Join Date: Oct 2016
Location: St. Catharines ON, Canada
I recently did a valve check on my '15 with 27,000km (16,700mi). All valves were within spec, although the exhaust valves were close to the tight end of spec, so I bumped them up to the top end. I also changed the air filter for the first time since new and it was quite clogged. I checked the TPS calibration before putting everything back together too, but it was bang on.
I had been noticing a slight hesitation, and a rich mixture smell as well before all this work, but that seems to have cleared up since. I believe it was mostly the air filter at fault. These FI systems lean very heavily on the TPS and IAT to calculate the injector pulse width. If the air flow is restricted the throttle angle will be exaggerated in relation to the actual air flow, causing a rich zone at the beginning of the throttle curve. Then the O2 sensor picks up the rich burn and the ECU leans the mixture just as the engine vacuum finally pulls air through the restricted filter. Now there's a lean spot just as the engine should be picking up steam.
Anyway, check that filter, and while it's likely not a panic, you might want to start making plans for a valve check in the next few thousand miles!
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