Scotttmac

So last August I purchased my first Porsche, a 2002 Cab with 59K on it. I had it freshly serviced to include new belt, WP, and upgraded IMS among a number of lesser items. It’s been a great car and I’ve been loving it for the last 4K miles I’ve put on myself.

Today when taking it out, I’m experiencing a loss of power when I hit 4,500 rpm. Can’t get any higher. This seems to be happening in all gears. At lower rpm it seems fine. No strange noises, smells, or leaks. No misfires. No lights on dash. I’m left scratching my head.

I’m most likely taking it to my mechanic tomorrow. My big questions are (1) has anyone experienced a similar issue and (2) do you think it’s ok to drive to him or should I have it trailered?

Thanks in advance.

Mike Murphy

Could be clogged air filter or bad mass airflow sensor. Any codes?

dak911

I would trailer it...no clue as to the cause...(If you have AAA, use that or, your auto insurance probably has towing)

Ratchet1025

Very sorry this is happening, hope it is some thing simple (sensor, etc.). Please keep the thread up to date with the info.

pdxmotorhead

Don't panic,, wait till you have the mechanic check it out.. Don't drive it till you check it..
Tow is the cheapest part of the adventure..

Scotttmac

An update:

Spoke to the mechanic. There are no lights, faults, or codes showing. Did some investigating, found no obvious issues.

Air filter is clean and pristine.

During the investigation yesterday, the engine could rev to 5k just fine when not in gear.

When attempting to replicate the power loss today, and hopefully get a code or light to throw, the issue is gone.This has us leaning towards a failing MAF. As far as anyone knows it’s original to the car and has never been cleaned.

More info as it comes...

Byprodriver

Could be the fuel pump, they die slowly & a lot of them are aging out.

Mike Murphy

I was thinking the same thing.

Paul Waterloo

Another thing it could be is a failing catalytic converter. Once the honeycomb starts breaking down, it clogs the air flow path and it works correctly at low load (low airflow) but cannot breath at high load (high airflow). I've seen it many times on other cars, but I have never heard it reported here.

Mike Murphy

I didn’t think of this, but you are 100% correct that it could cause this problem.

5CHN3LL

A clogged catalytic converter seems unlikely to present as an intermittent issue.

I'm gonna go with one or more cracked coil packs.

The only intermittent down-on-power issue I've experienced with either M96-powered car I've owned (other than short-term timing retardation courtesy of PSM) was caused by failing coil packs.

Scotttmac

So after determining it was not the MAF, and that the issue was intermittent with no indicators as to when or why it would happen, I kept driving until finally the CEL came on and a code was thrown - P0335 for crankshaft position sensor.

After this, the problem started to present when the car was fully up to temp after extended driving.

Replaced crank position sensor and all is right with the car again.

cds72911

Great news. Thanks for the update. I like it when they turn out like this.

David993S

Good news. Glad you can enjoy it again. They're great cars that sometimes require attention.

hatchetf15

OP,
Thank you for the update. The resolution of your issue adds more to this forum’s diagnostic data. So now CPS can be added to our troubleshooting checklist.