Smell gas fumes by filler cap

[89Suburban]

I have noticed the smell of gas by the left rear of our 2007 Tahoe 5.3. There are no codes being thrown. Sometimes it takes a few extra turns of the starter to get it to run, but not always. No evidence of gas leaks that I can see, or on the ground. Any ideas?

I have been going through this for over a year. I had it up on lifts in the spring and inspected by myself and other mechanics. Reached all over the top of the tank and couldn't find ANY dampness or fuel residue. No evap codes. Really irritating.

This fall it got really bad. I had visitors to my house mentioning the smell, I had people calling my work because they smelled gas near the truck. I climbed up under the back with a shop light and my cell phone and finally got a snapshot of the sending unit and surrounding area that is soaked. So either I have a bad hose connection, leaking o-ring seal, or it is rusted and leaking through. I am fairly rust free for a PA truck as well.

Still in my planning phase of how I am going to move forward in resolving this. Still in the investigative phase. A scope would be really handy right now.

 

[Geotrash]

I have been going through this for over a year. I had it up on lifts in the spring and inspected by myself and other mechanics. Reached all over the top of the tank and couldn't find ANY dampness or fuel residue. No evap codes. Really irritating.

This fall it got really bad. I had visitors to my house mentioning the smell, I had people calling my work because they smelled gas near the truck. I climbed up under the back with a shop light and my cell phone and finally got a snapshot of the sending unit and surrounding area that is soaked. So either I have a bad hose connection, leaking o-ring seal, or it is rusted and leaking through. I am fairly rust free for a PA truck as well.

Still in my planning phase of how I am going to move forward in resolving this. Still in the investigative phase. A scope would be really handy right now.

There's prolly only one solution: drop the tank and put in a new pump with new o-ring. Comes with all new elbows and fittings. Probably best not to attempt to cut an access hole as some have done. The sparks from the cutting wheel mig....BOOM! And I kinda like having you around here.

 

[89Suburban]

There's prolly only one solution: drop the tank and put in a new pump with new o-ring. Comes with all new elbows and fittings. Probably best not to attempt to cut an access hole as some have done. The sparks from the cutting wheel mig....BOOM! And I kinda like having you around here.

Drill bits and sawzall blades should be safe enough. And I can jamb the echo leaf blower under there on full blast too.

 

[Fless]

The tanks aren't all that difficult to drop down if you drain a lot of the fuel, just watch out for that over-the-crossmember evap line!

 

[GREGB1954]

I decided to take it to the dealer as my mechanic punted on it. They found it right away and is as 89Suburban describes it: Leak was around the fuel pump. Wiill replace the pump and 2 lines that connect to it as the connections are frozen. $1600 OUCH! I remember when fuel pumps were $25, 2 bolts, and 2 hose clamps. I can't complain though as it has been a pretty solid 15 year old vehicle. Appreciate the help, folks.

 

[Geotrash]

I decided to take it to the dealer as my mechanic punted on it. They found it right away and is as 89Suburban describes it: Leak was around the fuel pump. Wiill replace the pump and 2 lines that connect to it as the connections are frozen. $1600 OUCH! I remember when fuel pumps were $25, 2 bolts, and 2 hose clamps. I can't complain though as it has been a pretty solid 15 year old vehicle. Appreciate the help, folks.

Glad you got it fixed. Curious why your mechanic punted though. I’d find a different mechanic to go to for my future work if he cost me $800. Parts and labor on that job should run about $800 from and Indy shop - and that’s with an OEM pump. 1600 - 800 = $800 more than it should have.

 

[GREGB1954]

Glad you got it fixed. Curious why your mechanic punted though. I’d find a different mechanic to go to for my future work if he cost me $800. Parts and labor on that job should run about $800 from and Indy shop - and that’s with an OEM pump. 1600 - 800 = $800 more than it should have.

They dropped the price by $200 probably because I told him they were overpriced. They ran into difficulties with trying to get the lines off so they at least put some extra hours into it. My non-dealer mechanic is about as old as me and he likely did not want to drop the tank, don't know for sure. It's fixed and good for another 15 years and 100k miles.

 

[89Suburban]

DAMN THAT'S RICH!!!!!!! Time to get my sawzall out!

 

[GREGB1954]

DAMN THAT'S RICH!!!!!!! Time to get my sawzall out!

Don't forget to cover the hole when you're done.

I actually helped my son change his fuel pump on his 2016 Chevy SS. We had access to a lift and he is more fearless than I. I took about 3 evenings to RR the pump. Not that bad given the $$ staying in his pocket.

 

[Fless]

I know that your GMT900s are a bit different, but not hugely. Plenty of YouTubes out there.

Did my 04's twice, with the diff on some large jackstands, in a few hours. The second time I prepped everything like removing all of the evap and fuel filler connections that needed to come off, and my son helped me drop it the next day. Not that awful. My frustration is always with the evap connections, but once I study them for a minute or so they're just a wrestling match that I win. Here it is after I prepped it, ready for the tank to be dropped.




Get crackin'!