Long story short, the city didn't seal a gas shutoff valve cover properly so this large cast-iron cover was sticking out of the road waiting for my poor Prius. It dented my exhaust line to the point where its pinched it almost entirely, and on top of that it made a fairly large dent in my gas tank. Since the exhaust is pinched-in tightly with rebar bent onto it, its now making a horribly loud vibrating noise. I guess its the rebar hitting the vibrating exhaust. Two questions: If I bend back the rebar to give space for the exhaust line and determine that there IS in fact exhaust airflow, is the car safely drivable? Or is any kind of dent in the exhaust a bad thing? Insurance quoted me $2,600 in damage....
Free advice is worth what you paid for it. That said, Here's my $0.02: Lets talk about the biggest possible safety issue first; the gas tank. Your avatar says you have an '09. That means there's a bladder inside the tank. That would mean that if the tank were holed but the bladder was intact, there wouldn't be a visible fuel leak. However, from time to time the HSD does a vacuum test on the fuel tank looking for leaks in the bladder. If a slight vacuum can't be created in the space between tank and bladder, as a minimum a code will be "thrown" and logged. I'd also expect that a msg might appear on the MFD to take the car to a dealer ASAP… but it might just make the car un-startable. For future safety and peace of mind, even if the tank isn't holed now it should be replaced... who knows if theres now a rough surface on the inside of the tank rubbing against the bladder --> trouble in the future. The rattle in the exhaust could be the rebar -- Where'd that come from? -- vibrating against the exhaust or other parts of the car. It could just as likely be the exhaust pipe vibrating against other body parts because it has been torn off one or more of its mounts… not good. The exhaust system is more complex than just being a piece of pipe. Every turn or change in diameter/cross sectional area, bigger or smaller, sends pressure waves back towards the engine. which also means back through the Cat Converter. We can't say with certainty what the dent(s) in your exhaust may cause; it could result in exhaust gasses be pushed back into the cylinder, or it could result in the exhaust gasses be pulled out of the cylinder. In either case, that condition isn't normal and when the engine monitoring algorithms sense the change, it will try to make things right. However, I'd expect a rough running engine which will throw codes. (And then that might just make the car un-startable.) Maybe not an outright unsafe condition, but definitely something that should be fixed ASAP. There could also be as yet undetected cracks in the exhaust pipe. IMHO, the bottom line is; get the car fixed ASAP. Since there are questions as to possible safety issues, you should have the car transported to the repair facility on a flat bed truck. Let your insurance company fight it out with the city as to the city picking up the tab.
i bought my second prius from someone who had either run over a rock or large block of ice. I had it inspected by a Toyota dealership who put in the report to replace the gas tank due to a dent and to replace the headlight level sensor which had a snapped arm. The technician than took me aside and told me in secret that he was almost certain that the rubber bladder inside was undamaged since there was no visible gas leaks, and to forgo the repair. If you can get the city to pay for the damages the dealership will just replace everything that was damaged, otherwise you should post some pictures so priuschat users can help you make the car drive safely and reliably.
Very sound advice! This sounds like something that might be way more complicated than I think. Probably best to just forget saving a little extra money and get it diagnosed thoroughly. Thanks for your suggestions!
This is something that you should definitely have professionally diagnosed and fixed. While it might look OK if you try and fix it there could be problems down the line - two that come to mind are an exhaust leak which can be deadly or issues with the car passing inspection if the exhaust is not functioning at 100%. This was not your fault but rather caused by the negligence of either the city or a contractor who was allowed to work on the gas in that area - your insurance company really should take car of the repairs and then follow up on their own with whomever messed up - perhaps they just need a gentle nudge to have them make it right.
