I just fill up my tank (no fuel leak), but after I park the car and shut off the engine, I notice a small amount of fuel dribbling near the gas tank (It happened after I shut off the engine, when the engine still running no leak), After I clean the spilled fuel (About 10-20 cc), there are no more leak/drip, the next day I drove the car for about 10 miles and then the Lambda indicator on dashboard turns on. The engine running normal, no sticky throttle feel, no hicups.

Please Help

 

You might have a rubber hose on the top of the tank leaking.
It is common on the 850's might be starting on the S70's

Have you had any work done on the fuel tank?

 

no I haven't get any work done on the tank, FYI, it only happen if I top off the tank and the leaking start after I turn off the engine, is the lambda indicator on the dash turn on because of this problem or there is another problem with the car??

thank you very much Tech, you always very speedy answering our problems

 

It could be on because of it.
Sounds like one of the hoses are cracked. The computer runs a test to make sure the Vapor system of the car is sealed.
If it isn't then it will throw the light on.

 

Dear Tech,

today I check the fuel tank, there is no cracked hose, but I notice the fuelleaking from border of fuel tank andthe round black plastic on the top right side of fuel tank (fuel pump?) is it the seal? is it possible just to change the seal or I have to change the whole fuel pump?

FYI, I notice that the fuel is leaking from that border of the fuel tank and fuel pump (?) only after I turn off the engine, this is happened after I top off the fuel until it is over flowing, and I just only use the car for 15 miles after that top off

Thank you very much for your time Tech, I appreciate it a lot

 

Maybe just the seal. But look good with a Mirror above the pump. There should be one more hose above the sending unit. There should be another access panel you could look through as well.

 

Dear Tech,

I have opened the metal panel on the luggage compartment's floor that give access to the top of the fuel pump sending unit, there are no fuel leak from the two rubber hoses or crack, but I notice, after I cleaned the top of sending unit, I crack the engineon anfthen I turn off the engine after a while, I notice the fuel is sipping from the place between sending unit and top of the fuel tank, could this be a bad sending unit's o-ring/gasket? ( the fuel in the tank is full)

Is the sending unit' o-ring/gasket could be purchase separately without the whole fuel sending unit? how much approx. price for the o-ring?

Is this problem could trigger the Lambda indicator to turn on?

thank you very much for your help Tech, you have helped me a lot

 

Yes you can buy the gasket seperate.
Should be pretty cheap maybe $20.00 Max.

If it leaks gas it can leak air and Yes make the Lamba light come on.