Yup, already done.

 

Thank you. I was posting and trying to listen to a conversation with the wife at the same time. I have learned over the years that it is not in my best interest to tell her to wait until I'm done with what I'm doing before she tells me something.

 

Couldn't get to the dealer this afternoon - will be there tomorrow morning. Many thanks for the reminder about getting the old parts. More later . . .

 

Make them test the vapor recovery system WHEN IT IS COLD. There are solenoids that can hang up when cold, causing a vapor vent. OBDII requires at least 2 consecutive errors in order to set the CEL.

The solenoids can be tested with a TechII Scanner, by activating them and listening for the click. Also a smoke test for leaks.

 

Went to the dealership first thing this morning. They told me they didn't see gas leaking anywhere -- but they smelled it around the gas tank. I asked if they checked around the engine and they said no - because the raw gas smell was near the tank. They did not pull codes. They told me the fix is replacing the fuel sending unit. They wanted $636 + tax to replace it.

They may be right, but maybe not. I don't have a handle on why a faulty sending unit would only leak on a cold start in cold temperature and correct itself in 1 or 2 minutes. Again - they may be right, maybe not. Their explanation just didn't feel right. I paid their diagnostic charge ($110) and drove the car out.

I'm going to get the car into a shop I know - hopefully before the weekend.
Will run down all the posted suggestions working with a shop I trust. Will post again as soon as I know more. Thanks, all.

 

It is not unheard of that the rubber gaskets on the filler and vapor system crack.

 

I got my car in to a first rate shop yesterday - actually - I left the car Sunday night so they would have the car for a cold start. As luck would have it -- we had a very mild night, so they did not experience the strong gas smell on the start up. Nevertheless, they pulled codes, gave the fuel system a thorough inspection and tested the vapor recovery system.

Regarding the Chevrolet dealer's original diagnosis: - absolutely no evidence of fuel leaking was observed anywhere. They came across nothing that would point to replacing the fuel pump. (The Chevy dealer told me the pump needing replacing right-now immediately.) The owner at the new shop speculates that the vapor recovery system's solenoid might be hanging up in very cold weather -- but as the gas smell always dissipates very rapidly to leave it alone. Perhaps if the car was parked in a confined area there might possibly be some concern. Basic bottom line assessment: the car is A-OK.

He also checked out the other items the Chevrolet dealer said needed immediate right-now attention, i.e. the serpentine was ready to let go and the upper radiator hose was leaking and the housing was cracked. I had looked at both myself and saw nothing. My mechanic said the serpentine was showing normal wear and its condition did not appear to be anywhere near an immediate fail point. He also found no evidence of any leaking anywhere around the cooling system and there was no crack in any housing.

I'm satisfied with his assessment. Just for good measure, his bill was only $107.00. That included the diagnostic time on the fuel system, etc., as well as the tire rotation and rear brake adjustment I requested. His shop is an Angie's List honor roll business and has top ratings from Checkbook.org. The shop is Certified Auto Repair in Rockville MD. Two thumbs up.

Thanks again to everyone for the quality of your responses and your intelligent tips and suggestions.

 

I don't even think it would be a concern in a confined area. Ours did this over the 7+ years we owned it whenever it was cold enough. It reaches the 30s a few times a year here. Above that temp; no gas smell. My wife would start it in the garage. The smell didn't linger; it dissapated as the car warmed up as pretty much went with the car as she backed it out. I can't blame you for pursuing this because a gas smell is a concern but I concluded that it was normal about 6 years ago and never looked back. Others seem to verify that: