Trouble shooting P0336 RPM circuit code

[Endurance Racer]

All,

I'm at a loss for my P0336 code.
Its a 2003 2.7L was a Tiptronics car converted to a manual (DME software for manual and appropriate wires swapped). It ran after the swap.
I have a p0336 code.

When I first got the code it happens with cam sensor bank 2 error. Replaced the cam sensor and that code went away but the crank /RPM error P0336 remains.

Per Porsche's diagnostics:
Check the crank sensor. Did that and tried a second one.
Check wiring from DME to sensor. Done, checks out.
Checked mechanical timing of all 4 cams to the crank. It all checks out.
Swapped DME (with immobilizer and transponder (key pill)). Still get the code.
I have RPM on the tach, in the scan tool and crank sensor output on an oscilloscope.

Any ideas?

[78F350]

It seems that you have been through the electronic possibilities and eliminated them. How about a bent tooth on the flywheel? A mechanical issue. You would still get the main tick from the timing gap, but a pulse from one or two teeth could be weak or missing.
My Audi info on that code also mentioned the possibility of reversing the polarity on the sensor, but a quick look at the engine in my garage says you'd have to break something to plug it in wrong.

..Please note the disclaimer in my signature before taking time to remove parts to check the flywheel.

[Endurance Racer]

Originally Posted by 78F350

It seems that you have been through the electronic possibilities and eliminated them. How about a bent tooth on the flywheel? A mechanical issue. You would still get the main tick from the timing gap, but a pulse from one or two teeth could be weak or missing.
My Audi info on that code also mentioned the possibility of reversing the polarity on the sensor, but a quick look at the engine in my garage says you'd have to break something to plug it in wrong.

..Please note the disclaimer in my signature before taking time to remove parts to check the flywheel.

I'm going to take a closer look at that for sure....

[Endurance Racer]

Looking again at the crank sensor oscilloscope trace, I'm seeing inconsistencies in the cyl #1 trigger.
Hum...

So i'm going to look at the sensor, sensor mounting, Flywheel teeth, flywheel mounting.

[Endurance Racer]

Problem found.
I need to pull the transmission to get to the flywheel to see exactly what happened.
:dance:

[JFP in PA]

Originally Posted by Endurance Racer

Problem found.
I need to pull the transmission to get to the flywheel to see exactly what happened.
:dance:

Pull your CPS sensor as well, normally if one is chewed up, so is the other one.

[Endurance Racer]

Originally Posted by JFP in PA

Pull your CPS sensor as well, normally if one is chewed up, so is the other one.

Yes I checked the crank sensor and it good. No marks No damage. It was something else.

[Gilles]

uhh, a new flywheel on the way?

[Endurance Racer]

Originally Posted by Gilles

uhh, a new flywheel on the way?

Yes, Since I have to get a new flywheel, does anyone have a recommendation for a nice light weight flywheel?

[pilot4fn]

Originally Posted by Endurance Racer

Yes, Since I have to get a new flywheel, does anyone have a recommendation for a nice light weight flywheel?

Aasco should be a good one. Mine is on a way, so no first hand experience yet.
If you install this, the clutch disc should have spings to take off some vibration and / or balance the rotating internals of the engine.
https://www.fvd.net/us-en/FVD11401202/lightweight-flywheel-986-9871-boxster-and-cayman-aasco-13-lbs-59-kg-aluminum.html

[Endurance Racer]

I'm reading that some don't think a lightweight low mass flywheel is a good idea because it leads to crank shaft failures.

[JFP in PA]

Originally Posted by Endurance Racer

I'm reading that some don't think a lightweight low mass flywheel is a good idea because it leads to crank shaft failures.

Next to which oil to use, this is always a contentious subject. Yes, there have been crankshaft failures associated with removing the harmonic dampening of the dual mass flywheel, Porsche released a TSB warning dealers to not warranty such damage if a single mass flywheel was in use.

One of the biggest issues is the lightweight flywheel itself, we have seen some that were several grams out of balance themselves right out of the box. That could be corrected by having whoever does your engine balancing spin it up and correct the imbalance (including the new clutch assembly), but not everyone does that, and ultimately pays the price.

Proceed at your own risk.

[seningen]

Originally Posted by JFP in PA

Next to which oil to use, this is always a contentious subject. Yes, there have been crankshaft failures associated with removing the harmonic dampening of the dual mass flywheel, Porsche released a TSB warning dealers to not warranty such damage if a single mass flywheel was in use.

One of the biggest issues is the lightweight flywheel itself, we have seen some that were several grams out of balance themselves right out of the box. That could be corrected by having whoever does your engine balancing spin it up and correct the imbalance (including the new clutch assembly), but not everyone does that, and ultimately pays the price.

Proceed at your own risk.

It's an endurance race car -- he won't know what killed it when it does die :-)

I have a SPB and a ChampCar with an AASCO.
Also had a Boxster S drive to the track car with an AASCO, about 10k track miles on that setup. Sold it a few years back -- still going strong as best I know.

YMMV,

Mike