Hi, i posted this question on another forum. i was just wondering if anyone over here had any insight to share. sorry if double posting is a no no...

"Hi Guys,
Just wondering if anyone has any insight or pointers as to my situation ... or if this topic has been beat to death i aploigize. I did try some searching.

2007 h3. 3.7. purchased 10/06 new. 91,000 miles now.

My truck was begininng to feel like it was going to stall at idle. then it threw the service engine light on start up. the code was misfire cylinder. cleared code. week later light came on again at start up. changed plugs. put good gas in. ran better. week later light came on again. missfire cylinder 1. changed coil 1. then right on start up light came on again. missfire cylider 1. cleared the light. i ordered Techron addative.

my VIN is an early number i think
5gtdn13e
578103113"

THANKS!!!

 

I had the same problem, I have a 2006 H3 and the heads will have to be replaced. First, Call GM and start a service request. They will direct you to go to a dealer and have the test run to confirm. Their is a TSA out for this issues, the dealer will try to charge you around $2,500 for the job. In my case, GM paid for all of the parts and I paid the labor, plus they gave me a rental for the week.

I will have to admit, GM corporate took care of me when they did not have to.

 

is this a problem in just 3.5s or 3.7s too?

 

how did you contact GM for a service request?

 

I have a 3.5 and their is a TSA out for that issue. I called the number in the front of the manual.

Its a known issue. It's and issue with the Colorado's but if your VIN falls within a certain range, they should help you out.

Once you call GM, they will tell you which dealership to take it to, don't let them do anything more than the test until GM corporate tells you their solution. They have the final say, not the dealership.

Let me know how it goes.

 

What problem?

You asked a question, did not post the actual code. "The problem" that so many refer to is only for GMT 355s and 345s with the Atlas L52 (3.5L) motor built before March 31, 2006. That is what is covered by the TSB.

Any motor can have a cylinder misfire, it can be caused by many reasons. Some 3.7s have had cylinder head and valve train problems, but not related to the TSB that was corrected in all Atlas Motors made after 3/31/06.

Unfortunately with your limited info I can't help further.

 

Both my 06 and later 07 had the head replaced, 06 at 15k and the 07 at 70k

 

thanks for all the insight so far. if the light comes on again , when i have my machanic clear it ill write the code down exactly and report back. all i remember him saying was...multiply cylinder misfire, and then misfire cylinder #1. sorry i wasnt more specific.

 

right now im just trying to run a tank of 93 oct through with a bottle of Techron as per my machanics addvice. he said we'll go from there if it throws the code again.

 

See my attachments. This is where GM was able to help.