I just had a new fuel pump installed. There was not much smell after the first fill-up. But the second fill up produced some gunk on the floor of the garage and after that, no more, not a drop. But the car still smells of gasoline. Could it be the old gas cap? Or what?

Thanks

 

Not saying this is your problem, but if, say, the mechanic got the fuel pump gasket a little screwed up (the one that goes around the fuel pump and seals it against the tank), or if he chipped off a portion of the plastic flange at the top of the fuel pump, gas can leak onto the top of the pump. In some cases you might get enough to leak onto the ground. Why do I know that? Let's just say mistakes were made.

 

Take it back to the mechanic to have him check his work. There shouldn't be any smell inside the car unless the gasket is leaking or a vent hose is loose or off.

 

yes, I think I wil take it back, considering the amount he charged me for the job. Thanks.

 

Did you replace or reuse the seal around the pump to the tank? It is not uncommon for them to leak if you pull the sending unit and put it back in. The lip may not match up, etc. Result is that when you fill your tank full it will pore out on the ground. You should replace this seal with a new one.

 

I unquestionably agree with Boxpin, above. If you can get a new gasket, that's the way to go. Also, I found after installing this gasket more times than I will admit to here, that it worked better for me finally to install the gasket first onto the lip of the tank, and then slip the pump through the gasket and into the tank. Sounds like a nutty distinction, I know, but I found it hard to get the gasket seated correctly if I put it on the pump first and then slid the assembly into the tank.

 

Dear Everyone,
I will do as you advise. There's no gas on the ground where the car rests, so it must leak only when I'm moving, hence no evidence of it. Can it also be the old gas cap?

 

The gas smell is coming from the engine side. But no leaks that I can see anywhere. But the idle is too high (just under 1000 when it should be about 850 or 870). How do you adjust the idle speed on a manual 850? I see the "kick down cable" and all that, but is there a place to adjust?
Thanks

 

There is no idle adjustment, its all computer controlled. If you are idling high you most likely have an intake leak.

 

Dear Boxpin,

Air intake leak? (Is there such a thing as gas intake leak?)

 

Mine was leaking shortly after fuel pump replacement the ring was not fully seated. But took a while to leak. Noticed when the tank was full it would leak fuel. One day it was flowing on the ground, couldn't find it before. Also the vent hoses were cracked on mine I replaced those! As far as idle I would check for vaccum and intake leaks.

 

Yes, air intake leak.

 

Gas intake leak would be more common on a carbureted vehicle. Any loose connection or a crack in a hose between the fuel tank pickup and the mechanical pump that's normally located up at the engine could allow the pump to suck air instead of fuel. Fuel is heavy and more difficult to suck to the front of the engine and any chance possible a pump would suck air instead.
In a fuel injected car it's near impossible for the pump to suck air (gas intake leak) as the pumps intake is almost sitting on the bottom of the fuel tank and the only way for it to suck air is to run out of fuel. If you have an odd one that has a frame mounted pump then once again you could have a gas intake leak as there would be places where air could get sucked in.

On here, almost anytime someone is talking about an intake leak they are talking about a leak of vacuum on the intake side of the engine. Either a leak between the throttle plate and the intake valve or between the mass air flow sensor or baro sensor and the intake valve. The amount of air passing the sensors or throttle plate is critical to the computer as it adds just the amount of fuel it senses is going into the engine and any extra air (the leak) will make the mixture lean and or cause a high idle issue.

 

Dear Kiss,
that makes sense. Not only is the smell in the front (engine compartment) although no visible leaks, the idle is way too high (about 1400 rather than 850 or so) and I was fiddling with the mass air flow meter area before the event. I'll check that area out.

Thanks

 

90% chance its the fuel line that exits the fuel pressure regulator back to the fuel tank.

They have a tendency to leak under pressure when vacume decreases it closes and more pressure builds up in the rail so you dont see it so much at idle.

 

I'm with him. I replaced the regulator with a slightly higher pressure one and had a fuel smell here and there inside the car. Finally found out it was seeping at the line clamps on the regulator. If it has the regular screw style hose clamps make sure you use the proper high pressure FI clamps to replace them. These clamps give a more even seal all the way around the clamp.

 

Thanks for both, B and K. In this case of a fuel regulator issue, need there be amy evidence of a leak on the floor? Or could it be leaking without any evidence of it on the floor?

 

It can be leaking without any of it hitting the floor. It doesn't take much gas to make it smell and when the engine gets warm it helps vaporize it all the more.

 

To what extent is the fuel smell coming from a malfunctioning gas cap? Mine is still the original one (176,000 miles, 850 manual shift).

 

"Air intake leak? (Is there such a thing as gas intake leak?)"

Yes there is. One place would be around the injectors bottom "O" ring where under boost it can blow fuel out.