my exhaust stinks of fuel!!

[elvisisgod]

my exhaust gases rally honk of unburnt fuel!!! any ideas ? is the mixture only set by the ECU or has some monkey had a fiddle ? when i bought the car the chav said that you can adjust the mixture useing the brass 'screw' on the passenger side of the fuel rail! made me think hes had a tinker with it , for whatever reason , and buggered things up!!! my car has the ecu port in the centre consol - is it a main steeler job to get the fault codes read ? is there anything obvious/common faults i can check for ? can put it onto a gas analyser to get a co2 reading if that helps! HELP mikey

[Justin]

Hi mate, there is no way of altering the mixture on a T5, its all pre programmed into the ecu, have you got any managment lights on the dash? could be many things, faulty lambda sensor, or just a simple airleak, whats the economy like ?

[elvisisgod]

no management lights on. car pulls nice and smooth , clean idle etc so dont suspect an air leak. economy - to me - is pants but ive never owned a T5 before!! went from dorset to fleet services at night when it was quiet and averaged 20mpg - that was booting it big sty-lee though on the m27/m3 . what is that brass screw thingy ? it does turn ? would playing with it **** things up as it is on the fuel rail!!! do my answers help ? mike

[Justin]

Ok mpg is about right, but if there is a smell of fuel then there must be a problem somewhere.


Where is this brass screw your on about.....?

[elvisisgod]

on the end of the fuel rail just under/covered by the plastic cowling over the throttle body. its about the thickness of a pencil and 3cm long. the car has ahd new cap and rotor - havnt done the leads and plugs yet (cover screw have rounded heads!) occassionally there is a ticking type noise at 3 second intervals from under the dash. think i read on another thread that the fuel pump relay could be at fault causing the engine to run rich to compensate. sound about right ? the car will start about 1.5/2 seconds on the key - could this be the relay not working properly ? i know i should change the plugs/leads first to rule them out thanx mike

[Pedro Fandango]

i think thats just a bleed valve to get air out of the fuel rail

[elvisisgod]

so there is no adjustment on it ? if i make sure it is just done up tight then ? presumably if it is loose/slack then air will be getting in and the ecu will overfuel to compensate for a weak mixture ? sound good or am i talking pants!! mike

[Justin]

No thats exactly right, it needs to be tight or fuel will not be forced at the correct pressures into the injectors, the ecu will demand more fuel and so on.....


Get it tight

[elvisisgod]

i like tight will have a go mike