Surfer2001

I've heard that jump starting these cars can mess with the PCM. I would not jump my car at all. PCM's go for 800 used.

Para82

First i've heard of this.

I've jumped my 997S battery twice, you will often see a PASM failure indicator after (mine did) and driving it for about 2 miles or 10 minutes typically clears all faults as others have experiences as well..

FearTheAardvark

Well shoot... I bought a new starter and attempted to replace it last night, but ran into the same symptoms. My brother decided to do a home brewed bench test on the starter we replaced, it's currently not working (based on the autozone test I had done today), but it doesn't really rule out whether or not it was working when I took it out.

I guess I'll repull the new starter I just installed and have it tested? I attempted Petza's proper jump and it still didn't work correctly, though I did it at the battery... Maybe the cable that goes from the battery to the starter is shady?

It's definitely approaching the call a tow truck, tow it 90 miles and pay out the nose stage.

FearTheAardvark

Oh!

The alternator I picked up also had 4 posts vs the one I pulled out that had three? I assume it's an optional ground, but I can't help but feel like the new alternator I got wasn't correct either...

http://www.oreillyauto.com/site/c/de...itemDetailTab_

Petza914

I'm not sure that O'Reilly, Advance, or Auto Zone is the best place to go for Porsche parts for your 997. Stick with the better, higher-end, proper distribution channels - Suncoast, Sunset, Pelican, Automotion, etc.

Did you try to rotate the starter by hand then do the bench test. Your starter might have a dead-spot on it - not that it means you'd be able to save the cost of a starter, but might be another data point in the troubleshooting as to the cause.

FearTheAardvark

The old starter is basically toast now, regardless of whether it was or not before my brother got to it. Arcing a set of jumper cables to it left it with continuity between the power and the switch signal (both posts) and the AutoZone test confirmed that the starter is 100% dead.

I definitely agree about the quality of the correct parts, what I wanted to determine first was if I was even troubleshooting the right part. It felt awkward buying something online basically on a guess for a thousand bucks with a challenging return process when I could pick it up locally for $150 and return it if it didn't work.

FearTheAardvark

Hopefully someone here's still interested and can help diagnose:

The starter works great, I've taken it out and had it tested at a local auto shop. So regardless of which starter is in, the noise is the same.

So I was thinking: if it works in the shop and doesn't work here, it sounds like a charge issue? I hooked up the leads of a volt meter to the starter. First to the "constant power" terminal. When my wife turned the key it went from 12.50 volts immediately to zero. I also tested the signal wire, it went from 0 volts to .05 (which seemed right to me). Keep in mind I had the battery tested, and it's 100%. Perhaps this is an issue with the wiring between the battery and the starter? This loss of voltage on turn-over also explains the flashing headlights.

Is it possible this is something far more dire like a seized engine?

Ahsai

What year is your 997? To check for engine seize, just try to turn the crank pulley with a ratchet by hand (clockwise only).

Do you have a positive jump start terminal in the engine bay? If you do, you can try to jump start from there to minimize the voltage loss on the long cables between the battery and the starter. You can use the engine bracket or the exhaust pipe as the ground point.

FearTheAardvark

2007, it's a C4S cab. I don't see any positive terminals in the back.

Ahsai

Yeah, looks like Porsche did away with that terminal in the engine bay in 2007 997.

I think it's worthwhile to check for seized engine first. If the engine can be rotated, it's likely a cable issue given what you have tried already. Btw, have you tried jump starting it using another car? If that doesn't work, it yet again points to cable or loose connection issue. To find out which segment of the cable is bad, you would need to perform some voltage drop tests on both the positive and negative cables.

earossi

Have you looked at the ignition switch? That could easily be your culprit.

earossi

Duplicate

Monster231

Did you have any luck bump starting the car? FWIW: The dealer I bought my car from put an auto zone starter in. I had the car shipped me, And it would not start to come out of the truck. They agreed to replace the starter. Long story short, After three failed AutoZone starters I forced him to put a Porsche Starter. Problem fixed!

FearTheAardvark

Update:

So I've had the car towed up to the dealership after determining this surpassed my ability to diagnose. There is actually two failures here, one appears to be the fairly common failure of the starter cable itself. $1400 fix

The other is more peculiar, it appears there's a contact pin in the power distribution box that's completely wrecked. While it would be nice to replace this part, it appears they don't sell it individually so we're looking at another $680 to replace the distribution box. Oh well, I'm happy it's not an engine.

FearTheAardvark

Sorry I seemed to miss this the last time around... That's good to know, I'll keep an eye out and certainly won't make the same mistake twice.