Hick-up around 3K rpm... closed loop?

[Ratkiller]

I've only had my car for a few weeks now, but I noticed at around 3k rpm, with little throttle, just cruising, there is a little hick-up or hesitation. I've never experienced this in a car before, but I have seen and felt this in performance motorcycles.
Especially in newer bikes with emissions being a big concern now-a-days, there is a closed loop area in the engine software that can not be manipulated very easily, usually under 5k rpm. On some bikes when you change the exhaust or intake, the computer can't or won't compensate for the added air under 5k rpm. When riding and even on the dyno you can see and feel a slight hesitation when the bike surpasses the closed loop rpm range . My car feels the same why.

Or am I just nuts????

Sponsored

 

[Fenix]

Do you notice it with the engine warm or cold or both?

I notice a small dead spot (hesitation) around 3k before the engine is up to operating temp. Once warm it goes away so I assumed it was something in the ECU.

 

[Ratkiller]

Happens when cold and warm. I did notice when warm (head @ 205), it sometimes happens at a higher in the rmp range, like around 4K.

 

[Terminator2]

I've only had my car for a few weeks now, but I noticed at around 3k rpm, with little throttle, just cruising, there is a little hick-up or hesitation. I've never experienced this in a car before, but I have seen and felt this in performance motorcycles.
Especially in newer bikes with emissions being a big concern now-a-days, there is a closed loop area in the engine software that can not be manipulated very easily, usually under 5k rpm. On some bikes when you change the exhaust or intake, the computer can't or won't compensate for the added air under 5k rpm. When riding and even on the dyno you can see and feel a slight hesitation when the bike surpasses the closed loop rpm range . My car feels the same why.

Or am I just nuts????

Car is always in closed loop once O2s reach 150* which won't take long.

 

[Terminator2]

Do you notice it with the engine warm or cold or both?

I notice a small dead spot (hesitation) around 3k before the engine is up to operating temp. Once warm it goes away so I assumed it was something in the ECU.

Emissions related imrc setting (closed which acts like a mini choke) and emissions reduction cam settings.

 

[MagneticMan]

I got this too and noticing it with the Ford Power Pack 2 tune, it's minor but annoying

 

[Braski]

It's the variable valve timing.

 

[Terminator2]

It's the variable valve timing.

Combo of that and the IMRCs

 

[MagneticMan]

is this anything to worry about and can it be eliminated?

 

[markmurfie]

Car is always in closed loop once O2s reach 150* which won't take long.

The way he described the motorcycles is similar to the way our cars work. Its in closed loop most the time, but in certain modes like cold start up or OP mode, WOT or close to it for those unfamiliar, React./ after decel right after you let off the throttle, Ect. its in open loop.

So there are transitions and where these transitions are can easily be moved, but things would need to be pretty bad for the ECU not to compensate enough for you to feel it. Hiccups/ hesitations are usually caused by an ECU limit usually from bad torque values or just IMRC and VVT that are not smooth transitions. With how dynamic the ECU can be its time consuming to give it freedom and make every scenario perfect. Most after market tunes sacrifice this ECU flexibility for the gains they achieve. You end up with a car thats powerful and smooth, but the ECU doesnt have any chance of finding more power in certain situations or keeping your engine safe in others.

If OP can datalog and get revisions I would suggest going down that path, If not and another tuner is not an option then it is what it is.

Sponsored