[FirstBMWLA]

Had this happen twice lately upon startup. Idle hiccups and then begins surging up and down. Get reduced engine power and dsc malfunction.

Here is a video of it.

Last time it did it I was able to clear it up by clearing all fault and shadow fault codes via BT cable. Clearing codes with procede would not do it. It has returned again ~2wks later now.

When it does this throttle is almost completely unresponsive. Barely could make it home 2miles from the gym. Flooring throttle barely gets it going.

Any ideas?
Only code I remember from last time was:
2D09:
2D09 butterfly valve
Error will cause a warning light
Error is currently present
Test conditions have not been completed
Timeout


I'll see what It's giving me this time. probably the same ones. last time there were numerous.


Mods: Procede V5, 50/50 E85 maps, downpipes, dci, eisenhaus mufflers, vrsf intercooler.


Thanks guys

[FirstBMWLA]

Seems cannot get codes to stay cleared this time.
BT tool shows they are cleared but as soon as I start car they are back
and idle is all over the place.

[BMWM.D.]

I'm guessing a crank sensor problem or something with the throttle body.

[FirstBMWLA]

Originally Posted by BMWM.D.

I'm guessing a crank sensor problem or something with the throttle body.

Pulled charge pipe to check if throttle butterfly is moving free or if the chargepipe seal had been sucked into there. Seemed fine.

Have codes
2CEC
2CED
2D09
2CFB

[FirstBMWLA]

Originally Posted by FirstBMWLA

Pulled charge pipe to check if throttle butterfly is moving free or if the chargepipe seal had been sucked into there. Seemed fine.

Have codes
2CEC
2CED
2D09
2CFB

So I finally got all the codes to clear. No clue why i was having so much trouble. Before I had parked the car I got the procede into map0 thinking I needed to. I could never get the codes gone though. I'd clear them, BT would show they were gone. Then if I cycled the ignition power and scanned again they were still there.

It occurred to me last time I had the issue I think i had left the Procede in Map1. So I started the car and got it into map1 with the idle surging all over the place. Then I finally mangaged to get the codes cleared and it cranked and ran fine. Turned off restarted all still fine.

Unrelated but is there not a way to change procede maps if the car won't even start?

I've been getting low battery warnings for a while now. I blamed it on using the parked ventilation feature a lot during the summer and me having a very short commute the battery not getting recharged. Towards the end of the night I had to jumpstart the car to get it going. I left a battery tender on the terminals under the hood all night.

This morning I go to leave for work and all the errors are back. And very shortly after sitting with the ignition on i get low battery error again. Not sure why it wouldn't have charged much over night or any? Didn't have time to scan the codes but I noticed now I'm getting DBC error in addition to reduced engine power and the idle surge etc. Parking brake light is lit up yellow as opposed to usual red. I've seen some people mention the steering angle sensor or something in relation to the DBC error and yellow brake light but no clue how that would affect anything with the crazy idle.
Could any of this have anything to do with the low battery? Kind of at a loss here. Battery is ~1yr8mos old. Registered new battery when I installed it.

[Miller335]

Volts of battery when sitting overnight?

Volts when alt is feeding battery?

[BMWM.D.]

I'm not an expert on any of the piggy tuners, so I can't help you there. I'm not really a fan from an installation / interface point of view, and I'll leave it at that.

I don't think this is a problem where clearing the codes is going to help. That's just a Band-Aid fix anyway. There's obviously something wrong with your car. Low battery voltage can cause all kinds of weird problems, so you might want to start there. Just because a battery is "newer" doesn't mean it can't have a problem. You also might have a draw or an issue with the IBS (battery sensor). Pretty hard for me to diagnose over the internet, though.

On the flip side, an issue with the throttle sensors/motor or crank sensor will also cause DSC warning lights. That's why I originally mentioned those 2 things. The surging in the video sounds like throttle body to me. I think those codes you posted are related to the throttle valve, so you need to start by checking the connection, make sure no moisture is in the connector, etc. Might need a new throttle body.

[FirstBMWLA]

Originally Posted by BMWM.D.

I'm not an expert on any of the piggy tuners, so I can't help you there. I'm not really a fan from an installation / interface point of view, and I'll leave it at that.

I don't think this is a problem where clearing the codes is going to help. That's just a Band-Aid fix anyway. There's obviously something wrong with your car. Low battery voltage can cause all kinds of weird problems, so you might want to start there. Just because a battery is "newer" doesn't mean it can't have a problem. You also might have a draw or an issue with the IBS (battery sensor). Pretty hard for me to diagnose over the internet, though.

On the flip side, an issue with the throttle sensors/motor or crank sensor will also cause DSC warning lights. That's why I originally mentioned those 2 things. The surging in the video sounds like throttle body to me. I think those codes you posted are related to the throttle valve, so you need to start by checking the connection, make sure no moisture is in the connector, etc. Might need a new throttle body.

I have not measured battery voltages yet, I know I should've. I will do that today when I get home. I'll check with car off and running if I can get it running right again. Last night with the car jumped from my 2nd car I finally cleared all the codes and it ran perfectly fine. Restarted multiple times without issue.
I borrowed a friend's battery tender and put that on overnight. This morning all the issues were back and I very quickly saw the low battery voltage warning. Guessing the tender did not do the trick and battery voltage was low again.

I know the code clearing isn't a fix persay it's just odd that one second the throttle is completely unresponsive and once the codes were cleared it all seems normal. Maybe the common denominator in all this is it's fine when batt voltage is ok and goes bad when it's not? Maybe bad alternator. I'll report once I check the voltage. I appreciate everyone's help.

[kiteboy]

Ok i had this and it was only PVC horse which was encrassed!!!
So clean it with brake cleaner put also pvc R&B valve and all it´s ok!!!

[FirstBMWLA]

Originally Posted by kiteboy

Ok i had this and it was only PVC horse which was encrassed!!!
So clean it with brake cleaner put also pvc R&B valve and all it´s ok!!!

Could you elaborate more pls? Do you mean PCV(positive crankcase ventilation)?

[Koreyy]

i had same experienced last month, ended up replacing battery, solved problem.

[FirstBMWLA]

Originally Posted by Koreyy

i had same experienced last month, ended up replacing battery, solved problem.

Thanks, next place I'm looking. Unbelievable a battery could cause these issues. You had the surging idle as well?

[kiteboy]

Originally Posted by FirstBMWLA

Could you elaborate more pls? Do you mean PCV(positive crankcase ventilation)?

Yes ventilation system area motor carter?
Check this....
How many kilometers your car ?

[Miller335]

Originally Posted by FirstBMWLA

Thanks, next place I'm looking. Unbelievable a battery could cause these issues. You had the surging idle as well?

Every type of car behaves differently when battery is low.
I've seen alot worse on lesser cars with a bad battery.

[Koreyy]

Originally Posted by FirstBMWLA

Thanks, next place I'm looking. Unbelievable a battery could cause these issues. You had the surging idle as well?

yes, looks exactly same, i actually kept same battery for a week to see if its the battery and after a week i had to jump from another car to start up everytime i start the car so i figured change the battery, my car is from 08 and never replaced battery before.

[kiteboy]

My car 07 and never replace batery also

[FirstBMWLA]

Originally Posted by kiteboy

Yes ventilation system area motor carter?
Check this....
How many kilometers your car ?

80,000kM

[enrita]

First off remove the tune, clear all codes and adaptions. See if it comes back

[kiteboy]

Originally Posted by FirstBMWLA

80,000kM

So possible...
Check this, mee i had changed pvc horse 24€
And in same time put PVC R&B valve for better aeration...

[FirstBMWLA]

Originally Posted by enrita

First off remove the tune, clear all codes and adaptions. See if it comes back

Ok. Any issue with trying to run without tune and the 50/50 mix in the tank?

I forgot one bit of information I realized. When I was investigating the charge pipe area I found one of the dci cone filters had come completely out of it's coupler. No clue if that had anything to do with these events but definitely not a good thing. When I saw that I thought that may fix things but seemed to have no effect.

[enrita]

Originally Posted by FirstBMWLA

Ok. Any issue with trying to run without tune and the 50/50 mix in the tank?

I forgot one bit of information I realized. When I was investigating the charge pipe area I found one of the dci cone filters had come completely out of it's coupler. No clue if that had anything to do with these events but definitely not a good thing. When I saw that I thought that may fix things but seemed to have no effect.

Empty tank first of course.... And dont mention 50/50 mix just calculate The % of ethanol and take logs. Your trims are probably bad.
Dci has nothing to do .
And seriously battery issue? When engine is on battery has nothing to do with it .

[FirstBMWLA]

Originally Posted by enrita

Empty tank first of course.... And dont mention 50/50 mix just calculate The % of ethanol and take logs. Your trims are probably bad.
Dci has nothing to do .

I haven't logged anything in quite a while. When i first started running ethanol though i did some logging. Fuel trims were in low 20% range I think.