Wondering if anyone else has experienced this.

I have a 2004 G35 Sedan. Car is very clean and well maintained, included annual rust proofing. But there would be no reason to apply rust proofing to the gas cap area.

3 months ago, the check engine light came on. Dealer seemed to identify the problem very quickly (suggesting it may be known issue). There is rust around the gas cap area. They did something to remove the rust, and suggested applying vaseline periodically. I took a look at the gas cap area, and while I hadn't noticed this before (my wife drives this car more).. the rust around where the gas cap fits is very noticable. Now the check engine light has come on again, and dealer indicates they can only fix it one more time, as the metal will get worn down when they do this fix. We may have to live with the gas cap issue. I've never had any car show rust in this area.

Anyone else notice this problem?

 

Yup. Kevin suggested I use a rust converter in that area. The sealership fixed mine one time at 90 000 km. but couldn't give me any idea as to why.
It lasted 40 000 and it's bad again. I wonder if the neck ( that's the area that is rusting ) can be replaced?

 

+1 on my car.

 

Whatacar:

I haven't been checking this forum as much over the last year. What rust converter is recommended? I've never used a rust converter before. I was thinking about spraying Krown on the neck, but want to be careful with a rust converter or rust protector, as I was thinking I want to make sure it doesn't get into the fuel tank.

PS. I don't think changing just the neck is possible. Dealer indicates repair would be quite expensive (didn't say how much,... plus it was the wife that took the car in).

Are we just going to have to live with the Check Engine light on? Will it affect Drive Clean tests?

 

I have the same thing. My dealer suggested just sanding it a bit and then adding some grease to prevent the check engine light to come up.

 

check the manual for what is covered by the corrosion warranty.

 

Not a speck of rust here.

 

^^ their problem must be caused from winter driving then, from road salts etc., since you store your red beauty during the snowy months.

 

hey those of you guys in ontario....if you didn know when u go for your drive clean test and thet check the neck for rust ...and if so they cant do the test until you fix it....the stealership is probly grinding it down or something

 

Hi.

I just had my car(a Toyota Corolla) repaired for the exact same problem. Its 5 years old and the check engine light came on. There was rust on the filler neck and the error code came back as:

"P0442 EVAP SYSTEM SMALL LEAK"

This was not covered by warranty so all the dealership did was grind the rust off and reset the check engine light. So far so good.

I don't know how much it would cost in parts and labor to replace the filler neck. Here's a little blurb I googled about that part:

"A Fuel tank filler neck on a car or truck is the long tubular part that connects the gas tank to the gas cap. When you fill your gastank with gas, you insert the nozzle from the service station gas pump into the gas tank filler neck.

On one end, the gastank fuel filler neck can either be soldered to the actual gas tank or can be connected by a rubber hose with hose clamps. On the other end where the gas cap is located, the gas tank filler neck may bolt to the quarter panel, bumper, rear filler panel, or may just stay suspended from the gastank solder.

Many fuel tank filler necks, after time, can become rotted or rusted allowing gas to leak. They may also become bent or distorted from an accident."

 

Is this rust just on the mating surface of the neck & gas cap?
Or is it down inside the neck?

...I've never seen this before.

I was thinking about effects of winter as well Wayne, but if it's under the cap I don't see how salt etc. could cause it.
Maybe trapped vapour?

I'd like to see one of these.

 

I have not seen one either, perhaps someone could take pics.

 

^yeah someone should take a picture.

EDIT: here is mine as a reference

 

If the cause could be established, I'm sure we could come up with a preventive maintenance procedure that would help.
It would be good to prevent it from happening rather than repairing, if we could.

 

could be although if it's inside the fuel neck that's a sealed area and I can't see how it would be affected by environment.

I dont' have the winter salt but on the other hand our climatic conditions seem to speed rust year round. I had my car undercoated and touched up every year but inside/around the fuel filler neck isn't an area that can be covered.