986 S problem at idle, engine won't rev and shakes, battery disconnected

[Gorthaur]

Hi guys,

I’m writing from Italy, owner of a 2000 986 S, 84.000 km on the clock.

First of all, I have to apologize for my poor English.

Recently I had my cluster bulbs replaced thanks to the good DIY guides found over here, so, thank you so much for helping us all with your knowledge and patience.

In order to do the job, since my car features the optional alarm, I previously disconnected the negative cable of the battery while leaving the ignition key on position 2 as read on the board in order to avoid the siren to scream (is this correct, BTW?).

With the cluster back in place, without touching the key nor the gas pedal, I connected the negative cable and found everything was fine, then I waited for a few minutes with the key still in position 2 thus letting the e-pedal to reset itself, and eventually removed the key and left the place.

Two days later I picked the car up but the engine was really strange at idle. No fault lights on the cluster but no power at all, it hardly reached 1600 – 1900 RPM with the aircon switched off even if I floored the pedal.

The whole car shaked violently but the engine didn’t stall. If I pushed on the gas pedal, it revved a little making a smoother noise and behaving normal, but just up to 1600 – 1900 RPM. It seemed there was something at work avoiding the engine to rev.

Tried several times to do the 1-minute procedure, tried to fire it up and swich it off a million times, then called the local PD but received nothing but a “shame on you for having disconnected the battery”.

Called an indi whose suggestion was to blindly replace the MAF (...even though the problem was showing itself at idling and not over 4000 RPM).

Eventually phoned another indi; this nice chap came, attached a small diagnostic device to my car and told me there were no error codes displayed. After half an hour the engine got warm and everything was perfectly normal, so he invited me to drive the car for some thirty minutes and so I did.

Problem is, though, yesterday the issue came back again and didn’t go away even after a million 1-minute procedures, dozens of key-on-0-to-key-on-2.

I haven’t got access to a Durametric.

When I set the key on position 2 I hear a very low “buzz” which goes on forever, until I fire the engine.

I’ve got a GPS from my Insurance Company on the positive pole which I cannot remove.

What do you suggest? I’m really struggling… Shall I disconnect the negative cable and leave it aside for a few days, as read over here? What must I do when disconnecting the battery in order to avoid the alarm to wake everybody up?

Thank you in advance for your help, I really need it!

Cheers,

G.

P.S. If you reckon it would help, I can record the engine noise and attach a file...