Confused Turtle

Ok so after a bunch of diagnosing I've determined that my immobilizer needs to be replaced. How do I go about doing that? Can I just buy a new one and throw it in or does it have to be programmed with the key that I have?

Starter986

Someone will correct me if I'm wrong...

The replacement immobilizer will have to be the exacxt same number as the one currently installed. Absent that... you'll need a whole new everything... immobilizer, DME, etc. This has been covered many, many times... which is from where I'm recalling my memory.

I read every single new post on the three forums I follow. Even if it's not something that applies to me or my car... I read about it... never knowing when that 'tidbit' of information might help me.

Try it.

BillC3

The immobilizer is the central component of the whole system. The immobilizer and keys need to be programmed into the ECU or the car won't start. Any programming requires a PIWIS system, so you'd have to go to a dealer or independent Porsche shop that has one.

The only way to avoid going to a dealer or shop would be to buy a full replacement set from a junkyard -- immobilizer, ECU, keys, ignition switch and door locks. Then, just swap all the parts over.

Or, you can buy just the immobilizer and the ECU from a junkyard, install them and tow the car to a dealer/shop to have the keys programmed into the system.

The least-intrusive way is to buy a replacement immobilizer and go to a dealer/shop, and have it programmed into the car. If you're going to a dealer, they will probably require that you order the immobilizer from them -- ask them before making any purchase.

Confused Turtle

I did research on it for about 2 days. I search this forum and the 986forum as well. I kept coming up on conflicting information, hence why I asked myself. However, I do appreciate you taking the time to respond to my post.

Confused Turtle

Please correct me if I'm not understanding this, I wouldn't be able to just buy an immobilizer and have it programmed into the system? There is a dealer near me, I will give them a call today and ask about programming. Thank you for the response.

BillC3

Yes, you can buy just the immobilizer and have it programmed in -- see the last line in my previous post. The big "however" is that most dealers will not install or program parts you bought elsewhere; most require that you buy the parts from them before/while they do the work.

Alternatively, you can contact ECU Doctors and ask them about repairing or replacing your immobilizer. You'll probably need to send them your ECU, but could be cheaper and/or faster than a dealership.

NuttyProfessor

Based on my experience, you will have to tow the car with all keys to the dealer. Be ready to pay the full price of admission. That means, replacement and programming of a new immobilizer unit.

Dllrd23

interesting that you mention the door locks too. Makes sense but even the ebay’ers are not offering the door lock cylinder. I would be interested to hear thoughts on if it is absolutely needed or not.

BillC3

If you don't mind carrying around two separate keys, one for the ignition and one for door lock, then it's no big deal. Or, you can just have the door lock cylinder re-keyed to match the new key -- the door lock is completely mechanical, so doesn't require reprogramming for a new key, just new wafers to match the key. In fact, re-keying is pretty simple if you have access to an assortment of wafers, or are willing to mix, match and file-down the existing wafers (which brings a risk of reduced security).

The other option is to carry just the new ignition key and hope that your battery never dies when you are away from wherever you stored the (old) door key. However, I'm not that lucky -- with my luck, the battery would die the first time I was away from the house and there was no one home to bring me the other key.

Confused Turtle

I didn't think about the door locks, but I did manage to find a key, immobilizer and DME for the car. I figured I'd just switch the blades around that way i wouldnt have to change the locks or the ignition cylinder.

BillC3

There's another option that doesn't require re-keying the locks. And that is to pull the RFID "pill" out of the new key and transplant it into your old key. This way, the immobilizer will recognize the pill and the locks will still mechanically work with the key.

elgy

What he said ^
The locks work with the blade of the key. The immobiliser works with the pill in the key fob.

Confused Turtle

So i did replace it with a used immobilized with key and DME. Still having the same issues except for I don't need to jump the relays anymore. Sill will crank but not start. I have a new CPS and ignition switch. I checked the resistance on my CPS and it its really off from what I measured on a known good one. So hopefully after switching these out it'll fix the issues. If they don't work, then I'm not sure where to go from there.

Confused Turtle

Update* I've changed out the immobilizer, DME, ignition switch and the CPS and it finally cranks over. It runs really rough then dies but its finally running. Just gotta get it to run a bit smoother and I'm all good.

Starter986

Good to hear! Now just some fine tuning.

You do query members on other, more robust forums... yes? No? You don't stick to just this forum... do you? There are other 986forum dot com.

Keep reading.