QuestionQUESTION: Hi after I do a run or when I start the car and idle -- I get a smell of rich fuel mixture -- I have larnt from forums that when starting cold -- it does burn little rich but as it warms up it gets better -- but when I come home and park i get this smell -- any suggestions ?? could it be the MAF or the oxy sensors not regulating for good air / fuel mixture ?? Comments welcome -- Sesh.
ANSWER: Hi Sesh -
I did not quite get if you are smelling a rich fuel mixture in the exhaust, or raw fuel, as if you are at a gas station.
If raw fuel, check the fuel cap for tightness and defective seals. Then follow the fuel lines from the fuel tank and ensure that there are no cracks or breaks in them. Some of those lines are vent lines, and although there is no fuel in them, it does have a very heavy fuel smell if it is compromised.
I did not get the year and make of your vehicle, do you have the CEL on? If there is a rich mixture, the CEL should illuminate and you can determine the source.
Hope this helps -
aloha
calvin
---------- FOLLOW-UP ----------
QUESTION: Hi Calvin -- it is rich fuel mixture smell from exhaust -- NOT raw fuel -- no fuel leaks anywhere -- It is a Nissan altima 1997 GXE -- yes -- i do have the CHECK ENGINE LIGHT on -- car runs extremely smooth -- No misfire nothing -- got EGR all checked cleaned etc etc ( was blocked ) calculated gas mileage with trip odometer gives about 10 kms / litre -- thats good and acceptable -- Temp gauge is at 30 to 40 % level -- Idling REV is close to 750 to 800 RPM -- constant speed RPM is around 2000 or less in OD and a bit more without OD. Aloha -- Sesh.
AnswerHi Sesh -
Best thing to do is have the check engine light diagnosed (OBD). There are several components that could be telling the computer to richen the mixture, including the O2 sensor, and MAP sensor. This way you will know on a dime what to check first rather than guessing.
Hope this helps -
aloha
calvin
