Hello from SC newbie! I have had my -89 SC for about 3 month and starting about 1 month ago idle vacuum has been dropping slowly from 19-20 to 14 and now performance is really poor. Boost comes really quickly but it's pain to get car to go even 60mph
Top of engine was build up by last owner and I just changed fresh 255lph fuelpump & filter (they did not make engine any better, so likely it is not fuel problem)
KOEO & KOER test did not give any alarming codes. I also did intake track pressure testing to see if there were any boost/vacuum leaks, only "hissing" came from EGR gasket, and it was too small to create my troubles I think.
Downpipes, cats & rest of the exhaust is quite fresh (2000 miles..) but from what I have read from forum, my cats could be clogged..
Any ideas to check cats or do I just replace them with pipe.. or if you think any other reason my car is behaving like this?
Thanks!
Top of engine was build up by last owner and I just changed fresh 255lph fuelpump & filter (they did not make engine any better, so likely it is not fuel problem)
KOEO & KOER test did not give any alarming codes. I also did intake track pressure testing to see if there were any boost/vacuum leaks, only "hissing" came from EGR gasket, and it was too small to create my troubles I think.
Downpipes, cats & rest of the exhaust is quite fresh (2000 miles..) but from what I have read from forum, my cats could be clogged..
Any ideas to check cats or do I just replace them with pipe.. or if you think any other reason my car is behaving like this?
Thanks!
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