If you haven't done so already, I'd clean out your engine bay. Start by pulling off the cover under the engine bay. Then cover the alternator, battery, air intake, fuses with a bag. The battery and fuses have a quasi cover, and the stock air intake is probably pretty well protected too. With a hose on shower spray down the entire engine bay. Then spray it down with a foamy application of your degreaser of choice. Let it soak 2-3 minutes and scrub any problem areas. Rinse the engine down, drying it by hand if you want to avoid water spots and then remove the bags and put your stock skid plate/engine cover back.
It should take you half an hour or so, and if it's stuff in the engine (perhaps rat crap burning on a warmed up engine) this will take care of it.
2012 SE Hatch - 5 Speed - Tuxedo Black
Engine: K&N Typhoon CAI, Magnaflow 2.25 exhaust 15072
Suspension: MS3 Springs, Focus electric RMM.
Audio: LC6i, Polk Audio db6501 front, db651s rear, db1040DVC sub, Rockford R600-5 Prime, Fatmat