[460] Gas stains under car

[veegard]

There's this kind of sweet smell of gasoline or more like parafine in the air when I park it..
And I am starting to get some gasoline stains under it when I park it.

My cooling system is 100% tight. The engine has never been leaking or consuming oil.


Possible causes:
Alternator is faulty, it generates correct voltage but almost no current. Most likely brushes are at fault.
Muffler has huge holes in it, will only last a couple of days.
Throttle body and ICV are most likely dirty, causing an irradic idle which usually ends up at 1500-1800rpm when engine is hot.

I know that the Charcoal Canister is faulty, as it does not respond under system diagnostics, and I get an error code for it. How that effects my car I don't know.

I will clean throttle body today and do an oil change. Will get injector cleaner for it when the shop has them back in stock, but they were all out.


I don't really know how any of this can affect actual gasoline spillage.. But the stain was under the middle of the engine bay, so it's most likely from the engine, I suppose... I looked at the two gas lines (turn and return, right?) coming from the back of the car and out on the right rear side of the engine bay. They didn't appear to be leaking anywhere, and all the injection points seemed dry.

Is it possible that an unfinished combustion due to a lack of air or proper spark can make gasoline get in my exhaust pipe, and out a hole in the manifold (if there is one)?
It's a sealed combustion, but still...

It's urgent to get this fixed, because I'm getting a potential buyer for it to come and have a look at it tomorrow!

[B20F]

This leak will probably be the cause of the high fual milage. Check the injectors and the injectorrail for leaks, if the rubberseal around them have perist they can leak and also be responsible for high idle. Will only leak with engine running. And check all the fuel lines and pressure regulator (on the injectorrail) thoroughly. Good luck hunting!

[veegard]

Thanks, B20F.
I tried to look there, but didn't see anything.. But I can't think of any other places where there might be a leak, it doesn't have too many complicated stops and turns.

Cleaned ICV thoroughly, but idle is still crappy. But I got a lot of gunk out!
Tried to clean throttle body.. but I don't get how I'm supposed to accomplish that with no proper equipment and without taking the top off!
Used q-tips, a toothbrush, engine cleaner and a soft cleaning cloth. Got some gunk out, but it didn't seem to make a difference.
I cleaned the air sensor in the intake hose.

I know it's probably in the book somewhere, but diagnosing the MAP and o2 sensor, howto?

[B20F]

You can clean the throttle body like you did. To clean it thoroughly you need to remove it. Only neccesary when real dirty, I cleaned mine the way you did. remember that you will need a new gasket to reassemble it after removal.
Tha MAP sensor can be checked bij measuring the resistance between the connectors, should be 1.3Kohm, voltage is dependent from the vacuum 1,6v-5v. Important is that the vacuum hose from MAP to inlet manifold is airtight. The O2 sensor is the lambda, thought you already checked that one?
Also check the throttle housing for loose connector bolts (airleaks) and check the hose coming from the crankcase ventilation to the thr.body. Remove and clean hose and attachment to it, you can just pull it of. The crankcase ventilation is the cause of the gunk in the thr.body.

[veegard]

Thanks for another portion of your ineffable wisdom!
Too late now, car is sold and new car is bought!
Bought myself an Audi, which hopefully is less problematic!