kilodawg

Can all this really be happening???? I am now officially freaking out.

A week ago I posted that I had just backed my 993 out of the garage washed and detailed it and when ready to return it to the garage it wouldn't start. Nothing except the interior lights, fan and radio which all behaved normally but no other clicking sound at all.

I'd feared that I had an issue with the immobilizer since over the past month or so I'd encountered a spurious flashing of the immobilizer lamp while driving every now and them. In each case shutting the car off reset it but I was worried that this time it had hard failed.

Anyway, I went on the forums and found that a bad battery will behave exactly the same way so I took my battery out had it charged and the car started right up. However, when I started it a second time nothing. So I went and purchased a new battery and sure enough the car started right up and did so several times over the next week though I didn't drive it much.

So fast forward to today. I get in the car and drive to work. The car starts fine but on my drive to work the immobilizer light starts flashing again. This time it periodically clears and then restarts flashing. I figure it's just up to it's old tricks but today when trying to leave work the car won't start again. Symptoms are just like the first time a week or so ago. So I wonder if perhaps something had drained the battery and that was my problem all along. However, I tried both to jump the car with a power pack charger and I also even replaced the battery with another new one and still no joy with the same symptom as before dash lights and radio but nothing else.

I have now defaulted to thinking that it was the immobilizer all along and all the nonsense with the battery was just a red herring.

Now here comes the kicker..... In doing a bit of research this evening, a new immobilzer runs anywhere from $1000 to $1500 but wait for it.....They are on a 1 to 2 month back order from Germany!!!!!! Did I mention that my 993 is my daily driver?

Does anybody see a happier ending to this scenario?????

AOW162435

Ralph,
Have you ever replaced the $10 ground strap from the battery to the body? I replaced mine 5 years ago after reading enough comments that these go bad at the crimped ends (within the crimp).

That and the DME relay seem to be cheap insurance with our cars.


Andreas

NC TRACKRAT

I also recommend bypassing the clutch microswitch. With the IMMOBILIZER light flashing while you're driving, that may not be the problem in this instance but at least it'll be one less thing to worry about.
p.s.: Oh, a TIP, Then, you're going to have a hard time finding the clutch microswitch!

kilodawg

A couple of other things. First it's a tip and second I do note that when I try and start the car pressing the fob does clear the immobilizer light in the clock. Would that still happen with a failed immobilizer I wonder?

techman1

Any other flashing dash lights or other symptoms?
Sure sounds like the battery change has something to do with it. Since later the battery swap trrick did not help, I feel the cables are suspect.

Replace the ground cable.

kilodawg

No other light symptoms. All those indications are normal. If there wouldn't have been the flashing immobilizer indicator on the clock today while driving cables and starter would be at the top of my list.

I do know that the plastic housing that covers the positive cable run under the spare on the trunk floor has cracked loose and I'm not sure of the condition of the cable underneath but other than that the trunk was very clean.

pinlius

I had very similar symptoms with my '97. Also had the radio cut out periodically. After doing my research here I replaced the perfectly good looking ground strap about 6 months ago. I haven't had any problems since then!

911Dave

A new battery ground strap is very cheap, so you can try that, but an intermittent immobilizer function when all other car functions work perfectly does not point to a battery-related problem IMO.

You can save time and avoid further head-scratching by hooking up an OBD reader and reading the trouble codes. Take it to an independent shop or dealer service dept. if you don't know what you're doing with a system tester. This could be as simple as a loose and intermittent wire connection or it could be as bad as a failing immobilizer module. Get a repair estimate and then decide what to do.

kilodawg

Thanks I'm going to trailer it to my shop tomorrow if it doesn't miraculously start. So I'll find out one way or the other. It's the fact that that there is evidence for either the immobilizer or the battery cables as being the problem.

I have had the immobilizer indicator flash occasionally over the past couple of months and also just this morning the last time I drove it before it wouldn't start.

However, I also did disturb the battery connections very shortly before my first no start issue (I failed to mention that I removed the original battery to detail the trunk just before the first no start).

My anxiety is in not knowing whether I have a $20 problem that I could fix myself tomorrow. Or a $2000 problem that may have me out of my car for two months...

techman1

Go jiggle the ground cable and see if it starts.

kilodawg

Ok the latest. I got to work this morning and reconnected the battery, jiggled the cables and went to try and start the car. This time however I noticed that the immobilizer icon in the clock did not illuminate at all when the key was inserted and turned prior to pressing the fob and of course there was no start. So it's looking like the immobilizer has hard failed.

Today I try and get the car to my wrench but the future isn't looking too bright. With part quotes anywhere from $980 to $1450 along with a one to two month wait this seems like a nightmare scenario. Did I mention that this is my daily driver?

I tried looking on DC Automotive, Parts Heaven and LA Dismantlers web sites for used parts but nothing appeared to be available. Any thoughts on how to proceed now would be very much appreciated. I will regularly keep this thread updated until it's ugly conclusion because at best it will be helpful for somebody else in the future...

kilodawg

Latest update. I went back and tried to start it again. Still no joy but this time the immobilizer icon returned in the clock and cleared with the fob as normal. I tried this and repeated it a few times over the next 15 minutes.

The saga of trying to track down a replacement immobilizer gets worse though. Now I'm told by my local dealer that back order could be anywhere from 3 to 6 months.....

deekay911

Did you try calling LA dismantlers? Their prices suck, but that means they usually have plenty of stock..

993/907

There was a thread a month or so back which detailed a way to re-wire around the immobilzer.

Lorenfb

"There was a thread a month or so back which detailed a way to re-wire around the immobilzer."

Not possible!