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Author Topic: petrol smell when cold and judder when cold  (Read 3222 times)

Offline mk5craig

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petrol smell when cold and judder when cold
« on: September 17, 2012, 01:29:29 pm »
Hi all
in the mornings once the car has been stood over night, when i initially start it up theres quite a strong petrol fume smell at the back of the car (more than just exhaust fumes) and when pulling away and driving the first 100 meters when accelerating  gently the car holds back (in a few gears) until you floor it and it clears (roughly around 2000-2500rpm), if you keep gently accelerating it does judder slightly before clearing then it will be fine for the rest of the day.

any help would be great

thanks craig

Offline keano

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Re: petrol smell when cold and judder when cold
« Reply #1 on: September 17, 2012, 09:26:29 pm »
Do you have a de-catted exhuast? Or perhaps a failing cat?

Offline mk5craig

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Re: petrol smell when cold and judder when cold
« Reply #2 on: September 17, 2012, 10:40:16 pm »
Standard exhaust, I did consider the cat, but is there anyway to confirm?
Thanks craig

Offline GrayMK5GTI

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Re: petrol smell when cold and judder when cold
« Reply #3 on: September 18, 2012, 04:44:51 pm »
My advice (and probably backed up by numerous others) is not to floor it when the engine is cold  :ashamed:

Although I can't comment on the petrol smell, it's normal for engines to hold back a bit from cold (all my petrol cars have been like that). I'm sure it's down to the fact that modern engines are designed to run best when warm  :happy2: and when they are "on choke" they never run at their best.

Highly strung N/A engines such as Civic Type-R and Clio 182 are much worse than the GTI for this.

Best just to put up with it and drive gently until the engine is warm. . . Then enjoy  :evilgrin:

(bare in mind oil doesnt get warm until about 10mins after the water gauge is at 90 degrees)
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Offline Timi8888

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Re: petrol smell when cold and judder when cold
« Reply #4 on: September 19, 2012, 09:32:49 am »
I have exactly the same problem as you, and this only started after my cat failed. I cut the cat out, and punched through the wiring, and then welded it back on. I think it is the back pressure being caught in that part of the exhaust system. When fully warm, there are no problems whatsoever.
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Offline mk5craig

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Re: petrol smell when cold and judder when cold
« Reply #5 on: September 19, 2012, 04:37:16 pm »
My advice (and probably backed up by numerous others) is not to floor it when the engine is cold  :ashamed:

Although I can't comment on the petrol smell, it's normal for engines to hold back a bit from cold (all my petrol cars have been like that). I'm sure it's down to the fact that modern engines are designed to run best when warm  :happy2: and when they are "on choke" they never run at their best.

Highly strung N/A engines such as Civic Type-R and Clio 182 are much worse than the GTI for this.

Best just to put up with it and drive gently until the engine is warm. . . Then enjoy  :evilgrin:

(bare in mind oil doesnt get warm until about 10mins after the water gauge is at 90 degrees)

Thanks for you reply,

i dont thrash the car when cold as i dont agree with it either as i understand the damage it can do, i mean when accelarating off the car holds back at around 2000rpm and will not increase until you fully press the accelerater and it clears it self quickly and is fine then (not massive rpm around 3000-3500rpm)

its not normal running after having 5 golfs and working on cars for the last 10years its not how it used to be or should be like,

hope that makes sense  :signLOL:

thanks craig

Offline mk5craig

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Re: petrol smell when cold and judder when cold
« Reply #6 on: September 19, 2012, 04:38:41 pm »
Thanks for your response Timi8888,

when you removed the cat, did you just remove the pre cat or all of it?

thanks craig

Offline Timi8888

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Re: petrol smell when cold and judder when cold
« Reply #7 on: September 19, 2012, 04:40:14 pm »
It was only the catalytic converter, removed all the wiring inside of it, and because this happens now, I reckon it would be something to do with that when it comes to your car?
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Offline Timi8888

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Re: petrol smell when cold and judder when cold
« Reply #8 on: September 19, 2012, 04:42:42 pm »
And also, failed catalytic converters mean the smell of petrol is more pungent, as there is nothing to filter the exhaust fumes. It could also be due to over-fueling, as you may have a faulty lambda sensor? Is your engine management light on?
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Offline mk5craig

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Re: petrol smell when cold and judder when cold
« Reply #9 on: September 19, 2012, 04:44:51 pm »
theres no lights on and dis-regarded the lamda sensor as my mpg is still good and car running fine except this
thanks craig