tct118

The other day while driving on the freeway my car lost power (gas pedal didn't work) and stalled. I could smell gas in the cabin but didn't think much of it at the time. I tried starting it back up but it would idle really rough and stall right away. I thought maybe it was the DME relay, but I just put a new solid state relay in. I was stranded in the middle of the freeway but after many attempts, I was able to get it barely running long enough to get to the very right. Even getting off the freeway was tough since the exit was a steep incline. Luckily, it stayed on long enough for me to get off. As I was getting off, I noticed fumes from my rear view mirror. Someone pulled up next to me to say there was gas spewing from my car!

After safely off the freeway, I realized the severity of the situation. I took off the intake air filter box and saw that the Right Rear Shock Piston Rod busted through the Rear Shock Mount and cut my fuel line! In hindsight, I shouldn't have tried to start the car. Every time I started the car or pressed the gas pedal, I was dumping fuel into the engine next to the exhaust. I'm also surprised the fuel line hose held together that long. Luckily the car didn't catch fire, I wasn't in an accident, and I was safe. It was definitely one of the scariest ordeals I ever had to go through.

3 weeks ago, the same thing happened on the rear left side. The left rear piston rod busted through the shock mount and dented my a/c lines. It wasn't as big of a deal as the fuel line, but just loud rattling noises and it took off some of the sound pad. The shop I had it repaired, said it was missing a washer between the rod and the shock mount and that's why it went thru. It is now towed to the same shop and it's waiting for a replacement fuel line and new rear shock mount for the right side. Once they disassemble it, we'll be able to see how it was installed and why it failed.

This is my first 964 and Porsche. Bought this car 1.5 months ago from a Rennlister and it's been in the shop twice plus this recent incident on the freeway. The previous owner had Bilstein B6 and H&R springs installed only 500 miles ago by a very highly regarded shop (same shop that did my PPI). I believe it wasn't installed correctly. I don't think there are any washers, bump stops, dust boots between the piston rod and the shock mount. It's just the piston rod to the shock mount directly. Has this happened to anyone before? Do you guys know the exact parts that need to be installed between the shock and the shock mount and in what order?

Appreciate any help and advice you guys can give me. Thanks.

-Tony

Marine Blue

HDA

Damn! Definitely scary...

LM964

Blimey. Very scary and close to no longer having the car at all. Never heard of this before. Would never have thought the rear mounts were a weak point or a potential for failure. When you had the other side repaired/replaced did they not check the r/h/s too for the same. Sounds like maybe an incorrect installation of those dampers(?)

Normandy 964

Very scary....you are definately missing the lower washer, see the exploded view below :

In your last photo we can see the washer 2, but washer 5 is missing.
If washer 5 had been there it wouldn't have punched through the top mount.

tct118

Thanks, Marine Blue!

Ya, it definitely could've been much worse... They were supposed to check the right side but after the shop owner left for Rennsport, the shop forgot to. When I went to pick it up, the manager told me that the washer was probably in there since that side hasn't failed yet. I did contact the PO immediately and he was supposed to talk to the original shop that did the install but I never heard back.

I agree, I'm pretty sure it was installed incorrectly. It's unfortunate that a small oversight can cause such a big problem.

tct118

Thanks for the info, Normandy 964. You're correct, that washer 5 must be missing. I talked to Bilstein and they said for the B6 all the OEM parts needs to be reused. So bump stops, washers and dust boots. They sent me this diagram which looks similar to the ones you posted.