Porsche 997 Turbo - Engine stopped while highway tuning

[hbcmotorsport]

So you're right yellow is signifying double assignment. So i have a few things that are double assigned. I definitely did not change any pin assignments, and have just been running this how it shipped out of the box being a plug and play kit. I have double checked assignments with the Syvecs manual pinout. Crank sensor is assigned correctly to AN02. And cam is supposed to be AN05. I am leaning on the fact that the Cam (Inlet Variable Valve Timing) is not supposed to be assigned at all as i don't see it depicted in the manual. There are two other outputs for variable valve timing. (FUEL15:A24, and FUEL16:A25) which are correct.

Seems beyond strange, but could the ecu have reassigned pins while it was running? I doubt i could have fat fingered a shortcut that would have caused this...

The other odd thing that was happening just before all of this was the TACH needle sweeping to max and holding there, as well as what seemed to be a %25 TPS limit. Not sure what that's about, but at this point that is a secondary concern. Maybe something to do with a limp mode. Also, I have no intention of using the Cal switch out of the gate, but for some reason that is triple assigned. Again probably not related to the trigger issues, but just noting.

I will get a live view of the synclog after work today. Figured id start by confirming all the pin assignments are correct.

Thanks,

20231024_113131.jpg (278.94 KiB) Viewed 24041 times

[stevieturbo]

Crank is fine, not doubled up

Cam looks ok too seeing as it's used for main cam sensor and the VVT aspect. If the ecu was not happy with it, it would be reporting a problem in the messages in the bottom right.

I think it'd be red if it was a problem there. Haven't used the black screen in ages though, so colours will vary.

Fresh and valid cranking sync scope ?

I guess these engines use a chain, so not likely to have jumped teeth ? That would prevent sync'ing, although would not explain the engine not seeing the engine turning, or an rpm generated.

TPS limit will have related to the DBW fault you mentioned. But again, I did not see this on the log you posted. So it cannot be the correct log for these events you mention.
Likewise there is no limp mode active in the log you posted.

And no, there is no way the assignments will have changed themselves whilst driving. They all require manual device/programming which involves a brief engine kill for this to happen

[stevieturbo]

looking at this, I think your waveform for crank/cam look pretty reasonable. I haven't put any rulers on them, but they appear a pretty good match.

https://forums.pelicanparts.com/porsche ... 997-a.html

[stevieturbo]

try and get a fresh and definite up to date synclog. And in lieu of that, log AN02 and AN05 at 1000Hz when cranking and see what is picked up there.

Maybe it is as simple as the crank sensor has died.

You could also see if shorting the two wires together makes any difference when viewing ANO2 on a trace, or apply 5v to the signal wire from another sensor.
That would at least validate the wiring.

Although if you tested with a multimeter, you should get a small voltage reading between the two pins

[hbcmotorsport]

I tried looking at the synclog while cranking and nothing happens. I suspect since maybe the ecu isn't seeing the crank sensor it doesn't switch to "TURN" and therefore won't initiate a log.

When viewing the sensors directly I see the cam sensor (AN05), but not the crank (AN02). I will attach a link to a video I took.

https://drive.google.com/file/d/1cB28rJ ... p=drivesdk

Also I took a video of what I see on my synclog which looks to me to be the ecu possibly losing sync. Was this the same log that I sent over to you? Maybe I am not doing a good job saving the correct logs.

https://drive.google.com/file/d/1cF0Nss ... p=drivesdk

And when I click on syncError it shows the photo below. Maybe you're right, the crank sensor could have just randomly failed. Let me know if any of this intel gives you a clearer picture of what's going on. Appreciate your time and knowledge

https://drive.google.com/file/d/1cGer5o ... p=drivesdk

[stevieturbo]

Have you tried clicking either cranking or live , then cranking the engine to see what it picks up in a syncscope ?

As said, it's been years since I've actually tried it under such circumstances to do an actual live scope.

Normally mine always start, so it has automatically saved the most recent syncscope. Yours may have just saved from around when it failed ? As said before, the high voltages on the crank waveform right at the start, do not make sense for an engine at starter motor speed.

But yes, it may be the case if it does not see a crank signal at all, the scope may not start. But again, I've never tried this to see.

I do have a crank/cam simulator, but not with me here right now to try and test it on an ecu

But everything is pointing at it not seeing the crank turn.

So as said, verify the wiring. Is it OE wiring, or an aftermarket loom ? If wiring is good, can you pull the sensor out easily, or plug in another sensor and pass some ferrous metal object over it to see if you can detect a voltage change ?

[stevieturbo]

Seems that if you have the syncscope open.

Start cranking, and then click "live" and it takes a snapshot. ALthough a small snapshot.

The raw ANxxV inputs do show a functional trace though. My SIM is a square wave hall signal though,

Oddly, if I only give it either crank or cam, it will not register an rpm reading, although it does display "TURN".

Only with both crank and cam signals present does it then register an rpm reading, which I thought a bit odd. I'd have thought as long as it seen the crank turning, it would give an rpm reading.


Either way, same bottom line......you've lost your crank signal for some reason

[hbcmotorsport]

No matter what i do i cant get the syncscope to show live data. No matter if i click cranking or live. Nothing new is appearing in the log. I don't have any errors either. The syncstate remains in STOP and doesn't switch to TURN. Still seeing no feedback from AN02. I have checked the wiring and connector and all look fine. When i unplug the sensor and crank i get the exact same voltage reading of 4.961 constant, same as when its plugged in. I am going on the premise that the sensor has simply failed internally. The car is a 2007, original sensor.

I wish in knew what was going on with the syncscope and why i cant see anything there. Maybe a setting or something that is not set correctly. I doubt there is any issue with the ecu itself or im sure i would have other errors and malfunctions present.

It seems that all signs are pointing to a dead crank sensor at the moment. I will be picking up a new sensor tomorrow and see if that corrects it. Fingers crossed.

[stevieturbo]

As said before, either short the two sensor wires together and see what AN02V does on the trace, or apply 5v to the signal wire. DO NOT apply 5v to the sensor ground wire.

That will at least prove continuity of wiring to the ecu.

Sitting open circuit it will be close to 5v on AN02V.

If you short the two together, it will drop to around 2.5v on the trace. This will prove your wiring is intact, and of course that the ecu input is working too.
I've just done it sitting on a bench test here on an S8. That's with AN02 configured as bipolar as it would be for a VR sensor as your trace appears to be

[stevieturbo]

voltage high, nothing connected

voltage mid way, the two pints shorted together, AN02 to sensor ground. Then release again

an02 test.jpg (430.41 KiB) Viewed 24017 times