Strong fuel smell

[Mark B]

Anyone know why my Challenger has a strong fuel smell 2 mins after I stop driving it? No fuel leaks under the car, fuel pump ok, fuel lines ok, carb not flooding, new petrol cap with no leaks and car running ok. Been like this for the last 6 weeks and stinking the house out.

Any help gladly appreciated.

[Pete]

The only things i can think of off the top of my head is maybe the air filter is getting splashed whilst driving (surges, etc) or possible the emission / vapour device at the rear of the car - see which end emanates the most smell to narrow the search down....

[Mark B]

Thanks for the suggestion.

Also have checked the fuel tank breather pipe and it's working fine.

[TIB3300]

What air filter do you have on it ?

Look for a a small weep of fuel around the carb area, the smallest amout of fuel vaporising when the engine is warm can smell really strong .
Look for any dark patches again around the carb area

[kma176]

I had a similar thing with my Satellite - A steel fuel vapour separator tank and the pipes leading to and from the unit were the main cause. It was tucked up under the drivers rear wing and has 5 pipes going to it, 4 from the fuel tank and one supposed to go to a charcoal canister then to the crankcase breather system .Mine had perforated - then because the fuel cap had vac relief but no pressure relief it just pressurized the fuel tank and pushed out fuel and vapour .

[Mark B]

I had a similar thing with my Satellite - A steel fuel vapour separator tank and the pipes leading to and from the unit were the main cause. It was tucked up under the drivers rear wing and has 5 pipes going to it, 4 from the fuel tank and one supposed to go to a charcoal canister then to the crankcase breather system .Mine had perforated - then because the fuel cap had vac relief but no pressure relief it just pressurized the fuel tank and pushed out fuel and vapour .

Thanks for the suggestion. I think these were only fitted to 440s and 426 Hemi's. Can't seem to find one for a 340.

[Mark B]

What air filter do you have on it ?
Look for a a small weep of fuel around the carb area, the smallest amout of fuel vaporising when the engine is warm can smell really strong .
Look for any dark patches again around the carb area

Think it's a standard air filter, have just replaced it was it was blocked with crap.
No dark patches around the carb.

[kma176]

I had a similar thing with my Satellite - A steel fuel vapour separator tank and the pipes leading to and from the unit were the main cause. It was tucked up under the drivers rear wing and has 5 pipes going to it, 4 from the fuel tank and one supposed to go to a charcoal canister then to the crankcase breather system .Mine had perforated - then because the fuel cap had vac relief but no pressure relief it just pressurized the fuel tank and pushed out fuel and vapour .

Thanks for the suggestion. I think these were only fitted to 440s and 426 Hemi's. Can't seem to find one for a 340.

No rhyme or reason - I had one on my 71' Satellite ,my mates 70' 440 challenger didn't have one but then a 70' 318 challenger did???
The ones I've seen are tucked right up behind a panel behind the drivers rear wheel - I think the give away is to check the breather pipes from the tank normally on the drivers side at the rear of the tank up high . I've been told it also depends on what state they were manufactured for.

[kma176]

s-l225.jpg (6.62 KiB) Viewed 2010 times

This is listed for 70,71 & 72 Challenger

[Mark B]

No rhyme or reason - I had one on my 71' Satellite ,my mates 70' 440 challenger didn't have one but then a 70' 318 challenger did???
The ones I've seen are tucked right up behind a panel behind the drivers rear wheel - I think the give away is to check the breather pipes from the tank normally on the drivers side at the rear of the tank up high . I've been told it also depends on what state they were manufactured for.

Interesting. I've checked at the top of both rear inner arches and nothing. Not near the tank breather and it's not connected to the fuel pump either.

[kma176]

On mine it ran the opposite side of the car to the fuel feed so I don't think you'll find it around the pump or the fuel feed - just have a look around the sides of the tank for any pipes other than the feed or return if you have one .Maybe yours just doesn't have the vapour system after all !!

[ScottyDave]

On my 73 Charger its tucked up between the rear shock xmbr and the tank...but that's probably not a help to you.

[Mark B]

The vapor lines have been sealed so no vapor tank fitted.

Ignore the fuel pipe to tank, there was a leak there a couple of years ago but sorted.

A mate has the vapor tank fitted to his 72 318 Satellite too. Interesting about them being fitted depending on the State.

So the fuel smell is come from somewhere else.
.

[Mark B]

Mike from Tornado thinks it’s fuel boiling in the carb bowl.

Maybe there’s pressure in the fuel line feed forcing fuel into the carb when the car has stopped?

[Pete]

Mike from Tornado thinks it’s fuel boiling in the carb bowl.

Maybe there’s pressure in the fuel line feed forcing fuel into the carb when the car has stopped?

If that is indeed the case, then (assuming hood clearance is OK) it may be worth fitting a non-metallic phenolic spacer under the carb so see if that will prevent fuel boiling.

However, I think if that is the case you would also be suffering other symptoms, such as hot starting issues....

I would also fit clips to the tank's blanked off ports as well.