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Evap code related to random loose piece?

2002 Pontiac Sunfire (Silver) ~119,000 Miles. From Michigan.



I have a (repeated) evap code reading of my Check Engine light. From what I understand the first thing to do is to change the gas cap and if that doesn’t work, take it in for a Smoke Test.



I purchased a new gas cap last night and thought I’d look under the car just to get a better idea of what’s under there.



Looking under, I found a loose basket-weaved type of thing just dangling from my exhaust system. It’s not currently attached to anything. Is this related to the evap code? What is this thing?



Check out the picture here: http://www…968832373/

What you’re seeing is a piece of insulation meant to keep the heat of the exhaust system away from something. The insulation is coming apart and about ready to fall off.

I don’t think it’s related to the evap system code, but it would be nice to know where it came from.

That is a form of heat shielding related to the exhaust system and has nothing to do with the evap code or system.

Before going for a “smoke test” btw, you can just inspect your evap system for leaks or breaks. Try Autozone’s repair guides to get a view of the components (www.autozone.com), but in general there is a black canister buried - probably deep on the driver’s side - of you engine compartment. In and out of it are little black hoses. Try to get a look at those and follow the hoses from the canister to their destinations. Look for splits, breaks, etc. Use you nose while you do it. If there’s a leak you should be able to smell gasoline fumes.

Now that you’ve both confirmed that it’s heat shielding/insulation, how critical is it that I get this checked out? I’m not sure how long it’s been loose, but can it wait 1-2 weeks until I’m able to get to my father-in-law’s house so he can fix it?

I’d worry more about the evap code than the heat shield. That insulation hasn’t been doing anything for a while. Another week or two won’t hurt anything.

The exhaust system isn’t leaking, is it? No unusual noises?

You can look around to see where it came from - some part of the other remnants of it are probably still attached somewhere, or at least evidence of it. I’m not an expert on exhaust systems and such, but my own guess is that you can likely drive around this way indefinitely. If you can find out where it came from and want to be sure, you likely can keep it where it is supposed to be temporarily w/ some wire. Then have someone look at it.

Check the areas above the muffler and cat converter next to the floor.

Your repeated evap code setting of the check engine light could be due to software parameters being set too narrowly, thus triggering the light for no good reason. This is a problem with some other makes of vehicles. Suggest you check with a dealer on possible factory bulletins that might cover this situation.