Slow crank rate when hot - 2006 911

bettergolf · #1

I’ve owned my 2006 911 Carrera S for about 10 years. Seems like when the car has been driven for over 10 miles, that if I turn off the ignition (maybe to fill gas tank), and try to restart the car, I get a slower crank rate? If the car cools down for a little, the crank rate goes back to normal.

#2

bettergolf wrote: ↑Tue Mar 28, 2023 3:36 pm I’ve owned my 2006 911 Carrera S for about 10 years. Seems like when the car has been driven for over 10 miles, that if I turn off the ignition (maybe to fill gas tank), and try to restart the car, I get a slower crank rate? If the car cools down for a little, the crank rate goes back to normal.

First, welcome to Carpokes! Please post early and often.

Re your car, it sounds like classic starter motor heat soak. It's not a problem unique to Porsches, but the 997 appears to be prone to it. As long as the battery is strong, then it's most likely the starter and starter cable. Age conspires against both, creating more and more electrical resistance. Heat adds to that resistance, especially inside a super hot starter, which makes it hard to crank, even for a healthy battery. If that's your issue, which would be my guess, replacing both the starter and the starter cable is probably wise.

a911 · #3

I'm curious if the car starts with the slower crank rate?? When I first read this what immediately came to mind was vapor lock, but if it starts, obviously that is not the issue.

bettergolf · #4

Yes, the car starts rather quick - even with the SLOW turnover rate.

a911 · #5

Well, I think Tom probably hit your problem right on the head.

Nicolae Ardelean · #6

I have a 2005 CarreraS with the same problem, we replaced the wire harness that is connected to the starter solenoid . This cable is got e Y split witch gets corroded in time and is heating up reducing the electricity to pass tru. This fixed my problem.

michaelmount123 · #7

Yep, common problem with the 997. I replaced both the cable and starter to avoid having to go back in there. Problem fixed.

aboyandhisdog · #8

Very interesting. I have an '06 997 and have had the same issue. I ordered a new Bosch starter today and am wondering if I also need the harness. Is this the harness that runs from the solenoid to both the battery and the alternator? My parts diagram is showing two different ones available:
1) harness;;PR:249 with: Connection point Alternator starter#99760701804 and,
2) harness;;PR:480 with: Connection point Alternator starter #99760701903

Any idea which is the one to go with or are there any differences at all??? Kind of a weird description the way they word things. If I'm going to dive in there, I might as well fix everything I can get my hands on!

Any input, much appreciated!

michaelmount123 · #9

I got my harness at Pelican Parts. Here's the part number:
997 607 019 03
Mine is a Carrera S. Put your car detail in PP website and it will give you correct cable.

aboyandhisdog · #10

Thanks, Michael! Just put in an order with PP.

BTW...the two different part #'s are: the 804 is for the automatic, and the 903 is for the manual. No idea why they would be different, but there you go...