Calling all reflash owners

Andex said:

While this is only speculation on my part, how can a third party account for all the different demands put upon an engine? Not unless they have access to all of Honda data which maps out the engine under different load, atmospheric and road conditions, and with different accessories operating. So the kind of situation that you experienced, with what sounds like a failure of the ecu to account for heavy A/C load, doesn't surprise me. As I said in another thread, I expect that third party reflashing will be incompatible with direct injection engines, because of that system's notoriously tight calibration requirements (to avoid carbon buildup in the cylinders and on the pistons).

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Actually, the carbon buildup problem that direct injection engines are exhibiting affects the valves, not the cylinders. In modern high compression engines, the valves cannot create a perfect seal, and some oil and gas make their way past the valve seats during the compression and ignition strokes. With port fuel injection, this isn't a problem, as the valves are continuously doused with gasoline (and the accompanying detergents), which doesn't allow the oil to stick and cause carbon buildup. However, with direct injection, no gasoline ever hits the valves, so the blowby eventually builds up carbon deposits on the valves and surrounding areas.

There are many software tunes already out for direct injection motors like those run by BMW and Audi, and they are producing some ridiculous gains with just a software tune and bolt ons. In fact, the direct injection engines have been proven to be easier to tune and more cost effective in terms of cost vs. hp gains. Because the timing of the fuel delivery can be precisely timed (i.e., not injected until later in the compression stroke), there is less chance of knock or detonation, so higher compression ratios and leaner A/F mixtures can be run, leading to greater performance and efficiency.

For example, take the new BMW 328i. It's 2.0T motor runs a 10.0:1 compression ratio with 18.9psi of max boost, generating a maximum of 240hp and 260 ft-lbs of tq. A normal port injection motor would have to run extremely rich to mitigate the chances of detonation, which normally kills gas mileage. But with direct injection, the motor can run much closer to an optimal A/F ratio, which allows the 328i to earn an EPA rating of 23city/34hwy. The Si, in comparison, is only rated 22/31, despite being smaller, lighter, and slower.

As far as trying to solve the carbon buildup issue, some manufacturers are turning to a port and direct injection system. Their new designs run mostly on direct injection for efficiency, but use port injection as well during certain circumstances, allowing the valves to receive a small amount of gasoline for cleaning.

and to the OP, if you have the clutch in while you feel that jolt coming out of gear, it's probably not related to the reflash. While the reflash adjusts the engine's operational parameters, if the clutch is in, the motor is totally disconnected from the trans, and wouldn't affect how the shifter feels going in or out of gear.

However, I can see an issue if you try to pull out of gear before fully depressing the clutch. Since the reflash removes the rev hang, once you let off the gas, the engine immediately starts engine braking. Because of the helical cut nature of the gears, any load on the engine, whether it be from acceleration or engine braking is gonna make it harder to move the shifter out of gear. So if you try to move the shifter before you fully depress the clutch, the initial resistance you feel before the clutch disengages could account for the quick jolt.