I was recently given a 2003 Honda Civic by a family friend. I had to get a muffler replaced on February 10th 2016 and mistakenly told the mechanic that the car was a 2000 Honda Civic as opposed to a 2003 model. I made this mistake because my previous two cars were 2000 models, and I had a mental lapse. There is nothing obvious wrong with the car, I just realized my mistake when I had to look in the manual for the ideal tire pressure today. I remember the mechanic made a comment about how they had to weld on the new muffler, and I thought that was strange. So my question is, do I need to get this fixed immediately (or at all) or is it ok for a 2003 Honda Civic to run with a 2000 Honda Civic muffler?
My car has 180000 miles.
My car has an automatic transmission.
Your present engine has about 6% greater displacement than the engine used in the 2000 model year (1.7L versus 1.6L). Greater displacement means there is a higher volume of exhaust gases flowing through the system. As a consequence, the muffler used in 2003 was designed to be 15% larger in volume compared to that used in 2000. (The 2003 muffler is an oval 15 inches long by 7 inches by 9 inches. The model year 2000 muffler is an oval 13 inches by 7 by 9. That means there is 15% more interior space in the 2003 muffler.) The difference between the exhaust flow in the two cases, while not "trivial", is probably not significant enough to warrant changing the muffler particularly if you are not noticing any adverse effect on vehicle gas mileage. If you getting the EPA rated gas mileage or better, I wouldn’t worry about it. However, if you want to absolutely confirm the acceptability of this arrangement, simply measure exhaust back pressure. If back pressure at idle is around 1.5 PSI and holds steady and pressure rises to 3.0 PSI at 2,000 RPM and holds steady, then you are definitely in good shape (no restriction) and you need not change anything. Despite everything, if you do want the muffler changed out simply request exhaust system service - muffler replacement and the responding certified mechanic will get you restored to the status quo ante. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.
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