It's your fuel tank vapour evap system. Nothing to be overly concerned about, just an annoyance
R53 idling fluctuations at stand still
My R53 has developed a new gremlin.
The past month or so Iv noticed when the car idles at stand still for more than 5 minutes or so the revs start fluctuating on the verge of cutting out and then picks itself back up again and down /up etc Temperature gauge is always at half when it's at temperature and the fan is working ( even though Iv only heard it once with the air temp still being pretty cold ) if I rev the car it settles back to normal . It's almost like the car Is running out of fuel . Its had a recent full service including fuel filter .
There's no issues when the car is driving it just seems to be at idle for anytime over 5/10mins waiting for work with the heaters on mainly . I'm abit concerned as its intermittent but probably happening more often in the same situations and I really need it reliable .
Any ideas ?
The past month or so Iv noticed when the car idles at stand still for more than 5 minutes or so the revs start fluctuating on the verge of cutting out and then picks itself back up again and down /up etc Temperature gauge is always at half when it's at temperature and the fan is working ( even though Iv only heard it once with the air temp still being pretty cold ) if I rev the car it settles back to normal . It's almost like the car Is running out of fuel . Its had a recent full service including fuel filter .
There's no issues when the car is driving it just seems to be at idle for anytime over 5/10mins waiting for work with the heaters on mainly . I'm abit concerned as its intermittent but probably happening more often in the same situations and I really need it reliable .
Any ideas ?
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Any chance of anymore detail ? Iv no idea about at that ? Thanks for the reply !It's your fuel tank vapour evap system. Nothing to be overly concerned about, just an annoyance
The evap system takes fuel vapour from your tank and vents it into the intake so it gets burned off. This is controlled by a solenoid purge valve which is located just up from your pulley (the black thing with wires and pipes coming off it). There is also a charcoal canister in the system (under your rear arch liner).
Here's a link to a rather long winded explanation of how it works
BMW and MINI Fuel Vapor Recovery Systems ? Charcoal Canisters ? DIY How To | Bavarian Autosport Blog
Here's a link to a rather long winded explanation of how it works
BMW and MINI Fuel Vapor Recovery Systems ? Charcoal Canisters ? DIY How To | Bavarian Autosport Blog
Spot on ! Thanks m8 , I will now start my research of yet another problem ��
I wouldn't be too concerned about it, mine has done it for the last three years. Chances are the solenoid is fine but the charcoal filter has reached the end of it's useful life
here's a link to the part numbers, the filter is part 20
RealOEM.com - Online BMW Parts Catalog
it could be something else but i doubt it
here's a link to the part numbers, the filter is part 20
RealOEM.com - Online BMW Parts Catalog
it could be something else but i doubt it
As long as if that's the problem it doesn't get me stranded somewhere . might just stuff it full of the charcoal from a fish tank filter at that price though . �� Joke / partly , thanks again for pointing this out . The car has 85k so prob is done .
Same issue with mine, can be quite alarming when it happens!
Scanned it and had a pending fault of post cat lambda sensor, but that was just effect not cause as the readings were alright for the sensor.
Like Astroboy I live with it.
Sent from my GT-I9195 using Tapatalk
Scanned it and had a pending fault of post cat lambda sensor, but that was just effect not cause as the readings were alright for the sensor.
Like Astroboy I live with it.
Sent from my GT-I9195 using Tapatalk
Well I learnt something new today. Didn't even know these systems existed...
Well that's me learnt something new I've been scratching my head about this for awhile thinking of all mad theorys. Fuel filter needs doing thought bit thanks
Sent from my D6603 using Tapatalk
Sent from my D6603 using Tapatalk
The charcoal petrol canister is considered a life time part. I have 217K miles on mine, no issues. Problems with this part usually happen due to improper filling of the gas tank. Never "top off" the petrol in the tank of your MINI......What happens is that topped off petrol can back fill into canister. It not supposed to do that.As long as if that's the problem it doesn't get me stranded somewhere . might just stuff it full of the charcoal from a fish tank filter at that price though . ? Joke / partly , thanks again for pointing this out . The car has 85k so prob is done .
When pump shuts off stop pumping it. This goes for 2nd gen MINI as well.
GL!
If I got it right the vapor valve being stuck open can cause problems at idle (basically a vacuum leak)? So temporarily disconnecting the hose going to the intake from the valve and plugging it shut should cure the problem..?
It's a sealed system so you'll most likely throw a code
Nearly forgot to add. It's not the introduction of vapour that causes the chugging, it's when the solenoid closes and the ecu compensates (as best it can using the reading from the o2 sensor) to the new 'lean' condition
From the link you posted earlier: "A faulty purge valve that stays open all the time can effectively cause a vacuum leak."Nearly forgot to add. It's not the introduction of vapour that causes the chugging, it's when the solenoid closes and the ecu compensates (as best it can using the reading from the o2 sensor) to the new 'lean' condition
Vacuum leaks usually cause problems at idle..? And temporarily keeping the valve effectively shut by plugging the hose should kill that leak.
Yes you're right but they rarely fail. if I get a chance I'll do a quick video of my wideband gauge when it chugs. I know there are no issues with my solenoid
An old discussing I’d like to open back up.
The odd idle surge, I’m dealing with it now - ran the ista+ test to confirm the purge valve is activating and it’s good. Do a live test - let the car run and disconnect the top hose to the purge valve - there’s a lot of suck but no affect on idle, reattach and disconnect the lower hose - the valve will suck on your finger just fine. Idle is perfect.
Next step is to visit the charcoal filter - anyone got a photo of where it is mounted? I’ll blow air from the canister to the purge valve (disconnected of course) to clear the line - check for hose damage whilst there.
A replacement canister is $300 here in Oz from mini - $160 on eBay new, $60 on eBay used.
Anyone had an experience here?
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The odd idle surge, I’m dealing with it now - ran the ista+ test to confirm the purge valve is activating and it’s good. Do a live test - let the car run and disconnect the top hose to the purge valve - there’s a lot of suck but no affect on idle, reattach and disconnect the lower hose - the valve will suck on your finger just fine. Idle is perfect.
Next step is to visit the charcoal filter - anyone got a photo of where it is mounted? I’ll blow air from the canister to the purge valve (disconnected of course) to clear the line - check for hose damage whilst there.
A replacement canister is $300 here in Oz from mini - $160 on eBay new, $60 on eBay used.
Anyone had an experience here?
Sent from my iPhone using Tapatalk
Have you checked all the hoses - the symptoms are also similar to vacuum leak. Mine did this a while ago, and it was the air intake hose that was perished.
My r53 does this occasionally I thought it could be the map or tmap sensor ?
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