Hey all,

With 2k2 6 spd almost broken in, I've taken a few 3/4 throttle runs to 4000 rpm, and I've noticed there is a significant amount of throttle hang with the car.

At first, I thought I was screwing up my shifts so I started to make sure I had my foot completely off the gas before touching the clutch, and the same thing was happening.

Basically, I take my foot off the gas, hit the clutch, and the engine stays at the same RPMs. It even seems to blip up a few hundred rpm sometimes.

Is this just me or is anyone else experiencing this?

 

The car does that to reduce emissions. Especially with the 2k2 drive by wire, engineers didn't give us total control.

 

Booooooooooooo on there part

 

Throttle hand is very common in modern cars as it is a way to reduce emissions. When the throttle snaps shut, a lot of unburn NOx's are produced. Car makers found out that by having the engine slowly come down in RPMs, these emissions are reduced significantly. This is accomplished by leaving the IACV (Idle Air Control Valve) open between shifts.

So, if this car is anything like the cougar, it is normal for the throttle hang. One way to combat this is to place a restriction in the IACV Bypass tube. To read more about this, click on the link below in my signature and do a search for "throttle hang" in the archived messages in every category. I also have a how-to on my website that details this simple solution that is easily reversable.

http://www.fastcougar.com/how_to/how...ttle_hang.html

There are some reasons why you may not want to do this. First, if given no way of breathing, the engine will be tempted to suck "air" past the PCV Valve and rings. This will cause the engine to stumble and die. However, I don't buy into this theory because the intake air is simply being restricted, not completely cut off.

 

Uhhh ... the 2K2 Max's throttle is not drive-by-wire, is it? The 2K2 Altima is but in everything I've read, both online and in Nissan publications, I've never seen it stated that the 2K2 is drive-by-wire.

It certainly doesn't feel like it is, anyway. The 2K2 Altima has a much more responsive and accurate throttle than the 2K2 Maxima does.

 

Try looking here http://www.edmunds.com/reviews/roadt...8/article.html

 

FWIW, my Altima 3.5SE 5-speed does the same thing. I don't like it either, but I guess that's the way it is.

 

My 2K2 throttle feels exactly the same as my 2K GXE did, including the throttle hang you guys are talking about. That's another reason I didn't believe the 2K2 went to a drive-by-wire. I thought this "throttle hang" was the notorious slipping auto tranny issue.

 

Ummm...look under the hood of your 2002 and tell me if you see any cables coming out of the throttle body



Dave

 

Shhh Dave... Don't let out the secret.

Stereodude

 

Yeah as fastcougar said this is probably done to reduce emissions. Us 00/01 5spd guys get the same thing. RPMs wait a couple of seconds before dropping when I depress the clutch and during spirited driving and quick shifts the rpms rise 200-300 rpms. So it is probably not unusal.

 

Your shifting too slow if you notice

It bugged me too when I first got the car, but I've grown used to it and it doesn't effect my shifting any. The car is finally starting to break in become a pleasure to drive. The shifter has smoothed out and the clutch is developing some "feel". The ECU isn't being so conservative either. I swear that it wouldn't let me run WOT for the first week and kept the mix overly rich.

 

i drove one and everytime i would shift the engines revs would stay up. i found it to be real strange. espically after getting out of my car which the revs drop almost immediatly. i dont like it at all.

 

Try my throttle hang fix ... the how to can be applied to almost any car that uses an IACV bypass tube and exhibits this behavior. If you don't like the result, take it out ... only takes 15 minutes!

 

I'm no car expert, could someone explain
what the disadvantages of not having the rpms drop down really quickly are? (other than using engine braking)

 

As they said a few posts above, it has to do with emissions. It keeps the tree huggers happy, but it ticks the rest of us off. It's hard to make quick shifts smooth with the throttle like this.