Problem: Throttle Body changed 3x

[b2ke]

In October my car went into an engine failsafe mode + DSC light came on. The next day high idle symptoms and codes P0221 Throttle/Pedal Position Sensor/Switch "B" Circuit and P0120 Throttle/Pedal Position Sensor/Switch "A" Circuit appeared

Ordered an n62 tb a few days later from eBay which worked perfectly all through November. Now exactly 1 month and 1 day later the engine failsafe mode + DSC light has reappeared along with a high 1k rpm idle. No SES light yet. And of course, just my luck, it is 1 day past the 30-day eBay seller return window.

I have a receipt that the previous owner already had a BMW dealership replace the throttle body roughly 25k miles ago, about 3 years ago. I'm assuming this is the tb that I replaced back October.

Lots of updates throughout the post, but here is the latest....
12/17
Refunded for the used ebay n62 tb and bought a new n62 tb from FCPeuro. Drove fine for a week. Now I'm getting error the SAME 117 and 119 and now multiple misfires (cylinder 1, 2, 7).

oops maybe the n62 tb off ebay was fine

[Chedley]

What are the error codes this time ? Still the same ?? which tool do you use to scan the errors ??
The "failsafe" mode and the DSC light indicate that the problem may not be with the throttle body.

[H3adBussa]

I'm not sure if the n62 suffers from some of the same plagues as the m62tu, but I had a very similar problem which turned out to be oil in my engine wiring harness causing havoc on the DME. The oil had made its way up to the DME through the vanos solenoid connector. Then it pooled on the DME and started to spread to other connectors on the same wiring circuit. Even had oil coming out of the fuel injector and crank sensor harnesses. I replaced the engine wiring loom completely, then cleaned all components which the oil had gotten to and no more issues. I've never run into anyone who had oil wick its way up to the DME but there are several stories of a thermostat housing (with the electrical connector on it) allowing coolant to wick its way up to the DME and frying it.

Can't say this is your issue but it can't hurt to check your wiring for contamination. Completely free to check them at least.

Also, you have an electronic tb right? Are the locking clips still on the pigtail that hold the connector on to the tb? Mine were broken and caused the engine failsafe and potentiometer codes prior to the oil contamination issue. I had a local indy replace the harness. I found it hard to find the correct harness so that route was easier for me.

Good luck!

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[MotorMouth93]

Pull the codes, if they're throttle body-related then sounds like the replacement TB is bad. Who knows how many miles were on that used TB, buying parts like that on Ebay is a roll of the dice and not worth it for something as critical as the throttle body.

[MSporting]

I’ve replaced my tb twice this year - once in February and again in October. I experienced high/erratic revving at idle on startup, and Engine Failsafe shortly after both times.

I bought the first replacement from FCP Euro, so I was able to replace it for free in October thanks to their lifetime warranty on all parts. Buy from them for something like this and it’s not that big a deal to have to replace it again down the road.

I am nervous about what would cause two throttle bodies to fail on my car in such a short amount of time, and I’m interested to find out what you learn about your situation.


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[b2ke]

What are the error codes this time ? Still the same ?? which tool do you use to scan the errors ??
The "failsafe" mode and the DSC light indicate that the problem may not be with the throttle body.

When this problem first appeared in October I used a generic OBII scanner. It read the codes p0221 and p0120 as mentioned in my original post. Some research led me to replacing the m62 tb. I used this opportunity to snag an n62 tb off eBay. It fixed the problems but here I am 30 days later with the same symptoms. Not sure if the error codes are the same because no SES has appeared yet to use the OBII scanner. However....I have just downloaded and used INPA for my first time :D


Three errors; one for my t stat and then two errors 117 and 119. I'll do some searching online for solutions but here they are to update you guys.

Thanks :)



Also, you have an electronic tb right? Are the locking clips still on the pigtail that hold the connector on to the tb? Mine were broken and caused the engine failsafe and potentiometer codes prior to the oil contamination issue. I had a local indy replace the harness. I found it hard to find the correct harness so that route was easier for me.


Pigtial connector is new. Removed m62 connector and spliced n62 pigtail to the respective m62 wires. I'll double check if it's properly seated though.


Pull the codes, if they're throttle body-related then sounds like the replacement TB is bad. Who knows how many miles were on that used TB, buying parts like that on Ebay is a roll of the dice and not worth it for something as critical as the throttle body.

Yeah, hopefully this is just a case of 'you get what you pay for' so I can order a new tb with no further issues. At the time I was ready to pull the trigger on the $300 n62 tb kit off ECS. But a friend, who has done the upgrade as well, informed me these tb's can be had for a mere $50 so that's what I went with lol.


I’ve replaced my tb twice this year - once in February and again in October. I experienced high/erratic revving at idle on startup, and Engine Failsafe shortly after both times.

I bought the first replacement from FCP Euro, so I was able to replace it for free in October thanks to their lifetime warranty on all parts. Buy from them for something like this and it’s not that big a deal to have to replace it again down the road.

I am nervous about what would cause two throttle bodies to fail on my car in such a short amount of time, and I’m interested to find out what you learn about your situation.



I have just recently started buying from FCP actually. In my case I'm hoping the problem is that I purchased a used tb with unknown condition that just happened to crap out on me. However, the previous owner replaced the tb only 25k miles ago, I'm unsure on their lifespans and that seems very short to me. Which is why I posted to see what other's think. I hope you don't encounter anymore problems:)


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[Chedley]

....
Three errors; one for my t stat and then two errors 117 and 119. I'll do some searching online for solutions but here they are to update you guys.
...
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On your car E39 540, the tstat and the throttle are electronically controlled.
The fact that you have errors on both, leads to me to think that the problem is a connection issue. So, as H3adBussa advised above, recheck your connections, harness,..and make sure they are clean, tight and not corroded. The tstat connection is known be problematic, as it can get corroded with spilling coolant, and that usually requires replacing the whole tstat.

INPA Error 117 indicates a problem with the throttle potentiometer signal . And Error 119 indicates a problem with plate #2 of said throttle. So, there may be a problem with the throttle body itself, but I doubt.
BTW, why did you transplant an N52 throttle onto the M62TU ? Could not you find a used E39 throttle...and what was wrong with the original throttle body anyway...Just curious.

Also, as you have the "failsafe" mode message, are there any errors reported from the transmission module ?

Here is what I would do:
-- Recheck the connections, harnesses, splices..etc. of that throttle body. and of the tstat as well. Make sure they are clean, tight, well seated and not corroded
-- Clean up the throttle body -if not done already-, and reset the adaptations: You can use INPA, or the manual key trick (Key in position 2 for 31 seconds)
-- Reset all errors
-- Make sure the battery is fully charged
-- Test drive, then scan again for the new errors.

Keep us updated on what you find.
And as you have INPA all set, you can forget about all those OBD-II scanners.

[b2ke]

Keep us updated on what you find.
And as you have INPA all set, you can forget about all those OBD-II scanners.

Thank you for the very informative reply. I will do as you suggest tomorrow morning.

I replaced the original tb in October because of these symptoms:
- first the engine failsafe prog warning + dsc light appeared followed the next day by...
- high idle between 1-1.5k rpm
- low idle, even stalling when clutch engaged at a stop
- OBDII codes P0221 and P0120

Instead of purchasing a new tb I asked my buddy to see if he happened to have one I could borrow, just to be sure it was the tb. Luckily he did, however, he suggested I upgrade to an n62 tb instead. After doing some research I figured, why not? Its about the same price as a new m62 one. He then informed me he actually purchased his off eBay and after seeing the price difference I went ahead and ordered the used n62 tb. New n62 tb fitted to m62tu worked well all through November until this past evening.

Also the previous owner replaced the battery 5 months ago. But I'll look into INPA tomorrow about the batterry and any other reported errors for the "engine failsafe mode"

This is my 2nd 540, iirc. years ago on my first one had the same 140 error and replacing the tstat solved that. I have actually recently read a lot about the lower temp tstats for our cars, I may look into going that route as well.

Again, thank you Chedley.

[MotorMouth93]

I’ve replaced my tb twice this year - once in February and again in October. I experienced high/erratic revving at idle on startup, and Engine Failsafe shortly after both times.

I bought the first replacement from FCP Euro, so I was able to replace it for free in October thanks to their lifetime warranty on all parts. Buy from them for something like this and it’s not that big a deal to have to replace it again down the road.

I am nervous about what would cause two throttle bodies to fail on my car in such a short amount of time, and I’m interested to find out what you learn about your situation.


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Did you buy the “OEM” VDO TB or the “Genuine BMW” VDO TB? There are stories of the VDO branded parts being significantly lower quality despite being the same manufacturer.

[b2ke]

Update

12/2:
Before starting the car I,
- cleaned the TB
- did the adaptation reset procedure with the key in ignition
- lastly cleared error memory with INPA.

Car started okay and for the rest of the day would idle between 500 and 1k rpm but drove fine.

12/3:
Today idle returned to normal at 500. However the car felt sluggish on hard accelerations. Finally the SES light started blinking and appeared tonight.

Error memory showed:
- again the 140 tstat error
- new 50 and 62 error which corresponds to OBDII p1343 which is misfire in cylinder 1 with fuel cutoff.

I checked the tstat wiring and the dme. No signs of coolant.https://uploads.tapatalk-cdn.com/20191204/5f03dd3271887f063107a4212133e75c.jpghttps://uploads.tapatalk-cdn.com/20191204/5220e381996fe3879699cee85a00bbf9.jpg

Then I checked cyl. 1 plug which looked fine. And then swapped coil 1 and 2. Finished late tonight so I will start the car and check if the error follows the coil, tomorrow. https://uploads.tapatalk-cdn.com/20191204/d8e137b14b622ef5745705cb2cc03b34.jpg

Anyway, I just wanted to update you all on my progress. I'm still quite confused right now as to how it went from TB related errors to a misfire in cyl. 1. But we will see what happens tomorrow when I scan the car again.

Did you buy the “OEM” VDO TB or the “Genuine BMW” VDO TB? There are stories of the VDO branded parts being significantly lower quality despite being the same manufacturer.The N62 tb I believe is "genuine bmw" vdo (has both logos).



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[MSporting]

Did you buy the “OEM” VDO TB or the “Genuine BMW” VDO TB? There are stories of the VDO branded parts being significantly lower quality despite being the same manufacturer.

Good question. I bought the VDO, both times from FCP (second time was free replacement), and they describe it as “OE” - their definition is that is “directly from BMW” and that it is the same part that “left the factory.” I do hope I just got a bad part the first time and that short lifespan isn’t a symptom of something else.


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[MSporting]

Update

12/2:
Before starting the car I,
- cleaned the TB
- did the adaptation reset procedure with the key in ignition
- lastly cleared error memory with INPA.

Car started okay and for the rest of the day would idle between 500 and 1k rpm but drove fine.

12/3:
Today idle returned to normal at 500. However the car felt sluggish on hard accelerations. Finally the SES light started blinking and appeared tonight.

Error memory showed:
- again the 140 tstat error
- new 50 and 62 error which corresponds to OBDII p1343 which is misfire in cylinder 1 with fuel cutoff.

I checked the tstat wiring and the dme. No signs of coolant.https://uploads.tapatalk-cdn.com/20191204/5f03dd3271887f063107a4212133e75c.jpghttps://uploads.tapatalk-cdn.com/20191204/5220e381996fe3879699cee85a00bbf9.jpg

Then I checked cyl. 1 plug which looked fine. And then swapped coil 1 and 2. Finished late tonight so I will start the car and check if the error follows the coil, tomorrow. https://uploads.tapatalk-cdn.com/20191204/d8e137b14b622ef5745705cb2cc03b34.jpg

Anyway, I just wanted to update you all on my progress. I'm still quite confused right now as to how it went from TB related errors to a misfire in cyl. 1. But we will see what happens tomorrow when I scan the car again.
The N62 tb I believe is "genuine bmw" vdo (has both logos).



Seems very strange for sure. I’m following your progress here pretty closely, as I mentioned I’m curious to see how other TB issues play out after mine. Thanks for continuing to give detailed updates.


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[Frankie]

b2ke:

The erratic and recurring nature of your problem sounds very much like a wiring fault somewhere in the TB harness. I recently went thru this exact situation but on the 6-cylinder M52TU in my 528iT.

This may help: Electronic Throttle Faults & Repair (http://www.frankies-bmw.com/5series/diy/throttle_faults/bmw_5series_throttle_faults.php).

[H3adBussa]

Update

12/2:
Before starting the car I,
- cleaned the TB
- did the adaptation reset procedure with the key in ignition
- lastly cleared error memory with INPA.

Car started okay and for the rest of the day would idle between 500 and 1k rpm but drove fine.

12/3:
Today idle returned to normal at 500. However the car felt sluggish on hard accelerations. Finally the SES light started blinking and appeared tonight.

Error memory showed:
- again the 140 tstat error
- new 50 and 62 error which corresponds to OBDII p1343 which is misfire in cylinder 1 with fuel cutoff.

I checked the tstat wiring and the dme. No signs of coolant.https://uploads.tapatalk-cdn.com/20191204/5f03dd3271887f063107a4212133e75c.jpghttps://uploads.tapatalk-cdn.com/20191204/5220e381996fe3879699cee85a00bbf9.jpg

Then I checked cyl. 1 plug which looked fine. And then swapped coil 1 and 2. Finished late tonight so I will start the car and check if the error follows the coil, tomorrow. https://uploads.tapatalk-cdn.com/20191204/d8e137b14b622ef5745705cb2cc03b34.jpg

Anyway, I just wanted to update you all on my progress. I'm still quite confused right now as to how it went from TB related errors to a misfire in cyl. 1. But we will see what happens tomorrow when I scan the car again.
The N62 tb I believe is "genuine bmw" vdo (has both logos).



Sent from my SM-N920T using TapatalkWell..... We know it's not coolant in the wiring or dme which is good. Since the tb wiring was spliced and the wires don't appear to be wrapped in anything, maybe the splices are the issue with the tb? Our engines get really hot and the heat cycling could have released a solder joint or something. A new wire loom is around $600-700, but you don't want to go that route unless necessary and I can't see the need for it just yet.

I know it sucks but I'd double check the tb wiring for breaks or loose connections.

As far as the misfire goes, that may lead you back to a breaking down wire loom unless the code follows the coil. Easy fix there. I've got several working coils, will send you one for the cost of shipping if you need.

When was the last time the thermostat was changed? It could just be bad.

Sorry if I've asked something you've already answered. I'm just throwing out ideas.

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[MotorMouth93]

Alright slow down guys, we know there's a cheap used TB in the car and we know it's been intermittently throwing errors. An M62 throttle body in it's death throes can definitely cause misfires, it happened on my car a month or two ago. First I got an engine failsafe which left me on the side of the road, I was able to get it running again and get home by pushing the throttle plate back and forth by hand a few times and it was fine for a couple days. Then I got in and started off to work one morning and the car started lurching with a flashing CEL from misfires. Promptly limped back home, tossed in my spare TB, and no misfires or failsafes since.

The thermostat code 140 means a problem with the electronic thermostat heater circuit and is likely an entirely separate issue.

[Chedley]

....
The thermostat code 140 means a problem with the electronic thermostat heater circuit and is likely an entirely separate issue.

Yep. You need to replace the thermostat. Use oem (Behr) tstat.
You cannot tinker with its electronic circuitry which is probably damaged with coolant corrosion.

[b2ke]

Update

12/12:
Error codes and engine failsafe message all came back.

Got refunded for the bmw+vdo N62 tb from eBay.

Ordered a new VDO N62 throttle body off FCPeuro. For those interested, the VDO tb has a vdo part n#. The bmw+vdo tb has that same vdo part # as well an OE bmw part #.

Thank you to everyone who helped me out and at the very least I now have INPA because of this thread.

P.S. I see a lot of different info on how to reset adaptations. This seemed to work for me, copied off https://www.rpmmotorsport.net/pages/bmw-throttle-body-adaptation-reset

(https://www.rpmmotorsport.net/pages/bmw-throttle-body-adaptation-reset)

1. Please make sure the ignition is Turned Off



2. Press the Gas Pedal to Full Throttle (while ignition is off).



3. Turn on the Ignition to the 3rd position for 30 seconds (Do Not Crank the Vehicle) (Do Not let go of the Throttle)



4. After 30 seconds are over, Turn Ignition Off and Remove Key (Do Not let go of the Throttle).



5. After Key is Removed, let go of the Throttle and wait 30 seconds.



6. After 30 Seconds, the Car can now be Started normally.

[JimLev]

I've never had to do the throttle adaption like that, and I've done it many times on a few cars...540tu engines.
1) Key to postion 2 for 30+ seconds, don't start it. You'll hear the throttle body open and close so the DME can learn it's open and close positions.
2) Turn key off, your done.
3) Start the engine.

[Chedley]

Exactly, that manual method works always.

But now that you have INPA set up and working, you can also use it to reset the adaptations: There is a box you click when you read the engine status I think. It erases the adaptations open/closed values; and next time you start the engine, it re-learns and sets the new values. Check it out, if you want to play with INPA.

[b2ke]

Update

12/17:

Engine failsafe came on a mile from my house. As I went to turn around back home the engine started sputtering and died. Tried restarting her but it would keep dying before I could get 5 feet.

Managed to drive and park in a public lot and walked home. Grabbed my laptop and biked back to the car.

Pulled error codes:
117 throttle potentiometer
119 throttle potentiometer 2 signal
62 multiple cylinder misfires
50 cylinder 1 misfire
57 cylinder 2 misfire.


What now? I'm going to leave the car parked in the lot for the time being and will go home and search for any related info. I'm tempted to call for a tow to a shop because this has been an ongoing issue since October.

[Chedley]

Back to basics : Check your battery and alternator.
A car that dies a mile from home could be a the sign of a failing alternator : the car runs on the battery for about a mile, then gives up, no more juice..!!

Could you post the INPA error reports for those codes ? INPA logs the voltage when the error occured...

[b2ke]

Back to basics : Check your battery and alternator.
A car that dies a mile from home could be a the sign of a failing alternator : the car runs on the battery for about a mile, then gives up, no more juice..!!

Could you post the INPA error reports for those codes ? INPA logs the voltage when the error occured...Test 9 in the cluster showed the battery voltage with car off to be 11.6V. And with car on the voltage jumped around from 13.3V up to 13.7V. (only idled for 30 secs while doing this test)

Now I'm getting misfire in cylinder 7 along with 2 and 1 mentioned previously.

It's idling rough so I'm going to keep her parked in the lot until later tonight and then I'll try to make it back home when there is no traffic. Or is this a bad idea? I have free towing with AAA, however, being only a mile away from my house I'd rather not go through the trouble.

Attached are the logs form reading error on INPA. Throttle body and misfire errors.




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[Chedley]

Replace the alternator.
Recharge the battery. Better yet, replace it also with a new fully charged battery.

[b2ke]

Replace the alternator.
Recharge the battery. Better yet, replace it also with a new fully charged battery.

Could you please elaborate on why this ongoing problem is due to my alternator? Based on what information/readings on INPA/test 9?

For INPA, which particular error memory log/reading points to an alternator problem? The language barrier is keeping me from fully understanding the logs on INPA.

For test 9, what should my voltages be? I can't seem to find concrete information on correct voltage readings with test 9. Information is scattered between readings with key in position 1 or 2, car off, idling, on load, etc.

Thank you :)

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[MotorMouth93]

Are these codes using the brand new TB or the EBay one still?

[b2ke]

Are these codes using the brand new TB or the EBay one still?Brand new TB.

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[MotorMouth93]

Did you do the manual throttle adaptations reset procedure?

[pleiades]

b2ke:

The erratic and recurring nature of your problem sounds very much like a wiring fault somewhere in the TB harness. I recently went thru this exact situation but on the 6-cylinder M52TU in my 528iT.

This may help: Electronic Throttle Faults & Repair (http://www.frankies-bmw.com/5series/diy/throttle_faults/bmw_5series_throttle_faults.php).

+1

[b2ke]

Did you do the manual throttle adaptations reset procedure?Yes. Upon installing the new TB on 12/12 the car would stall at a stop before I could make it off my street. Performed the key in throttle reset procedure and drove fine until today, 12/17. Todays symptoms are engine failsafe, previously mentioned errors (tb and misfires), sputtering and stalling.

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[Chedley]

Could you please elaborate on why this ongoing problem is due to my alternator? Based on what information/readings on INPA/test 9?
...


Alright..Forget INPA for now.

Your battery's voltage is 11.6 v, as measured by OBC Test#9, witgh engine off . And this after driving only a mile ??
Your battery is dead and not charging. It should read at least 12.5 volts, when fully charged.

I wonder whether all your TB problems are caused just by a bad/weak battery and a failing alternator.

As to how to check test the b attery and alternator, there are tons of info. Just google it.
Or check this one: https://www.bimmerfest.com/forums/showthread.php?p=6324298

[TheTailor]

If you get Google translate on your phone it has an option to use your camera to translate writing, saved my life during my time in the Netherlands.

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[mattmar1]

with a battery that low and the car only at idle the alternator voltage cant be tested reliably. assuming resting voltage is still reading 11.6 vdc (cluster voltage tests tend to show from .2 to .3 vdc lower than a reading at the battery), start the car, turn headlight hi beams on, A/C fan to full speed and rear window defroster on, rev the car to 2k rpm and read the voltage at the jump terminals or the battery terminals. (takes a helper of course) you should be seeing 13.8 - 14.2 vdc. your battery voltage makes something suspect, a fully charged battery is 12.6 vdc. either charging or the battery itself aint right here.

[Chedley]

My bet is on a bad battery that needs to be replaced with a new fully charged battery.
The alternator is probably ok as the battery-red-light is not turned on the dashboard.

[mattmar1]

i wouldnt bet on the cluster battery indicator as being a reliable indicator of an alternator issue. personal experience.

[1BlinkGone]

put a voltmeter on that battery with the engine running...if your alternator is doing its job, you should be seeing 13.5V or better. If not, your voltage regulator may need to be replaced, or the entire alternator rebuilt/replaced.

[b2ke]

Thanks for the responses I haven't had the chance to test the voltage with a meter. I will report back when I do so. Test 9 reads around 13.8v while I drive and 11.8v with key in pos 2. I believe it tends to show a lower reading than testing at the battery.

Anyway here's an update to clarify what happened on 12/17:

I drove a mile from home before the "engine failsafe" warning and SES light flashed. It was hard to pull into the parking lot because the RPMs kept dropping and the car would stall. There was no way I could make the mile trip home. I'm not entirely sure but to me that seems to be different than if the car had no power from the battery and died.

Anyway, prior to the tow truck arriving I performed the throttle reset. And to my surprise when I started her to drive off the truck bed there were no problems.

The SES light for multiple misfires have gone away on its own and I have been driving fine.

Agaib thanks for everyone's help, I will report back once I test with a multimeter.

The PO told me he replaced the battery in July when I bought the car though.

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[Chedley]

So, now that all is good now. yes ?

Do your car and yourself a favor:
Buy a battery charger/maintainer if you do not have one -it is only about $30 at HomeDepot-, and hook it up to your battery regularly to keep the battery fully charged. That will save you many headaches and a few tow calls .. ...

[b2ke]

So, now that all is good now. yes ?

Do your car and yourself a favor:
Buy a battery charger/maintainer if you do not have one -it is only about $30 at HomeDepot-, and hook it up to your battery regularly to keep the battery fully charged. That will save you many headaches and a few tow calls .. ...Yes, I can happily say all good right now and hopefully this will be the last time I need to update the thread on this topic.

I am still unsure why this problem has been sporadic. So based on 2 seperate posts indicating it could be a faulty wiring harness I went back and cut the wires I originally spliced for the N62 tb. I then resoldered the wires and sealed them with heat shrink.

I will definitely look into the battery maintainer as well. Thanks


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[capebmw]

This thread isn't over.......I will put money on it. Problems like this don't just disappear. I tend to think you have a voltage issue as well. Either a bad battery, a "failing" alternator. Personally I have had both of these without warning. These cars are very dependent on a constant supply of DC voltage and fluctuations in that will wreak havoc. BKE, wish you the best, but see you back here soon bud!

[mattmar1]

^^ agreed.your battery looks weak as well. yes the cluster voltage test does read .2 - .3 vdc lower than reading the voltage at the battery,12.0 - 12.1 vdc isnt a healthy battery reading, need to determine whether its a battery defect or a charging one.

[b2ke]

I am currently away from home but I will test the battery when I'm back.

Test 9 cluster had been reading 13.8v the past few times I've driven.

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[IcePlanter]

Problem solved! I know this is an old post but went through 14 levels of hell trying to get my 2002 530i M54 out of engine failsafe program and faults 70, 71 and 73 for throttle potentiometer sensor. The solution was a loose connection on the backside of the throttle. That was it. The throttle connection seemed tight but wasn't. You have to remove the intake boot and DISA to get to it but these are easy. I removed the connection cleaned both male and female ends with electronic connection cleaner including the outside of the connection to ensure it seated properly. And jammed the s out of it until it clicked into position. Reassembled the various parts. and CLEARED ALL THE CODES AND ADAPTATIONS before turning on the engine.

Before you go and replace your Vanos solenoids, MAF, random cables, chasing vacuum leaks. Give this a shot... I'd hate for my two weekends chasing gremlins not help someone else!

[Quanhell]

Hi I have the same problem without mistfire only errors about tb.my old oryginal tb BMW I change for new VDO TB and about 1k miles was great.now error come back.in Hiden menu I have voltage 14.6-15.2V in my opinion is too much and maybe second reason why something happens wrong is informations about open fuel tank when everything I'm sure is closed.any ideas?