again, thanks.

[f5fstop]

f5fstop, if my truck was build 17-18th April 06 (at least thats what is on all the stickers -on ctrl arms and engine bay etc) - does that mean that the new hardened valve guides are in?

In other words, is there a longer delay between egine production and truck assembly ?

Needless to say, engine are built before the truck is assembled. They are manufactured in Tonawanda, NY, tested and shipped to Shreveport for assembly into a H3 or Colorado/Canyon.
There is a date code on the engine...at the rear of the camcover, hard to see, without a mirror.

[montanah3]

:crying: Was getting steady engine light which would come on and go off intermittently. Code was for engine misfire. #3 cylinder is leaking or something to that effect. Being replaced or whatever you do to correct it next week. Was told there is a bulletin regarding this.

[f5fstop]

Yes, we issued a bulletin months ago.
Valve guide wear is the problem. New cylinder head the dealer will install will have hardened valve guides to prevent this from happening again.

How many miles on your vehicle?

[DURAMAX TIM]

A guy I work w/ just had #3 piston sieze up @ 12,000 miles.
I haven't talked to him personally but mutual friend said it's getting a new motor.

[f5fstop]

A guy I work w/ just had #3 piston sieze up @ 12,000 miles.
I haven't talked to him personally but mutual friend said it's getting a new motor.

Different problem. Sounds like one of those, "it happens" type repairs. Nothing on the horizon for siezing pistons, but "sh*t happens." Not the cylinder head issue that the bulletin was issued for.

[cestwick]

Yes, we issued a bulletin months ago.
Valve guide wear is the problem. New cylinder head the dealer will install will have hardened valve guides to prevent this from happening again.

How many miles on your vehicle?

Mine just started getting the p0300 codes in the last 2 weeks. 4600 miles.
Not looking forward to doing this job.

[montanah3]

8600 miles, but started getting the light at about 6000. Brought it to several GM dealers for code. They said it was a misfire, but didn't seem to care about doing anything. Fortunately found a local dealer who will work with my Hummer dealer (across the state) on getting all done under the warranty.

[wpage]

Non Hummer type?:shhh:

[HummBebe]

Mine just started getting the p0300 codes in the last 2 weeks. 4600 miles.
Not looking forward to doing this job.

Heh, does that mean you have do your own warranty repairs:D

[f5fstop]

Mine just started getting the p0300 codes in the last 2 weeks. 4600 miles.
Not looking forward to doing this job.

Not bad with the new repair procedure, using the special tool, and not having to remove the oil pan to remove the front cover.:D
I've done it three times and each time a little faster...got it down to about eight hours, but that included a few breaks and one long lunch.

[cestwick]

Heh, does that mean you have do your own warranty repairs:D

Yes I usually do my own Warranty repairs.

f5fstop] [/B]Not bad with the new repair procedure, using the special tool, and not having to remove the oil pan to remove the front cover.:D
I've done it three times and each time a little faster...got it down to about eight hours, but that included a few breaks and one long lunch.

Bad part about the tool room at our dealership is actually finding a tool in there. I read through the procedure and it doesn't look to bad but I am the main "suspention/alignment" guy at our store and usually get interrupted several times on bigger jobs to do alignments and "set toe" jobs.

[f5fstop]

Yes I usually do my own Warranty repairs.



Bad part about the tool room at our dealership is actually finding a tool in there. I read through the procedure and it doesn't look to bad but I am the main "suspention/alignment" guy at our store and usually get interrupted several times on bigger jobs to do alignments and "set toe" jobs.

The tool to hold the chain in place is new, so they probably haven't had the time to lose it...yet. The valve spring compressor tool, that's been around a while so it might have magically disapeared.
I hear that is the biggest problem for many techs...special tools. Good luck...

[montanah3]

f5fstop
Does this bulletin apply to #3 only, or do I have to worry about having problems with the others. I doubt my local GM has the new tools for a "quick fix", they said to expect 2/3 day repair. Oh well--one of the drawbacks for living in a small population area.:giggling:

[f5fstop]

f5fstop
Does this bulletin apply to #3 only, or do I have to worry about having problems with the others. I doubt my local GM has the new tools for a "quick fix", they said to expect 2/3 day repair. Oh well--one of the drawbacks for living in a small population area.:giggling:

Applies to all on that same engine family, including the 4.2L I-6 and the truck I-4; irregardless of what vehicle it is installed in. As with most OHC engines, the front cover must be removed to removed the cylinder head and to re-install the timing chain. However, on these engines, to remove the front cover, the oil pan had to be removed, as well as all the suspension, drive axles that are under the oil pan. Added about 6 hours to the job.
The new tool allows the tech to retain the chain inside the front cover, thus allowing the cylinder head to be removed a lot faster.
Three days is about the right time. Chances are a smaller dealer does not keep the new cylinder head in stock, plus they have to switch the valves/springs, etc,; from the old head to the new head.
So, a lot of that 3-day time might be waiting for parts; which I believe are readily available from GM service parts.