[BMWAddict2007]

I have a 2007 328i coming up on 153k miles. On Friday I was leaving work to go home in the snowstorm we just had and my car died twice while waiting to get towed up the hill to my house. Was idling fine then all of a sudden rpm dropped really low and died. Started back up like normal then did it again about 5 minutes later but drove just fine after my neighbor pulled me up the hill. It sat till today as I wasn’t going anywhere in that snow (almost 14 inches).

Fast forward to today, car started right up and drove to work just fine. I go to leave tonight and once then car had been idling for about 3 minutes it died again, this time without the rev drop, just died all of a sudden. Started back up fine and I knew something was wrong but needed to get home. A few minutes into my drive the ABS, SES, tire, traction control, and brake lights came on (yellow). Along with this, rpm started to get weird. It would rev up quickly and as soon as I let off the gas, the rpms would drop really fast. (Car is an auto)

Something was also screeching very loud but I think that’s just a bearing or pulley that I can fix pretty easily once I locate which one it is.

If anyone has any similar experiences and could shed some light as to what these problems could be that would be much appreciated. I take pretty good care of my cars so it’s not like I’ve been pushing stuff off and it all finally went awry

Planning to try and pull codes later tonight, had to go back out as soon as I got home. In a different car of course

[gbalthrop]

Originally Posted by BMWAddict2007

... 2007 328i...On Friday... my car died twice...Fast forward to today, car started right up and drove to work just fine. I go to leave tonight and once then car had been idling for about 3 minutes it died again, this time without the rev drop, just died all of a sudden. Started back up fine and I knew something was wrong but needed to get home. A few minutes into my drive the ABS, SES, tire, traction control, and brake lights came on (yellow). Along with this, rpm started to get weird. It would rev up quickly and as soon as I let off the gas, the rpms would drop really fast. (Car is an auto) Something was also screeching very loud...

Depending upon what you use to read Fault Codes, my SWAG would be you might see:
P160C | 2DEB | Powermanagement Overvoltage

In addition to reading any Fault Codes saved in DME memory, I would recommend noting your current mileage (km) and then checking Freeze Frame Data for any code(s) saved in the DME, which would include the mileage/ km when the code was saved, and such things as RPM & possibly DME Voltage.

Also, you can drive in the neighborhood with "Hidden Menu" 9.00 activated, which will give you a display of Real Time system voltage on the instrument cluster as you drive. The system voltage with the engine running and alternator charging the battery should be in the range of 13.5V to 14.8V. "Overvoltage" or >15.0V can cause strange things to happen in the control modules, resulting in a "light show" on your instrument cluster as you describe.

If the "screeching" sound was consistent with a slipping belt, that would be consistent with higher than normal load on the alternator, making the alternator harder to turn & therefore a slipping belt.

You do NOT have to guess. Just open Hidden Menu 9.00 at startup, and drive around the neighborhood, periodically monitoring the system voltage. Here are instructions on how to set Hidden Menu 9.00, and you have to do that each time you start the car:
http://e90.wikifoundry.com/page/BC+hidden+menus

The good news is that a voltage regulator only costs ~ $40, and if you DIY, you can try that instead of spending ~$400 for a reman alternator.

Please let us know what you find,
George

[AllBlackBimmer]

Years ago my DSC module failed and caused my dash lights to come on - abs, traction, brake - and caused my car to stall out. My car was still under CPO warranty and the dsc module was replaced. Hasn’t happened since. I think this is a somewhat ‘common’ issue in our cars. Bmw even makes a ‘repair kit’ for it. Not saying this is def your problem, but I had similar faults/symptoms... might be worth checking into.
Good luck and report back.

[NGEE]

I'd listen to George. But that's happened to me twice - once was a bad battery, once was the fuse panel connector recall.

[robthewrench]

Take George's advice. You're having some sort of electrical voltage or amperage issue. Could be a failing alternator or something else.

[BMWAddict2007]

Originally Posted by gbalthrop

Depending upon what you use to read Fault Codes, my SWAG would be you might see:
P160C | 2DEB | Powermanagement Overvoltage

In addition to reading any Fault Codes saved in DME memory, I would recommend noting your current mileage (km) and then checking Freeze Frame Data for any code(s) saved in the DME, which would include the mileage/ km when the code was saved, and such things as RPM & possibly DME Voltage.

Also, you can drive in the neighborhood with "Hidden Menu" 9.00 activated, which will give you a display of Real Time system voltage on the instrument cluster as you drive. The system voltage with the engine running and alternator charging the battery should be in the range of 13.5V to 14.8V. "Overvoltage" or >15.0V can cause strange things to happen in the control modules, resulting in a "light show" on your instrument cluster as you describe.

If the "screeching" sound was consistent with a slipping belt, that would be consistent with higher than normal load on the alternator, making the alternator harder to turn & therefore a slipping belt.

You do NOT have to guess. Just open Hidden Menu 9.00 at startup, and drive around the neighborhood, periodically monitoring the system voltage. Here are instructions on how to set Hidden Menu 9.00, and you have to do that each time you start the car:
http://e90.wikifoundry.com/page/BC+hidden+menus

The good news is that a voltage regulator only costs ~ $40, and if you DIY, you can try that instead of spending ~$400 for a reman alternator.

Please let us know what you find,
George

Thanks for your advice. I pulled the system voltage up on the hidden computer and it read 14.3-14.8 while at idle. When moving or revved up slightly it dropped as low as 13.1.

I also discovered the OFHG is leaking so I’m wondering if that maybe leaked a bit of oil/coolant onto a belt or pulley and is causing the loud squealing noise.

I didn’t have time this morning to go through all the system and check for codes but here are some that I pulled: 2A94 crankshaft sensor, 5E19, 5E5B, 5DE1, 5DE0, and 5E1A

I have a buddy who said something about coil packs possibly being bad causing the rpms to do act crazy while driving. I also have had a slight flutter at idle for a few months now

[NGEE]

Originally Posted by BMWAddict2007

I have a buddy who said something about coil packs possibly being bad causing the rpms to do act crazy while driving.

Voltage seems within spec.

With the exception of the crank sensor code, those codes are DSC/Brake related, likely due to your instrument cluster lighting up like a christmas tree.

My experience is that a bad coil pack will send you into limp mode - not the christmas-tree instrument cluster you're experiencing.

Test your battery. Then make sure battery cable recall was completed.

Fix your OFHG, even tho not likely part of your problem.

Also, ABB may be right, tho I've had the DSC pump failure/replacement issue before, and did not cause sudden RPM fluctuations and/or stall.

[BMWAddict2007]

Originally Posted by NGEE

Voltage seems within spec.

With the exception of the crank sensor code, those codes are DSC/Brake related, likely due to your instrument cluster lighting up like a christmas tree.

My experience is that a bad coil pack will send you into limp mode - not the christmas-tree instrument cluster you're experiencing.

Test your battery. Then make sure battery cable recall was completed.

Fix your OFHG, even tho not likely part of your problem.

Also, ABB may be right, tho I've had the DSC pump failure/replacement issue before, and did not cause sudden RPM fluctuations and/or stall.

OFHG kit ordered and should be here by early next week hopefully. Only recalls open for my car are the blower motor and PCV valve ones from late 2017 I think it was? I just need to quit being lazy and call the dealer for those.

I didn't figure coil packs would cause that but figured I'd ask.

I plan to get the battery and alt tested tomorrow and go through all of the sections my code reader has to check for all the codes it has stored.

Thanks for all the info and I'll post tomorrow with any updates

[gbalthrop]

Originally Posted by BMWAddict2007

...I pulled the system voltage up on the hidden computer and it read 14.3-14.8 while at idle. [That's in normal range] When moving or revved up slightly it dropped as low as 13.1. [That's BELOW normal range, and that much fluctuation (13.1 to 14.8) suggests Voltage Regulator issue. Keep monitoring it however. You need to see what it reads DURING the "light show" (DSC/ABS/ etc. Icons on Instrument Cluster).]

I also discovered the OFHG is leaking so I’m wondering if that maybe leaked a bit of oil/coolant onto a belt or pulley and is causing the loud squealing noise. [Have you heard the squealing noise since the "light show"? Did the warning lights go away after shutdown & restart? Is there any oil on the alternator itself? Is your serpentine belt "walking" (moving front-to-rear) on the tensioner or idler pulleys?]

I didn’t have time this morning to go through all the system and check for codes but here are some that I pulled: 2A94 crankshaft sensor, 5E19, 5E5B, 5DE1, 5DE0, and 5E1A [I would suggest record ALL codes and FF Data (including mileage when codes saved), and then CLEAR all codes to see when they recur.]

I have a buddy who said something about coil packs possibly being bad causing the rpms to do act crazy while driving. [AFAIK the coils are "dumb" transformers with NO feedback to the DME, and if one or more had an issue, the DME would NOT change idle speed based upon coil function. "While driving" or "off idle" (Accelerator Pedal pressed) the Accelerator Pedal module sensor inputs to the DME are what regulate VVT Eccentric shaft position, controlling valve lift/throttle, so what is REALLY causing RPM fluctuation is erratic DME function. The DME, DSC and other modules may be erratic during "overvoltage episodes." Also, you would get one or more misfire codes which you do NOT have.] I also have had a slight flutter at idle for a few months now

AFAIK, unless there is an overvoltage code saved in the DME, the ONLY way I know to be certain what is causing the unusual events you described is to monitor system voltage DURING the event. Just try to pull over, shut down, and restart to prevent continued overvoltage operation which CAN damage electronics or even boil acid out of your battery.

I'm NOT guaranteeing you have an intermittent overvoltage issue, but that is the only thing I can think of that would cause ALL of the unusual events you describe. If I misunderstood, and the warning lights remained on after shutdown & restart, or if the screech continues with NO warning lights, please provide correct information.

George

[gbalthrop]

Originally Posted by BMWAddict2007

...I plan to get the battery and alt tested tomorrow and go through all of the sections my code reader has to check for all the codes it has stored.

Just to make sure you understand my theory of intermittent overvoltage. The battery is "currently" fine if it has enough voltage to start the car next morning. The alternator is charging in the normal range most of the time.

If it has been subjected to long-term overvoltage, you might find battery acid on & around the battery in the boot/cargo area, and that can quickly damage the battery well and "Transfer Points" in front of the battery, so I would suggest checking that.

Your vehicle's alternator output voltage is usually in normal range. However, in the scenario that others have described on this & other forums, the alternator on RARE occasion (which can become more frequent) puts out voltage >15.0V, sometimes in the range of 16V, or even 17V or higher. THAT overvoltage is what can cause multiple icons to appear on your dash due to Electronic Module "confusion." It can also cause many BOGUS errors to be saved in the modules whose icons flashed on the instrument cluster (DSC in your case).

The key is to read the Freeze Frame Data for ALL codes, to see the MILEAGE (km) when each was saved in the module memory, and also RECORD the mileage shown on your odometer when any warning lights appear, as well as continually monitor Hidden Menu 9.00 for system voltage. If multiple, apparently unrelated, fault codes appeared at the SAME mileage, and that mileage coincides with Alternator overvoltage, then replace the voltage regulator (~$40).

There may be certain clues in the "Electrical System Load" on the occasions when the car died, or the light show occurred. If ALL of those were occasions when you had the headlights on, heater blower on, radio on, etc. (high load situations), you might actually be able to "induce" a similar malfunction in the shop by basically turning many electrical consumers on (run/activate as many motors as possible, radiator fan, windows, etc.). Under those circumstances an idle speed increase of ~ 200 RPM would be normal, as the Power Management system is trying to prevent battery discharge, or offset the electrical consumption.

Please let us know what you find,

George

[Efthreeoh]

"A few minutes into my drive the ABS, SES, tire, traction control, and brake lights came on (yellow)" - These all match up to the codes "5E19, 5E5B, 5DE1, 5DE0, and 5E1A" based on the descriptions I checked on the internet (I didn't check against the Bentley manual).

The engine dying sounds like it is linked to the "2A94 crankshaft sensor" code you pulled.

You didn't say how old the battery is and if it is correctly spec'd to the car you have. If the battery is original, I'd look at it first. When the battery goes in the E90 all kinds of strange behavior occurs as the system tries to shut down non-essential electrical consumers.

[BMWAddict2007]

Originally Posted by Efthreeoh

"A few minutes into my drive the ABS, SES, tire, traction control, and brake lights came on (yellow)" - These all match up to the codes "5E19, 5E5B, 5DE1, 5DE0, and 5E1A" based on the descriptions I checked on the internet (I didn't check against the Bentley manual).

The engine dying sounds like it is linked to the "2A94 crankshaft sensor" code you pulled.

You didn't say how old the battery is and if it is correctly spec'd to the car you have. If the battery is original, I'd look at it first. When the battery goes in the E90 all kinds of strange behavior occurs as the system tries to shut down non-essential electrical consumers.

Battery is just over 3 years old and was coded to the car

[BMWAddict2007]

Originally Posted by gbalthrop

AFAIK, unless there is an overvoltage code saved in the DME, the ONLY way I know to be certain what is causing the unusual events you described is to monitor system voltage DURING the event. Just try to pull over, shut down, and restart to prevent continued overvoltage operation which CAN damage electronics or even boil acid out of your battery.

I'm NOT guaranteeing you have an intermittent overvoltage issue, but that is the only thing I can think of that would cause ALL of the unusual events you describe. If I misunderstood, and the warning lights remained on after shutdown & restart, or if the screech continues with NO warning lights, please provide correct information.

George

I took the car for a short drive yesterday, about 7 miles. The squealing is still there but nothing like it was at first. All the lights are gone and I couldn't replicate any of the symptoms I previously experienced. Although I don't really want to try to drive it too much with the OFHG leaking like it is. Checked the coolant and it was pretty low. I always keep BMW spec coolant in my car but don't want to fill it just to dump it right back out changing the OFHG, which will hopefully happen next weekend

Also, can you expand on what may cause overvoltage so I might know what to look for? I've never heard of this issue before

[vilord]

To me, this sounds like the alternator wasn't spinning due to oil on the belt.
I'd suggest replacing the belt when you replace the OFHG, as the oil can cause the rubber in the belt to deteriorate.
The dash will light up like a christmas tree if the voltage drops too much due to the alternator not charging things.

I would start with the simple things before going too deep into diagnosis. The time you've spent pulling codes, you would be half way to a new OFHG.

[gbalthrop]

Originally Posted by BMWAddict2007

I took the car for a short drive yesterday, about 7 miles. The squealing is still there but nothing like it was at first. All the lights are gone and I couldn't replicate any of the symptoms I previously experienced...
Also, can you expand on what may cause overvoltage so I might know what to look for? I've never heard of this issue before

In your case as I now understand it, you have (1) oil leak from OFHG & (2) squeaking from unidentified source, though NOT as loud as when dash warning icons were lit. I would address those two issues FIRST, or at least while you monitor system voltage for any transient spikes. If there is belt squeak (or Crankshaft Damper Squeak -- see below), the source/cause of that needs to be identified ASAP, as belt failure CAN cause engine damage if the belt gets wedged between Crank Damper & crankshaft front seal with belt shreds getting sucked into the crankcase.

I'm NOT an electronics expert, and my basic understanding of electricity is just concepts derived from "analogs" or comparisons of things we CANNOT see (electrons) with those we CAN see (water flow).

A simple analogy for what the battery & alternator are doing during engine operation is to think of a thermos with a pour valve, like the one shown in this ad:
https://www.amazon.com/Igloo-Beverag...ds=thermos+jug

In the following Analog, "=" simply means "analagous to" and NOT mathematically equal to.
The battery is the jug, and the "electrical consumers" (starter motor, headlights, blower motor, radiator fan, radio, etc.) are the push valve which may vary the amount of "load" or draw/ drain on the battery (how much water flowing OUT of the jug). The alternator is a "pump" which is trying to provide enough water flow (= current/ Amps) to the jug to keep the water level in the Jug near the top.

IF the water level (= pressure = battery voltage) in the jug was LOW when the valve was pushed (= motor started & consumers activated) the alternator must not only keep the level where it was on startup, but increase that level to obtain proper battery voltage. The largest "electrical consumer" in terms of Amp draw is the starter motor, and the alternator works hardest (requires the most power/ effort to turn the alternator) immediately after startup, when it is replenishing starter draw.

On forums related to 80's & 90's model Jaguars, there were FREQUENT reports of crankshaft damper failure, where the rubber bond between the inner cylinder of the damper and the outer pulley assembly that drove the belts (which included the alternator drive belt). The common denominator for such failures was a loud Screech (similar to a belt slipping) which occurred for several seconds immediately following startup, during this period of the alternator attempting to replenish starter draw.

I have not heard of any confirmed cases of crankshaft damper failures on E9x models. That may be a matter of age (oldest models 13 years-old), OR it may be design/ rubber bonding improvements in the 90s and early 2000s.

The function of the Voltage Regulator (which is controlled by the DME via the BSD bus, related to the IBS measurement of battery Voltage & Draw), is to control water level (= pressure/ Voltage) in the Jug = battery, by controlling water pressure (= alternator output voltage) to the Jug. ONE of the failure modes of the Voltage Regulator is to cause the alternator output voltage to be TOO HIGH (overvoltage). Since I do NOT profess to understand HOW the voltage regulator is supposed to work, I cannot explain that faillure mode in either electronic terms, or in any proper ANALOG. All I can do is suggest tests that I would do if your vehicle's symptoms occurred on MY vehicle. Since I am a DIY type, if I had a confirmed case of Hidden Menu 9.00 showing >15.0V on occasions when otherwise unexplained warning lights appeared momentarily on the dash, and if related fault codes ONLY were saved at mileage/km when system voltage > 15.0V, I would take an hour or two to replace my Voltage Regulator per this link:
https://www.newtis.info/tisv2/a/en/e...roller/HwWK2Fi

I have seen at least 5 reported instances on this forum & Bimmerfest of random warning light illumination on the instrument panel ("light show"), accompanied by "overvoltage" (system voltage > 15.0V) which were remedied by replacement of the $40 voltage regulator OR by the owner having the entire alternator (INCLUDING the voltage regulator) replaced at a part cost of $400+, NOT counting the labor.

I personally would NOT do either one until I confirmed system voltage >15.0V accompanied by "light show" and/or engine shutdown. I would make (1) OFHG replacement, (2) careful examination of serpentine belt, tensioner & idler, and (3) identification of squeal source the top priorities.

George

[BMWAddict2007]

Originally Posted by vilord

To me, this sounds like the alternator wasn't spinning due to oil on the belt.
I'd suggest replacing the belt when you replace the OFHG, as the oil can cause the rubber in the belt to deteriorate.
The dash will light up like a christmas tree if the voltage drops too much due to the alternator not charging things.

I would start with the simple things before going too deep into diagnosis. The time you've spent pulling codes, you would be half way to a new OFHG.

Alternator is bad and was making a ton of noise when I took it out and spun it around. All the tensioners and pulleys are good which isn’t surprising as I replaced them about this time last year.

I only spent about 10 minutes pulling codes before work yesterday so not like I wasted a ton of time imo. Plus I don’t have the parts to fix it yet, still waiting on it to show up.

[BMWAddict2007]

Originally Posted by gbalthrop

In your case as I now understand it, you have (1) oil leak from OFHG & (2) squeaking from unidentified source, though NOT as loud as when dash warning icons were lit. I would address those two issues FIRST, or at least while you monitor system voltage for any transient spikes. If there is belt squeak (or Crankshaft Damper Squeak -- see below), the source/cause of that needs to be identified ASAP, as belt failure CAN cause engine damage if the belt gets wedged between Crank Damper & crankshaft front seal with belt shreds getting sucked into the crankcase.

I'm NOT an electronics expert, and my basic understanding of electricity is just concepts derived from "analogs" or comparisons of things we CANNOT see (electrons) with those we CAN see (water flow).

A simple analogy for what the battery & alternator are doing during engine operation is to think of a thermos with a pour valve, like the one shown in this ad:
https://www.amazon.com/Igloo-Beverag...ds=thermos+jug

In the following Analog, "=" simply means "analagous to" and NOT mathematically equal to.
The battery is the jug, and the "electrical consumers" (starter motor, headlights, blower motor, radiator fan, radio, etc.) are the push valve which may vary the amount of "load" or draw/ drain on the battery (how much water flowing OUT of the jug). The alternator is a "pump" which is trying to provide enough water flow (= current/ Amps) to the jug to keep the water level in the Jug near the top.

IF the water level (= pressure = battery voltage) in the jug was LOW when the valve was pushed (= motor started & consumers activated) the alternator must not only keep the level where it was on startup, but increase that level to obtain proper battery voltage. The largest "electrical consumer" in terms of Amp draw is the starter motor, and the alternator works hardest (requires the most power/ effort to turn the alternator) immediately after startup, when it is replenishing starter draw.

On forums related to 80's & 90's model Jaguars, there were FREQUENT reports of crankshaft damper failure, where the rubber bond between the inner cylinder of the damper and the outer pulley assembly that drove the belts (which included the alternator drive belt). The common denominator for such failures was a loud Screech (similar to a belt slipping) which occurred for several seconds immediately following startup, during this period of the alternator attempting to replenish starter draw.

I have not heard of any confirmed cases of crankshaft damper failures on E9x models. That may be a matter of age (oldest models 13 years-old), OR it may be design/ rubber bonding improvements in the 90s and early 2000s.

The function of the Voltage Regulator (which is controlled by the DME via the BSD bus, related to the IBS measurement of battery Voltage & Draw), is to control water level (= pressure/ Voltage) in the Jug = battery, by controlling water pressure (= alternator output voltage) to the Jug. ONE of the failure modes of the Voltage Regulator is to cause the alternator output voltage to be TOO HIGH (overvoltage). Since I do NOT profess to understand HOW the voltage regulator is supposed to work, I cannot explain that faillure mode in either electronic terms, or in any proper ANALOG. All I can do is suggest tests that I would do if your vehicle's symptoms occurred on MY vehicle. Since I am a DIY type, if I had a confirmed case of Hidden Menu 9.00 showing >15.0V on occasions when otherwise unexplained warning lights appeared momentarily on the dash, and if related fault codes ONLY were saved at mileage/km when system voltage > 15.0V, I would take an hour or two to replace my Voltage Regulator per this link:
https://www.newtis.info/tisv2/a/en/e...roller/HwWK2Fi

I have seen at least 5 reported instances on this forum & Bimmerfest of random warning light illumination on the instrument panel ("light show"), accompanied by "overvoltage" (system voltage > 15.0V) which were remedied by replacement of the $40 voltage regulator OR by the owner having the entire alternator (INCLUDING the voltage regulator) replaced at a part cost of $400+, NOT counting the labor.

I personally would NOT do either one until I confirmed system voltage >15.0V accompanied by "light show" and/or engine shutdown. I would make (1) OFHG replacement, (2) careful examination of serpentine belt, tensioner & idler, and (3) identification of squeal source the top priorities.

George

Thank you for the detailed info on that.

I believe the alternator is bad and needs replacing and I’m almost positive that’s the source of my noise as all belts look good and the pulleys/tensioners are good.