1. Reasons to replace old hatch seal
Most of the 944 cars are running for decades and seals are degrading over time.
If you can smell fumes in the interior while the side windows are slightly or tottaly opened, this might be the problem.
It is usually rear hatch seal or the seal under the back lights.
2. Purchase list
You have two options:
100$ USD – Original Porsche rear hatch seal: 94451204301 / 94451204300
60$ USD – Aftermarket rear hatch seal: Ebay
I strongly recommend buying original Porsche rear hatch seal.
Aftermarket bought on Ebay has different shape and is made out of cheaper material.
My own experience with the cheaper seal it lasts only for about 4-8 months.
I will start tearing near the top handles and stop sealing near the locks.
3. Comparison betweet seal versions
4. Hatch seal installation
It can be a 20 min or a 2 day job depending on your chassis condition.
1) Remove old seal
2) Clean the chassis and use IPA or another degreaser
3) If you have found any rust, remove it with a steel brush or a dremel
4) Use degreaser again and apply rust converter
5) Start installing the seal from the middle – between the locks
6) Force the seal to the corner with one hand, to the chassis with the other
7) Put the endings next to each other
8) Cut one of the endings with cca extra 0.5 cm
9) Put inside one of the endings the connecting tube
10) Connect the endings and put the seal on the chassis