Engine delays deceleration between gear change

[Quench]

Have a problem with my 2000 Nubira manual 2.0ltr.
While driving, when I release the accelerator and press the clutch, the engine rpm holds for about 1 second before the revs starts to drop.

I suppose this is likely to be a problem with the "idle air control valve" (sticky?). Or is it some sensor?

Anyone else had this problem?

[benzino]

it sometimes happens if it's cold and it also sometimes happens if the engine speed is higher than the wheel speeds; i.e. usual on 1st-2nd gear change

it's a little annoying but I'm not sure if there's a solution

[Quench]

Ah so this is normal?

My Ford Laser was designed with this 'feature' so I disconnected it's idle up solenoid to stop this annoying behavior.

I might change a few bits on the Nubira and if there's any improvement, will let you know.

[PrecisionBoost]

The nubira 2.0 has a very heavy flywheel ( in my opinion ), there are other lighter alternatives, but it would really have be a huge annoyance to spend the money/time to switch out the flywheel, cluch and pressure plate over to the lighter design.

Converting from the "pot" style flywheel to the "flat" flywheel makes a huge difference in the feel of the engine, the engine responds quicker, it feels more powerful and it drops RPM off shifts very quickly.

I have multiple vehicles with the same engine family, my Optra5 ( basicly same engine as yours ) use to drive me nuts for the same reason you mention, it felt like it took forever for the RPM to drop, where as my 2.0L with the flat flywheel drops the RPM by 1500-2000 in a blink of the eye.

The 2.0L with the heavy "pot" flywheel is slow to respond ( up or down ) but it's smooth like whipped butter
The 2.0L with the light "flat" flywheel is lively but you really feel every jerk of the engine

At one point everything was so nice and light and lively ( additional components lightened significantly ) that I had a bad time in a bumpy parking lot.

Each time I hit a bump my foot moved on the accelerator pedal ever so slightly, causing the engine to jump up in RPM instantly, resulting in a jerk that again moved my foot on the accelerator creating another more severe jerk.

In short, there were times where I'd have to pull my foot right off the accelerator and let the car settle or the car would end up throwing me back and fourth like I was driving over dozens of speed bumps at 50 MPH


Needless to say, I'm probably not helping you much with this, but at least you know that the flywheel is partially responsible for your annoying problem.

[Quench]

Gee, I never would have picked the flywheel having any influence on it.
I know the slow engine deceleration is done on purpose to aid matching rpms with the transmission to make gear changes smoother, but it feels like it's over compensated here.
Oh well, with two people confirming I guess it's not a fault.

Thanks all.

[PrecisionBoost]

My experience is with the same engine, same ECU, just different flywheels.

As benzino said, sometimes it's worse depending on the factors he mentioned