Drw814

Hello all, I have a 1987 944 turbo. I bought it earlier in this year and have done some service to it. I had the timing belt service done, new spark plugs and a few other misc. items. Recently I have noticed the car is not building much boost. On the factory boost gauge it only gets to ~1.1-1.2 bar. I know the car used to get up to at least 1.5 bar a few weeks ago, so now I am looking for root cause. I have checked all the hoses and lines and none are loose or visibly damaged.

Since I bought the car it will sometimes break up especially at higher rpm. That was the main reason I put in new plugs. Now after driving the car more it feels like it is running out of breath. Now I am trying to link this feeling with the lower boost pressure. I checked the air filter and related intake components and they all seem fine, which leads me to believe it may be a clogged cat? I noticed after a long drive a couple weeks ago there was a length of fiberglass string/packing hanging out of the tailpipe. To me it looked like cat material. I pulled the little length out with some pliers. Is there any way to verify if it is the cat? Anything else I should check? Thank you.

Spdygon

Fiber material is from the muffler not the cat. Iv heard of several owners finding the fiber material com apart in the muffler and clog it up.
start there first

Drw814

Well I think I may have found my problem. I decided to shine a falshlight down the exhaust pipe today and it looks like the muffler outlet is completely clogged with fiber material. Now working to clear it out.