E39 528i - petrol smell on cold starts

[jeffbebe 1560]

Any ideas on how to locate the source of a fuel leak on cold start ups in my E39? The smells pretty bad but only lasts a minute or two until the engine warms up so I'm assuming it's a seal somewhere that leaks until it's warmed up.

Recently had the injectors cleaned and seals replaced, it's possible I suppose that one of the seals is bad but I thought those seals were to stop air getting in rather than fuel getting out.

If it was the fuel pump seal under the back seat wouldn't it smell inside the car?

Anyway, I'm sure it's not a major but I don't really know where to look or what to look for...

[cliffdunedin 8]

I had a similar problem on my old e36, one of the small fuel lines had perished and was leaking slightly, the smell was being sucked through the air vents into the car... I don't know much about the e39 but could be something similar. Maybe start it cold and have a sniff around the engine bay

[rusteee 52]

Both my E36's were like that, same engine. So I just assumed thats how they were, running rich when cold really stunk of petrol then lean out as they warmed up. The olds E36 323i does the same thing.

[jeffbebe 1560]

Both my E36's were like that, same engine. So I just assumed thats how they were, running rich when cold really stunk of petrol then lean out as they warmed up. The olds E36 323i does the same thing.

Quite a few similar threads on other websites say the same thing but I can't help feeling that, while it might be common for the M52B28 engine, it can't be normal... I mean they didn't stink of petrol on cold starts when they were brand new surely?

Gotta be a seal or something somewhere. Going to see if I can locate it but I'm no expert unfortunately.

[dubman 39]

http://bmwfans.info/parts/catalog/E39/Seda...tion_system/#11

could be one of those hoses perished or untightened connection.

was this after you changed injectors? no clue on e39's but can you see any fuel leaking?

[jeffbebe 1560]

http://bmwfans.info/parts/catalog/E39/Seda...tion_system/#11

could be one of those hoses perished or untightened connection.

was this after you changed injectors? no clue on e39's but can you see any fuel leaking?

Thanks. Yes, was after injectors were cleaned and resealed (professionally not by me). No visible fuel leak and today when I cold started barely detectable smell - which is weird as it's been really strong on other days. Couldn't see any leaks though there was a small amount of residue around injector 1. I've cleaned up the engine and will see if it shows up again.