Under hood parts made of PLA or ABS? Can they take heat?

I was just roaming through thingiverse and noticed the automotive section, I love modding my cars especially under the hood, but how are these people printing things out of ABS and PLA like spark plug wire holders and TFSI module brackets? The air under the head is exposed to extremely hot exhaust header radiation and hot air temperatures. Does anyone have any experience with using these printed plastic parts next to a car engine?

Maybe if you put the plastic bits up and away from the header or away from the cylinder head, you would be ok, but even the ambient air under there can approach 200-250F on a hot day and that can really soften a print.

Yeah... No. PLA softens at 50C and ABS somewhere around 85C

They may be printed as a prototype or for fun, but for functional use? No way. For an engine part thats actually exposed to that kind of heat, you want at least PEEK or Ultem. You can't print either on a "consumer" home printer.

What you could do is print out whatever you want to make, and cast it in something metal or such. More work, great result's I bet. This is what I mean, and the guy has a nice hour long video of his process with it. http://www.thingiverse.com/make:115127