Alternator charging problems when raining!

[fastboydave]

Folks......

I have searched in 996 and 996TT forums referencing "alternator" but havent found anything about this issue. Anyway.......this is a good one as it has the dealer stumped!!!

I have a 996TT (2001) and when i start the vehicle during or after it has been raining the alternator takes a number of seconds (approx 20 secs) to 'kick in'. The voltage on the dash reads around 11 volts (as you would expect) then after this time has elapsed you here a quick squeek and the voltages rises to the nominal value (approx 14V). This also happens when you poor water on the rear of the car (engine cover) and/or wash it.

Now, I know what your thinking, belt loose? However, as part of the service i have had a new belt and they have replaced the belt tensioners to try and sort this issue. Unfortunately it is still doing it.......

Any ideas??????

Cheers, Dave.

[Loren]

Based on the squeak - I would start with the belt.

[fastboydave]

Hi Loren.

There is no 'squeak' or apparent slipping up until that point and it is as if something gets 'loaded' at that moment and off we go.....

[PorscheFan]

Have you see any water into it when you pour water on the rear of the car?

I notice that water will come down to alternator area when you open the rear after washing the car. Most of the time, water will not touch the alternator. But, if a loose seal or other parts, maybe water will go directly into alternator or related wire. Check if your alternator is wet after you pouring water. Maybe you can find some clue.

[RFM]

Hi

Some alternators are carry out with a " freewheel pulley", check for correct working.

Regards

[eshuber]

Hi

My 02 996 with 34k does the same thing you are describing- except it takes only about 5 secs for the alternator to start charging after washing. So - I usually wash it on an incline to minimize the engine water intake or wait a couple of hours for the car to dry.

[fastboydave]

Couple of good tips there guys, thanks.

But lets face it, if the alternator does'nt work immediately when you start the engine when its wet, its a very poor show and something cant be right?? I will hasle the dealer to sort it as it should be covered by the extended warrantee. But at least now i have some more information behind me.......

Cheers, Dave.

[fastboydave]

Latest update on this issue.

Vehicle went into dealer and they have changed the Alternator under the extended warantee. Apparently they tested it by continuously puring water on the engine lid with a hosepipe etc. In any case, it rained hard here yesterday and it started charging immediately as soon as the engine started. Looks like its sorted..........superb!

[mtimmy]

Same thing for me ,. after a 3 days rain. i parked it on the street without moving it once during the 3 days.

started the car., voltage reads 0VOLT for around 10 seconds before it catch up to 10Volt then for another 10 second it goes up to 14V

Latest update on this issue.

Vehicle went into dealer and they have changed the Alternator under the extended warantee. Apparently they tested it by continuously puring water on the engine lid with a hosepipe etc. In any case, it rained hard here yesterday and it started charging immediately as soon as the engine started. Looks like its sorted..........superb!

[viper501]

Serpentine belt is either slipping due to moisture, tension, age, or a combination of the three. How long has it been since replacement, if ever?

[fastboydave]

Serpentine belt is either slipping due to moisture, tension, age, or a combination of the three. How long has it been since replacement, if ever?

Yeah, could be in mtimmy's case. In mine i had brand new belt (as part of service) and new tensioner (they thought that was the issue). I was never convinced and always suspected the alternator, 'shorting' out when damp/wet, as NO belt slippage was ever heard, which is very obvious when it does. Maybe he has ALL those issues??

[mtimmy]

Never heard the belt slip, but I am at 65k haven't get a chance to replace the belt yet.. will do it when I get time

Serpentine belt is either slipping due to moisture, tension, age, or a combination of the three. How long has it been since replacement, if ever?

Yeah, could be in mtimmy's case. In mine i had brand new belt (as part of service) and new tensioner (they thought that was the issue). I was never convinced and always suspected the alternator, 'shorting' out when damp/wet, as NO belt slippage was ever heard, which is very obvious when it does. Maybe he has ALL those issues??