Engine Hesitation for 1-2 seconds.
 

I got a 2013 BRZ, with approx 47,000 km on it. This is the second time its happened, both times after a rain storm, so its cool and humid. I would be accelerating moderately (maybe 1/4~1/3) and at approx 3000 rpm, the engine would act like the fuel was cut off completely. After a second or so, the car would then continue on as if nothing happened, I would be able to go full throttle and the car would rev smoothly. This happened three times on my regular drive home from work. No Check Engine Lights or anything also when this happened, so not sure if I can even take it to a dealer.

Car only has a GReddy intake on it, everything else is stock.

Any ideas or anyone have similar experiences?

Was the slip light going on? When traction control kicks it, it limits the throttle. Since you said it was raining, I would assume the car detected wheel spin/slip and slowed the engine.

nope, no traction lights came on when this happened. The roads were drying at the time this happened the second time.

next time it rains look under the hood for excessive water someplace.

Have you adjusted maf scaling via tune for gready intake, pretty sure gready intake is a takeda clone and when i did scaling for those the fuel trims were up to 20% in places, good tune shouls see fuel trims lass than 5%. this can cause bogging and hesitation issues

Its likley intake related if maf scaling nor adjusted.

Cold weather causes fuel trims to drift as well

Did you get your last tank of gas at the same station you usually do ..... ??



humfrz

I've had this happen randomly too, but I think it's only happened in the first part of my drive so I just attribute it to the car not being warmed up and fuel trims or something being off. I'm on OFT stage 2 91 uel. It happens to me around 3000 rpm too and I remember hearing about a DI transition happening around 3k rpm, maybe it's noticeable during warmup on certain days :iono:

Not exactly, but there's only a certain set of gas stations I visit regularly since they are either close to work, or close to home. But it is the same "brand" and grade.


As for getting a tune just for the intake, it seems like a bit of a waste, but at the same time, i was also planning on getting a tune after I get headers/exhaust done.

Interesting note about the DI switchover point. I'll look further into that as well.

I'll try to keep this post updated if it happens again and/or I get some more solid info.

I have had the engine act very strangely with bad gas. Some ethanol dry gas additive clears it up in a fillup. Can't hurt, and it only costs about $5.

The switching from pi to di is more a transition than a switchover in normal operation see below

The car does run full port injection on startup till i think coolant get to certian temp then switches to using the pi\di ratio maps below their are 3 cold,warm , hot but all usually have same values.
Its engine load vs rpm based not just straight rpm


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