Hey all,

Quick question. I have a 2009 V6 outlander 105,000KM. A few weeks ago, one of the heat shield was rattling, so I went under the car and basically cinched a bracket around the whole pipe (including the upper heat shield), and tightened the whole thing.

The next tank of gas my mileage dropped to levels I have never seen before (14mpg). Not really driving any differently, and not noticing any new noises or differences in sounds.

If I tightened that bracket too much, is it possible that I pulled the exhaust pipe out of alignment with something, causing a leak at a seal or something, hence the bad gas mileage??

The heat shield that rusted was on the exhaust pipe about right in the middle of the car (there is an upper one which is still ok, but the lower one rusted)...

Thoughts?

 

Possible that you got it too tight and [partially collapsed the pipe, b ut I can't see that happening unless the exhaust system was really rusty and corroded.

 

The most likely cause would be a damaged O2 sensor or the wire for it.