i replaced the exhaust on my 92' eg4 civic 1.5lsi import, there is no cat or secondary 02 sensor on car and since then i've lost acceleration and top end speed, also idle's roughly there's a slight miss.... why has happened???
Since a 1992 model is OBD I you probably won't have a downstream (secondary) oxygen sensor. But as far as I know you definatly should have a catalytic converter. Perhaps a previous owner (illegally) removed it. That may be causing your driveability issues. Without a catalytic converter you might not have the proper back pressure in the exhaust. This will cause an engine to run poorly. Is your "check engine" light on? If so, what trouble code(s) do you have? HTH. -Jim
your cat shouldnt affect it. just makes it louder. do you know how big the tubing is? like 3inch or 2.5 inches. if its 3 inch you may lose power. did you replace the exhaust manifold with a header? did u use the same o2 sensor if you did change to a header? changing your exhaust should only make it a touch quicker not really noticeable but still adds flow. there is legal ways of removing your cat say if your exhaust rusts conveniently arount the cat you can cut the cat out and say it rusted out.
how long ago did you replace the exhuast and which sections did you replace? the header all the way back or just after the headers? as mentioned previously the tubing size can play a factor because there isn't enough back pressure. so maybe your tubing is too large for your car. check for exhaust leaks
All the asnwers up above are correct. Its all about the back pressure. You can run with or with out a cat it just depends on the diameter of the exuast pipe your running. Also, what other HP upgrades have you done? Me personally I would run it with a cat even though its probably LOUD your losing power. .
Looking for a Used Civic in your area?
CarGurus has 77,526 nationwide Civic listings starting at $1,200.
Search Honda Civic Questions
Honda Civic Experts