Finally got around to doing one of those small but satisfying jobs on the car - removing the exhaust rattle - particularly noticeable at idle. (940GL, B230FB NA motor)

Recently when idling beside a wall at a drive in takeaway place, the sound reflecting off the wall made me realise how rattly my exhaust had become.

An examination underneath showed that I had 2 cracked welds on a sort of gusset piece several inches long that is welded onto the bottom side of the exhaust, immediately behind the catalytic converter. (It looked like an original part of the exhaust system as the gusset was curved and formed around the exhaust in a way the spoke of factory jigging (?)) To get at the front weld on this gusset, it was necessary to remove the perforated metal heatshield that went around the bottom half ofthe cat. When the heatshield was off, a whole heap of small stones that had worked their way in between the cat and the shield were removed.

With the battery earth disconnected, and using a MIG welder, a couple of small tacks were necessary to fix the 2 cracked welds. The heatshield was refitted, using copper anti-sieze on the bolts. I intend to drop the heatshield every time I do an oil change from now on, to get rid of any new stones - it's such a quick job if the 4 bolts run freely.

The end result is no rattling at idle from the exhaust. Also, a transient rattling that I used to notice when accelerating is also now gone.

The ratio of result achieved : time invested is very high with this job.

John Marshall
1994 940GL wagon
Christchurch NZ