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Discussion Starter #1
I have been noticing that on my M6 occasionally after a drive when i pull up at some lights, the revs will idle at 650-700rpm (as normal) but then climb and stick at 900rpm??? any ideas? is it normal?
 

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Discussion Starter #3
Ok reset adaptions on everything last week, battery is about 3 years old but I can sit watching tv for an hour an it starts fine... Mafs what's the est way to clean?
 

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Ok reset adaptions on everything last week, battery is about 3 years old but I can sit watching tv for an hour an it starts fine... Mafs what's the est way to clean?
If your battery is 3 years old, you should really consider changing it.

We generally use the CRC MAF Cleaner to clean the MAF sensors. Also check your air filters, they might require cleaning as well.
 

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Discussion Starter #5
Hasan, i want to reset the adaptations again as i have new plugs etc, but last time it was going to dealer anyway so they did it, i want to do myself now, how do i do it in DIS? if i cant do in DIS how do i in INPA? its easy on my e39 m5 i do through inpa but that errors on the e3?

Thanks
 

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Pyro225: this is so damn ironic, i just logged on to the site in order to creat a new thread for the same problem and i saw your thread. So thanks for broaching on the subject as I was going to ask the fellow members similar questions.

Basically since i picked my latest evolve tune i realize that 1) idle is higher than it use to be such 500-600 rpm but now it idles at 1Krpm constantly and doesnt drop, 2) the engine obviousluy warms up way too quick which isbt really a bad thing but a bit unusual.
Spoke to Sal as well and he allayed all my worries. So i am not casting any aspersions on Evolve maps as the latest map is the best ive ever had.

I also finally got to use my evolve r cable through the lap top managed to switch it OEM file, yet the idling still persists.

Dropped it at the local dealer and they couldnt find any faults, they also confirmed on the M powered cars you cant adjust the idle valve as there is no such facility, which i dont believe.

Any idea what it could be, i will try follow Hasan Sheikh's advise as a quick step by step solution. can do with cleaning up the MAFs and Filter. battery might be on its way out too. Also last week my oil gauge suddenly dropped to nil and wouldnt pick up the oild reading, i filled it back upp ( slightly over filled up to 1.2L, not worried about that). Dealer couldnt even fault find the oil gauge sensor. weird.
 

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Discussion Starter #7
Im6 my cause was because my car started get bank 1 and 2 to rich faults which was bad mafs, I changed the mafs and the fault went but this high idling persists and that's why I want to reset adaptations... Don't suppose you had the alphan tune did you as that touches mafs? Is yours always high mine is 70% of the time...

Oil is a weird thing i had .8 litres in, drive 500 miles still
Had .8 in drove 300 more had .4 wtf? It burns more
Than my e39 m5 does
M5 1 litre - 1800miles
M6 1 litre -13-1500 miles... Is this the norm?
 

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Oil consumption on the V10 is high and its normal. Do check from time to time your Oil coolers, look out for leaks as they are prone to crack prematurely.

I dont have the Alpha N tune, not too sure about it TBH, i think it will probabaly open up more problems
 

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Resurrecting an old thread. Had the same idling symptoms of late. Car likes to sit at 950-980rpms when engine is hot. Otherwise, it can idle at 780rpm if the car is "not too hot, not too cold". At first, i thought it might have been Thermostat / Temperature monitoring related (fault 2B59). Replaced thermo and this fault has since gone away, but still no dice. After poking around in ISTA, deleted the idle adaptations too [pre-delete was 14Nm normal, 12Nm with A/C] ... seemed to help for like 20 minutes after the adaptation delete [new values after adapt-delete, and self re-adapted became 4Nm normal, 8Nm A/C] , but then the 900+rpm idle came back again soon after. Any gurus might have further info here ?

Much appreciated and Thanks in Advance.
 

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There can be many reasons for this.

1) Might be due to low voltage. How old is your battery? This might be the first indication that your battery is getting weak.
2) Check your air filters and MAf sensors. Perhaps they need cleaning.
3) Re-set the adaptations of your O2 sensors.

Good Luck!
yes, reviving an old thread but no one seems to have found the root cause or have a solution just yet. But @Hasan Shaikh 's suggestion #3 looks promising... time to go digging in ISTA+ ....
 

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Was there any solution to this problem?
Mine is doing the same thing.
After giving it a bit and coming to a halt it will idle nice and calm at 550/700 rpm
But 2 minuets later it will rice up to 900 and more.
I hear a lot of people saying it’s just warming up he cats but no way in hell should it burn as much fuel at idle
You can hear it just throwing the fuel in it’s not good


Sent from my iPad using Tapatalk
 

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OK i ***think*** I've demystified this high idle problem.

Here's what i got so far: plugged in an OBD reader and started logging certain parameters of interest.

Basically when the car idles nicely at 780rpm'ish , ignition timing is approx 16-18deg BTDC. This is pretty standard for most Asian and European motors to idle anywhere from 12 to 18 BTDC.

Then when it decides to idle at around 950 rpm (even when engine is fully warmed up, water temp >85 Celcius and tachometer at max allowable redline indication) , ignition is pretty much close to 0 BTDC (very retarded for idling).
Which made me suspect that the engine is indeed trying to warm up the cats further. Now, since 09/2006, Cat Exh gas temp sensors are no longer used. So the DME is probably "guesstimating" Cat temp or cat performance based on the pre-cat wideband and post-cat narrow band O2 sensors, and then determining some Catalytic adaptation values to be used.

In any case when the engine idles at 780 or 950 revs, A/F still stays pretty much 14.7 (as read from the pre-cat wideband O2 sensor).

Some forummers have suspected faulty MAF sensors but these can be easily ruled out by checking the Filling Adaptation values via ISTA. If the 8-point adapted values for both bank-1 and bank-2 are good (value deviation between 0.98 to 1.02 for all 8 points) chances are the MAFs are still good. If a MAF is going bad, some of the adaptation value points would go awry.... i would think, but i digress.


Also, to consider if the wideband sensors are going bad (or not), I noted its adaptation values to see if they are within the nominal ranges for both banks. Again, if the sensors were failing, an error message would have popped up as well. Furthermore, datalogging & observing the ST and LT fuel trims showed that my motor was initially running rich hence O2 sensor adaptation values were influencing the DME to run leaner in order to get 14.7 . So no dice here as well.

Which eliminates back to just 1 type of adaptation value left to reset, which is the CATALYST adaptation. Before reset, mine were reading 0.2 and 0.4ish . After reset, both were back at 0.1 and the stubborn 950rpm idle seems to have been banished (so far...). I might plug in ISTA to read the cat adaptation values after 2 weeks later and see if the numbers have changed. But so far, so good: no more 950rpm idle even when engine is fully warmed up.
 

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Thanks for the solution. Here’s a question, let’s say I get a tune and decided to get the cold start routine deleted, will that solve the problem as well?
 

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Thanks for the solution. Here’s a question, let’s say I get a tune and decided to get the cold start routine deleted, will that solve the problem as well?
I don't think so. My guess is that the cold-start routine (which lets in more air into the exhaust tract initially) is a function of engine temp aka coolant temp. Whereas the 950rpm idle happens even when engine is fully warmed up, and sound-wise, the cold-start secondary air feed has long since closed up already. You can tell from the exhaust sounds. Also from monitoring the A/F (when it idles high with a warmed up engine) , it still burns at stoichiometric.
 

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OK i ***think*** I've demystified this high idle problem.

Here's what i got so far: plugged in an OBD reader and started logging certain parameters of interest.

Basically when the car idles nicely at 780rpm'ish , ignition timing is approx 16-18deg BTDC. This is pretty standard for most Asian and European motors to idle anywhere from 12 to 18 BTDC.

Then when it decides to idle at around 950 rpm (even when engine is fully warmed up, water temp >85 Celcius and tachometer at max allowable redline indication) , ignition is pretty much close to 0 BTDC (very retarded for idling).
Which made me suspect that the engine is indeed trying to warm up the cats further. Now, since 09/2006, Cat Exh gas temp sensors are no longer used. So the DME is probably "guesstimating" Cat temp or cat performance based on the pre-cat wideband and post-cat narrow band O2 sensors, and then determining some Catalytic adaptation values to be used.

In any case when the engine idles at 780 or 950 revs, A/F still stays pretty much 14.7 (as read from the pre-cat wideband O2 sensor).

Some forummers have suspected faulty MAF sensors but these can be easily ruled out by checking the Filling Adaptation values via ISTA. If the 8-point adapted values for both bank-1 and bank-2 are good (value deviation between 0.98 to 1.02 for all 8 points) chances are the MAFs are still good. If a MAF is going bad, some of the adaptation value points would go awry.... i would think, but i digress.


Also, to consider if the wideband sensors are going bad (or not), I noted its adaptation values to see if they are within the nominal ranges for both banks. Again, if the sensors were failing, an error message would have popped up as well. Furthermore, datalogging & observing the ST and LT fuel trims showed that my motor was initially running rich hence O2 sensor adaptation values were influencing the DME to run leaner in order to get 14.7 . So no dice here as well.

Which eliminates back to just 1 type of adaptation value left to reset, which is the CATALYST adaptation. Before reset, mine were reading 0.2 and 0.4ish . After reset, both were back at 0.1 and the stubborn 950rpm idle seems to have been banished (so far...). I might plug in ISTA to read the cat adaptation values after 2 weeks later and see if the numbers have changed. But so far, so good: no more 950rpm idle even when engine is fully warmed up.
Please update us after two weeks ,,to see if this things you did ( adapt catalyst) work or not.
It will definitely help a lot of us

Thank you.
 

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OK i ***think*** I've demystified this high idle problem.

Here's what i got so far: plugged in an OBD reader and started logging certain parameters of interest.

Basically when the car idles nicely at 780rpm'ish , ignition timing is approx 16-18deg BTDC. This is pretty standard for most Asian and European motors to idle anywhere from 12 to 18 BTDC.

Then when it decides to idle at around 950 rpm (even when engine is fully warmed up, water temp >85 Celcius and tachometer at max allowable redline indication) , ignition is pretty much close to 0 BTDC (very retarded for idling).
Which made me suspect that the engine is indeed trying to warm up the cats further. Now, since 09/2006, Cat Exh gas temp sensors are no longer used. So the DME is probably "guesstimating" Cat temp or cat performance based on the pre-cat wideband and post-cat narrow band O2 sensors, and then determining some Catalytic adaptation values to be used.

In any case when the engine idles at 780 or 950 revs, A/F still stays pretty much 14.7 (as read from the pre-cat wideband O2 sensor).

Some forummers have suspected faulty MAF sensors but these can be easily ruled out by checking the Filling Adaptation values via ISTA. If the 8-point adapted values for both bank-1 and bank-2 are good (value deviation between 0.98 to 1.02 for all 8 points) chances are the MAFs are still good. If a MAF is going bad, some of the adaptation value points would go awry.... i would think, but i digress.


Also, to consider if the wideband sensors are going bad (or not), I noted its adaptation values to see if they are within the nominal ranges for both banks. Again, if the sensors were failing, an error message would have popped up as well. Furthermore, datalogging & observing the ST and LT fuel trims showed that my motor was initially running rich hence O2 sensor adaptation values were influencing the DME to run leaner in order to get 14.7 . So no dice here as well.

Which eliminates back to just 1 type of adaptation value left to reset, which is the CATALYST adaptation. Before reset, mine were reading 0.2 and 0.4ish . After reset, both were back at 0.1 and the stubborn 950rpm idle seems to have been banished (so far...). I might plug in ISTA to read the cat adaptation values after 2 weeks later and see if the numbers have changed. But so far, so good: no more 950rpm idle even when engine is fully warmed up.
Please update us after two weeks ,,to see if this things you did ( adapt catalyst) work or not.
It will definitely help a lot of us.:smile

Thank you.
 
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