Convert dual exhaust on 99 sunfire gt to single?

On most cars, if it is the original muffler, it will be welded into the exhaust system. You would need to cut the muffler out of the system with a pipe cutter, hacksaw, or torch to remove it. Aftermarket mufflers are installed with clamps. Those must be removed in order to remove the muffler. Even then, the clamps will crimp the pipes together and you often have the chisel the muffler collars off the exhaust pipe to remove.

You should check your exhaust for a clog of some kind such as a collapsed catalytic converter,Muffler or bent pipe or even something put in the tail pipe. also air filter car will start and run with clogged air or exhaust at idle but will starve out when idled up at all

its important to have the right amount of backprettiar in your exhaust, so if going from 2 mufflers and 2 pipes to a single one would need to enlarge the size of the pipe to compansate. or it wont breath right and end up gutless.

normal mufflers have a weep hole but if the muffler is rusted or loud replace

When gasoline is burnt the products are carbon dioxide and water:- 2C8H18 (gasoline) + 25O2 (air) ----------> 18H2O (water) + 16CO2 (carbon dioxide) If you take short trips the water content will condense in the cold exhaust pipe and collect in the muffler boxes (silencers). At a certain point the water will fill the mufflers, overflow and begin to dribble out of the exhaust tail pipe. It is worthwhile to occasionally give your car a longer run to allow the exhaust to become sufficiently hot and to evaporate all the collected water. The water is acidic and hastens the corrosion of the exhaust pipes.

It depends what is causing the leak. If there is a hole in the pipe, you may be able to cut the pipe and install a coupler with a couple of clamps. If the hole is at the point where the pipe is welded to the muffler, then you have to cut out the muffler and replace it.

Single exhaust, bolts on at the Y pipe and from there back the system is held in place on rubber hangers.
Simple install once you get the bolts removed at the Y pipe.
Dual exhaust is the same but X 2.
If you're not going to replace the Y pipe then you'll have to cut the pipe to the proper length and clamp or weld the muffler on.


http://www.walkerexhaust.com/catalog/ExhaustCouponScreen.asp

it is against the law to remove a cat converter and replace with straight pipe

Most local muffler shop will inspect the exhaust for you for free and if it's just a broken hanger, they can replace it for around $45.00. You could always go to the auto parts store and buy a new hanger, but your going to have to get under the car and remove any old parts left over from the old hanger and place the new one. Good luck and hope this helps. If you go to Auto Zone they can help you look up all the hangers for that car or any muffler shop as mentioned earlier. 

Good Day,

Most aftermarket exhaust systems are cat-back. You defiantly need to keep the cat to comply with local emsisions regualtions. However you can remove the mufflers and replace them with high flow mufflers or resonators. Try to replace them with something not too loud so you are in accordance with noise laws in your area. I have a 2000 s10 with no mufflers, just a cat then a y-pipe to make it dual with two resonators coming straight out the back, I live in the states and made sure this sytem was 50 state street legal before I purchased it. I suggest you do the same to avoid harrasment by the police.

Good Luck

Hope this helps.