SandMan0987

I have a strong gasoline smell inside the car after I topped off the tank. I could also smell it toward the rear of the car when standing outside. I had to roll down the windows to be able to breathe clean air. After the fuel needle hit 75% capacity, the smell mostly went away. Any idea what it might be? Could it be a ruptured tank. I remember bottoming out my car at 15mph recently, but that didn't seem to have touched the fuel tank. The under carriage was a little scratched/bent afterwards, but I didn't see any scratches to the fuel tank.

EDIT: My car was also detailed recently. The whole engine bay was cleaned as well as the underneath of the car with degreaser to get rid of some oil on engine firewall, transmission, CAT and most of front half of undercarriage ending right before the rear wheels.

laythor

pull up the rear seats and check the fuel tank access ports. one has the pump the other has an access hole only.

drifter_d

Check to see if it's the cat.

SandMan0987

What should I look for in the CAT? I believe there are two CATs in the car. One is covered and the other is exposed. I didn't see any damage to the CATs.

SandMan0987

Pulled up both driver & passenger rear seats, which was quite easy. Both had an identical cover with 4 screws. Opened both and they both had a white plastic thing in the middle with wires attached to them. They both looked identical, but the one on the driver side had some pipes attached to it. I'm guessing the driver side one has the fuel pump. There was some fuel smell, but it wasn't very strong. Any ideas?

laythor

so the fuel smell wasnt stronger there then it's time to check the fuel lines from the tank to the engine since you mentioned bottoming out.

Is it a raw fuel smell or burnt fuel? Raw is leak and burnt would point towards a clogged or leaking cat. Maybe you punched a hole in your exhaust when you bottomed out or knocked a connection loose.

MazdaManiac

iTrader: (3)

Fill the tank up to the top and look again.

drifter_d

^^ What he said! ^^

SandMan0987

Its a raw fuel smell and I could smell even after the car was parked for few hours and we could easily smell it from a few feet away. The gas gauge dropped 25% within 25-30 miles of driving, but has been dropping much slower since then. If there was a leak in the fuel lines, wouldn't it consistently drop until the tank is empty? What are some of the locations where fuel would leak when the tank is full?

MazdaManiac

iTrader: (3)

You were just looking at them.

Do what I just told you to do.

SandMan0987

I updated my post to add this:

"My car was also detailed recently. The whole engine bay was cleaned as well as the underneath of the car with degreaser to get rid of some oil on engine firewall, transmission, CAT and most of front half of undercarriage ending right before the rear wheels."

I noticed that after opening the covers under the rear seat & leaving my car closed for the past half hour, there was some buildup of fuel smell in the car that was easily noticeable, but it wasn't nearly as bad as before.

I will fill up the car hopefully by tomorrow & check for the smell again. I'm thinking that maybe the people who did the detailing could've knocked out one of the fuel lines, but I'm not sure where they're located and how they're routed from the fuel tank to the engine. I looked at the fuel pump again, but couldn't figure out if that's what's causing the smell. I don't see any cracks that are easily visible.

SandMan0987

Update: I topped off my gas tank and immediately saw a big puddle of gas near the fuel pump assembly. Took the car to dealership and they said that the retainer ring and gaskets will need to be replaced, but the fuel pump should be okay. Now I have the following questions:

1. Is it okay to drive the car for a while without repair as long as I don't fill up the tank more than 50% capacity? Will I still smell gas inside? Will the gas mileage drop?

2. What is the best place to find the replacement parts? AutoZone and O'Reilly didn't seem to find them on their computer. The dealer wants $120 for parts alone.

3. What is the disassembly and reassembly procedure? How long will it take? Any additional supplies or tools (I've heard of SST and I'll try to find one).

4. Will the insurance cover the damages since this was caused by bottoming out? Would it fall under Comprehensive or Collision damage? If I file a claim, would it be considered my fault or the parking lot owner's fault?

MazdaManiac

iTrader: (3)

1) "OK" is up to you. I wouldn't feel responsible in recommending that you drive a Molotov Cocktail.
2) MazdaSpeed Motorsports Development, but you need to establish an account. The dealer is your best option, probably.
3) Search.
4) They might, but generally it will fall under collision (and will affect your rates) since you weren't hit by a moving object belonging to someone else. The deductible is probably equal to the repair, anyway.

SandMan0987

I took my car to the mechanic with all parts: Retainer, Union Nut & Gasket. At the shop once I opened the access port cover, I saw fuel leaking out where the hose is attached to the fuel pump. I am assuming that this is what you were referring to. I also noticed that the fuel only leaks while the car is running (which would make sense since there won't be any fuel pumped to the hose when the car is off). Is this leaking from the assembly for sure? How do I confirm that it is not the hose? I'm also wondering if my car always had this problem or if it started leaking from the hose male connector after my car bottomed out.

I saw an Airtex replacement fuel pump at Autozone for $225 (incl. tax) or OEM pump from onlinemazdaparts for $291. Which one should I go with?

How hard is it to remove the hose from the fuel pump? Can I just snap it off or do I need to take off the green clip somehow? I tried looking online with no luck. I'm considering just taking care of this myself this weekend.

SandMan0987

Thanks. I had the fuel pump replaced with the OEM one. All parts replaced are:
Fuel Pump Assembly
Union Nut
Retainer
Gasket

I left the seat off & access port cover open. While driving a short distance, I noticed that it smelled like fuel every time I accelerated hard (engine rpm above 4,000). Could that be related to the fuel lines? I didn't notice any leaks around fuel pump hose connector or the union nut.

I then drove to a gas station to ensure that I could fill up the tank without a leak. Everything looked good after I filled up. I parked my car for an hour & now there's a big leak on the passenger side union nut. This leak wasn't present before. Any idea how it developed? Could the mechanic have screwed something up? I'm guessing that I'll have to replace the Union Nut, Retainer & Gasket on the passenger side as well, correct? Would the sensor on the passenger side have cracked?

I'm thinking about selling this car now after getting it fixed. It doesn't stop breaking down. There's always something wrong with this POS.

SandMan0987

Replaced the Union Nut on the passenger side last night. Didn't replace the retainer or the gasket on this side. Cleared CEL and it hasn't come back yet. Topped off the fuel tank this morning & didn't see a single leak or smell any gas vapors about 2 inches away from each Union Nut.

I read a lot of people complaining about not being able to remove or install the Union Nut, but it is actually quite easy with the right tools (other than the dealer's SST). I didn't try the $17 tool from amazon, but a blunt chisel about 0.8" wide worked the best when hit with a big hammer. I could only tighten to 180 degrees by hand, the rest was done with hammer/chisel. I tried with a smaller screwdriver first, but that was very hard to use.

Thanks to everyone who helped!

rissa_23

I As Well Had A Strong Gas Smell In My Ca So I Took It In And They Said I Had A Crack In My Fuel Pump So They Replaced It But Since They've Done That I Smell More Gas Then Before What CanCause That?

mmmsheen

Hi all, you helped me find my problem with a similar issue -- perhaps others have the same problem as I did.

First noticed gasoline smell inside the cabin about a month ago. Also fuel gauge was going from full to just above 3/4 overnight. I put a full bottle of seafoam in the last tank of gas (1st and last time doing that) before the issue appeared so I had a notion that it was fuel tank, pump, or line related. Took off the drivers side rear seat and unscrewed the aluminum plate to reveal the fuel tank, gas was everywhere. On the cap, and pooling in the "dimples" of the fuel tank.

Per a forum user's instruction I banged the part that Mazda calls the Union Nut (see photos) off with a hammer, screwdriver and about 1000 light-medium taps. As careful as I was, I still banged off 3 of the tabs (do yourself a favor and buy the tool, I'll try to find a link). Once it was off I checked everything out and couldn't find the problem. I did the usual "take it apart, clean it, put it back together" routine that our mechanic fathers taught us -- we all had those, right? :D -- but the problem remained. Still stinky after a few days of driving.

I opened it up again - banged the Union Nut off (much, much easier the second time thanks to a hearty spray of silicon lubricant to the threads - NOT IN THE TANK) and took a look. Long story shortish - I found it was the Union Nut itself, splitting in two. Perhaps the fuel pressure combined with age or seafoam caused this guy to split and spit gas out. Check it out:



And here's one that really shows the splitting - easy to miss:



And finally, fuel system diagram to help you all out, the Union Nut is 42-167:



Good luck, thanks for the help!

mmmsheen

I should mention that after the Union Nut was replaced it drives like a dream and the smell went away very quickly, like 24 hours.

Psyckodoc

Thanks for the diagram. I've been researching this issue. I got an 04 model all stock & original engine. Have had my baby for 8 months. No major issues till yesterday, I filled the tank, got home, and noticed a fuel smell coming from around my side of the car. I'm going to start troubleshooting asap. Will post up the prognosis soon.