Getting new head

[H3 Alaska]

Originally Posted by f5fstop

Usually, sulfur kills the fuel sender unit. Different areas of the country have different amounts of sulfur during different times of the year; due to different requirements for fuel. Sulfur destroys the contacts on the sender unit. Usually, when it fails, the gauge will say Empty, even if the customer has just filled the vehicle. Prevents people from being stranded.

It is not just GM. My Jeep had a sender replaced at around 12-13K, and I have never had a sender replaced in a GM, but I know many who have. The fuel senders are not manufactured by GM, the supplier, supplies many car companies the same basic sender.

F5 I have no scientific data to back this up, but it?s interesting you mention it.
All 3 of ours (our 2 and the brother in law) had the misfire issue pop up right after ?winter fuel? was issued here in Anchorage.
Also, my first thought was that the change of moisture in the air was a contributing factor. We had mega rain in the fall, and it was constantly wet. I was wondering about this due to the way the intake of air is directed into the air filter housing.

Also if you remember me mentioning the issue seemed to happen on mine originally when the ?low fuel? light came on.
This points me (again, with no scientific data to back it up) to fuel tank/air/road moisture.
I constantly run my tank to the low fuel light while in town as a side note.

All of our fuel up here comes from AK crude produced in 2 or 3 refineries.
I?m using Chevron regular 95% of the time, the wife and brother in-law are random fillers at wherever they feel like it.

Mine is going back in again on Monday for another P300 code if they want to use it as a case study.
Feel free to contact me for dealer details/release/etc.

Dan

[deserth3]

Last month I drove up to Edmonton Canada. WHile up there the check engine light came on. Onstar said it was related to changing fuel, fuel cap, ect. I don't remember the code.
The engine light went out when I got back to the states and ran US gas through it. I did a little reading on the internet. Canada still uses MMT during the winter which is not recomended according to the owners manual.
While in Canada I only used ESSO and Chevron. Of course nothing on their pumps stated what additives were used.
I just got the onstar email and everything is good.
Just a thought...Any comments or problems from Canadian Hummer owners?

[deserth3]

Scratch what I said about fuel. Went in for new roof rails today. SHe's staying getting new head.
What's interesting is it didn't show up on the diagnostic email I recieved yesterday.

[Idaho-Hummer]

man that suck. Hope the roof rails work out better then the head.