Where is the voltage regulator on panny turbo?
What do they call it in fsm?
They call the alternator, the generator.

Was driving home today, car got check engine light. Had diag tool with me.
Parked, scanned. Multiple misfires.
Cleared but could not start car. Thought no juice. Attemptes few times to start few seconds apart. Last time tried, power just died when I turned key, and sometime later plastic smell coming out of car.
Voltage on cluster said 11 volts or so. Not even clicking.
Used autozone battery to boost. Boosted ok, but autozone guy said as soon as boosted, he saw very faint grayish smoke in area of driver side by shock where wires and boost poles are. Said very small and disappeared.
No errors anymore on car.
But got home, used multimeter directly on battery terminals. Observed:
- car off fully...cluster read 12.5v...multimeter read 18.2v
- car ignition on...cluster 12.6v...multimeter read 18.5v
- car started...cluster 12.6v...multimeter read 18.6v
Worried about the alte rf nator or voltage regulator going bad.
Need to find regulator to see if grounded ok.
Car vatt should not be higher than 14.5v.

Need help appreciate any given. Thanks.

 

My guess is a bad ground from the engine to the body. So I agree you’re on the right track. Had a similar experience on another car where the body grounds were used to carry high current because one of the major ground wires was corroded. The insulation on the body ground burned through because they were basically behaved like toaster wire from the high current. Check all ground connections!

 

Do you have advice on PD? Never really did pd on electrical and not familiar with ground locations on PTT. If you can help with info will be great. Thank you in advance.

So far,

1. disconnected batt from car (terminal wires). Checked voltage on batt with dmm. Shows 17.4 volts, should be about 14.5 or so. Does this mean battery is bad because of this event?
Car starts and runs ok as is, but I dont want to run it because the 18v charge surely wont be good for multiple 12V systems in the car. am I right or is is safe to drive.

2. Just ordered oil pressure sensor to swap out (had the oil pressure fault error pop out, not 3rd time in a couple months). Will swap that out - unrelated to the electrical thing as far as I know.

3. When I had batt connected to car, with car off but acc on, batt voltage (across its terminals), was about 18.1v. When car started running, voltage across terminals showed 18.5v. The cluster batt voltage continually showed 12.6v or so.
So which is correct? Why am I seeing 18 on batt while cluster volt shows 12.6V.

4. Got the issues initially due to cylinder misfires.
Replaced plugs in affected cylinder (7).
Next day got similar but for cyl 5, 6.
Replaced 5, 6 with new plugs (now total 3 swapped - 5, 6, 7).
Next day, driving home, get cylinder misfires. Park in lot near autozone. Scan codes, cyl 5, 6 misfires.
Cleared all codes from car.
Try start car, now get error oil pressure fault, no oil pressure on cluster.
Shut off car, repeat again with same error. On third time, car starts and oil pressure appears on cluster and shows ok at about 1.2bar.
Turned off car, scanned codes, none, cleared anyway.
Now, car wont start (batt on cluster shows 11.1 v). Try turning over maybe 5 times.
On last try, try turn key, power appears to die (cluster goes blank, no turn over). So I think batt bad.
Disconnect, reconnect batt in trunk. Nothing.
Smelled insulation burn smell from engine (under hood, near driver side shock area).
Went to autozone. Got sales guy get batt from store, with boost cables.
Go to car, connect new batt to boost terminals in car. I go into cabin to turn key, while sales guy looking at hood.
I turn key, car starts, sales guy said he saw a small puff of grayish smoke in area of front driver shock mount where there are many wires. Smell was there for short time but disappeared.
Batt volt on cluster was saying 12.4v or similar.
Car now is running fine. I drove home about 15 miles. No issues or errors.
Connected multimeter to battery in trunk. With car off but acc on, Shows 18.1V. Expected 14.5V. Cluster shows about 12.5V
Started car, batt shows across terminals 18.5V. Cluster shows 12.6V
Stopped car, no more insulation smell.
Disconnected batt from car, checked voltage across terminals. Shows 18.4V. wow, should not be this high I am thinking.
Left disconnected overnight. Now checked voltage across batt. shows 17.5v. still too high.
So now, car in garage battery disconnected. Oil pressure sensor ordered on way.
Need to get a good idea on how to pd the grounds, and check where voltage regulator is on this car to see if bad.
Anyone who can help thank you very much in advancd.

 

I only see one grounds strap running from the Body to just under the Generator - it actually might be connected to the generator but I can't see from above.

 

Double check the range / DC vs AC on your volt meter.

It's tough to get 18V out of a 12 V battery like you are reading.

Somethings not right. At this point your panel gauges are giving readings that seem to make more sense.

Keep us informed ---

 

UPDATE:

I took the battery itself to an auto parts store Oreillys. They put a load tester on it. Comes out as good.
Asked them what the voltage read. They tested again and showed me - 12.59V. WTF.
So I go home. Originally used a small 20 dollar DMM. Took out my good 400 bucks DMM.
Measure voltage across batt terminals. Reads 12.6V.
So the voltage on my batt is good, the batt is good too. The cheap DMM is just POS. It was ranged to 20V so that was set right.
So I have a good battery, with good voltage. Does this mean the alternator should be ok? Starting to think it is.
When I start car, idles smoothly no issues, had to drive it into different garage where all my tools are, and had no issues at all. All seemed to work fine.

I am at a loss now. I wont drive car until the oil sensor comes and I get a chance to crawl under car.
Appears that the cluster was showing correct voltage. No new errors were detected last time I scanned for them, today am.

 

Start by tracing the battery ground cable. It will be bolted to the engine somewhere, but I’m not sure where. May have to remove the underbody panel for a better visual. I would remove that connection and clean it. Will be obvious if there is a corrosion issue. A bad engine ground could cause current backfeed through other electrical components when starting and cause them to fail.


If your multimeter is showing 18 volts across the battery when both cables are disconnected, there is a problem with your meter, not the battery. It cannot produce more than 13 volts.

 

Thanks. Already determined one of my multimeters is POS. Took batt to shop who load tested it. Showed me voltage 12.59V.
At home brought out my good expensive dmm, showed 12.6V, so small meter was POS. Batt determined good, with good voltage.

 

I had a voltage regulator fail on an Audi S8 and it was incorporated into the alternator (generator) - fortunately my mechanic friend had an A4 alternator in his parts bin and he was able to pull the voltage regulator from it and install it into the S8. I wonder if Porsche does the same thing?

This car had 180k miles on it at the time so no real surprise that it failed. How many miles on your car? Hoping it's just a ground/corrosion issue that can be easily remedied. You're on the right path IMO and you'll get this sorted out.

 

So far, took apart the GND and PWR terminals under hood. Cleaned well to have good contacts. Put back together. Cleaned the batt terminals and connections well in trunk.
Waiting for oil pressure sensor to arrive. Then I will put car up, replace sensor and get a good look at the GND strap from alternator to engine. Also planning to use snake camera to trace the power cable under hood, where it disappears from jumper terminal, into the side fender hole. Hoping to see something that can cause my symptoms, but doubtful since if the PWR wire was shorted to chassis, I would be burning fuses left and right, and if not, then would have a nice warm light show.

So far, after last car reset, no issues, no codes, no nothing. Drove it about 60 miles so far, in normal mode, sport mode and sport plus mode. Even did a launch to try cause something to surface. Nothing. No errors, etc.
Last thing I did today before going to work, curiously, was disable reversing camera in PCM. Why? Well, over last month or so, it sometimes quit working, and interestingly, only if you read codes, you can see PCM code for reverse camera, saying open circuit. My assumption is camera may be going. Need to find way to get to the camera to remove, and inspect or replace. Anyone knowing how to do this will be awesome. FSM does not have good info (unless I am not looking in correct place).
Thanks.

 

Looking at the wring diagrams I have, the alternator field control (voltage regulator replacement) is provided by the DME control unit. There is not a separate device for alternator control.

Also, if you look in the FSM, there are pages in the back that detail the location of all the ground attachment points (there is a description of location). This might be a help to you in troubleshooting.

 

I think I figured it all out.
2 separate issues here
- ignition coil(s) going bad
- oil pressur sensor intermittent (twice now in a month) not reading

Once coil needs replacing. Possibly up to 3. Replaced all my plugs and coils 1.5 years ago (28k miles). Ordered ZSE042 rev 14, but after they arrived, revision received was 06.
Only one of the coils was ZSE042 latest revision. Was really surprised to see coil go bad after only 28k miles. Old rev can help explain it.
There are 2 other coils that I removed and cleaned, that are running ok now, but have seen misfire on them. Plugs were already replaced regardless.
So on the coil, so far so good. Mad cannot drive my car though (well, can if I reset the codes each time, but they do come back every 60 miles or so).

Oil pressure sensor will be swapped asap. Should be easy, and I do not want to run chance of this not working right.

As to the electrical, I had a dealer look at the car about 2 weeks ago. It was a routine 'hey can you scan and tell me buddy what you think needs doing'. They said sure.
The genius who 'looked' at it, left a rubber tube of some sort, inside bay. Does not belong to car. After couple weeks being there, the tube moved and just happened to relocate to where it was touching the manifold. Hence the smell. Was strict coincidence for all these 3 things to come together. At least I have resolution to this. Still, have to wait for the coil, which is a bummer.

Will update again after swaps. Thanks so much to all who helped. You ever heard of 28k coils needing replace? wow, talk about short lived.