Smell of petrol

I'd been told that one of my reverse lights wasn't working, so me and my friend went outside and I started the car up and put it into reverse and he stood behind the car to check which side needed replacing. He told me there was a strong smell of petrol at the back of the car. I couldn't smell anything from the drivers seat, but sure enough when I got out and stood behind the car there was a smell of petrol about as strong as you get when you refuel the car. I've also noticed over the last few weeks that the car is going through a significantly increased amount of fuel. Any ideas what the problem might be would be very welcome. I'm pretty able with cars for a first time owner, but I'd really appreciate input from people who really know what they're doing.
 

silento

Ex. Club Member
well the most obvious thing is to get under the car and check for a fuel leak. if that's not the problem then it could be unburnt fuel passing through your exhaust. not sure why though. hopefully someone else will come along with ideas.
 

Scott

My name is Scott
Site Supporter
It could be a faulty lambda sensor and is reading irratically and putting more fuel in. May just be a dirty MAF, trying cleaning it with some carb cleaner.
 

Scott

My name is Scott
Site Supporter
Assuming you have a K11 then ^^^ its in the throttle body. So just remove the airbox and squirt some carb cleaner down into it.

The lambda sensor is located on the exhaust manifold.

Frankspeed.jpg


The plug there on the front leads to the sensor.
 

Scott

My name is Scott
Site Supporter
I would clean the MAF first, alot easier than having to remove the lambda sensor to only realise theres nothing wrong with it
 
Thanks a lot man. Right now I'm just going to assume that it's a fuel leak,since it's the most obvious problem. If that's not the case I'll bear this in mind. Even if none of what you guys are suggesting is part of my problem, I've at least learnt a few things that might be of help in the future. So thank you all. Picture was very helpful. Way easier than trying to explain a metal thing amidst a collection of metal things :laugh:
 

Scott

My name is Scott
Site Supporter
Check the fuel tank for any rusting and also check the filler pipes. Could have corroded a hole in the pipe and its spilling fuel.
 

frank

Club Member
testing the lambda voltage will indicate if its overfuelling, the middle wire should read about .4v to .6v at cruise, and 0v on lift :grinning:
 

Scott

My name is Scott
Site Supporter
oh and if its peeing fuel out somewhere, you would probably notice puddle on the floor somewhere
 
Yeah thanks man. I kinda doubt it's a leak since it's not loosing fuel when it's stationary. It is definitely burning through it quicker while it's being run though.
 

frank

Club Member
its worth checking the ohms on the coolant temp sensor too (if thats faulty it could be effectively like running on full choke eh)
 
am i the only one who thinks its just down to the cold weather? since the car is starting cold and taking a while to warm to an efficent temperature due to the snow etc. the choke will be out alot which will explain the rich smell and the use of fuel will be down to the same sort of thing apart from the fact that you would be starting your car early before driving which you might not normaly do and in some deep snow cases be working your car harder to get through the elements. anyone know what im blabbing on about? :wasntme:
 

RR_dev

Site Supporter
am i the only one who thinks its just down to the cold weather? since the car is starting cold and taking a while to warm to an efficent temperature due to the snow etc. the choke will be out alot which will explain the rich smell and the use of fuel will be down to the same sort of thing apart from the fact that you would be starting your car early before driving which you might not normaly do and in some deep snow cases be working your car harder to get through the elements. anyone know what im blabbing on about? :wasntme:

This is my thought. People seem to be jumping to the conclusion that there is a problem.

The cg engine is a 90's engine remember. It's not the height of efficiency... Not all the fuel is burnt during combustion, you get less than 200ppm (mot emission limit) of unburnt fuel exiting the exhaust. Your nose is sensitive enough to pick this up.

Colder denser air will also be having an effect on fuel consumption.

I don't believe you have a problem...
 
Top