Rev Problems

[Digital Jedi]

Hi All;

I own a 2K NSX, and am having two difficulties with it that my dealership can't seem to solve. The first is when cold shifting from first to second produces a nice grinding noise. The second, is that when shifting at lower RPM, 3K - 4K, my RPM hangs for a second or two while the clutch is engaged. I asked the dealership they told me it was normal and the engine was burning off excess fuel to meet emission requirements. I don't believe it. If anyone has a Y2K or 2K1 NSX I would love to know if you are also experiencing these problems. Thanks.

 

[Edo]

The grinding noise would be from bad Synchro's... I had a brand new Cobra Mustang that did that no matter what I did. They replaced the Synchro's and all was well after that. Why the Synchro's were bad from the factory I dont know.
The engine rev's hanging might be from some sort of problem with the drive by wire throttle..didnt they have some sort of CPU update for those?

 

[Digital Jedi]

I had the synchros replaced along with first and second gear last week. No difference. I spoke with anohter 2K NSX owner, aparently he has the same difficulties. Emission management system is to blame for the revs, the slight grind when shifting to second is the same for him. Who knows. Thanks for your comments.

 

[rquintero]

Hmm - my 2K does not have either of those issues.

But then again you and I probably have a different definition of "cold".

Does the "RPM hang" happen in all gears? Are you saying that while you are depressing the clutch and before you disengage it the RPM's just sit up there? What are you doing with your right foot?

 

[akira3d]

I've never noticed anything like that with my 2K either. Smooth shifting all the way.

------------------
--akira3D ('00 NSX-T red/black #113)
"Reality is better than the dream..."

akira3d.com/nsx

 

[David]

This is a long shot, but it is also possible that your clutch may be adjusted so that it is not disengauged completely when you depress the pedal. If it is at the point where it is BARELY touching when the pedal is fully depressed, you would only really notice a problem shifting into first and maybe second. It can be adjusted at the pedal cluster a bit, so you might want to try that. If this is the problem, however, it would probably not only be an issue when cold.

[This message has been edited by David (edited 13 April 2001).]

 

[Digital Jedi]

Thanks for all the input. "Cold" means the first few shifts after starting the vehicle and allowing it to reduce idle on its own. I have had my foot to the floorboard on the clutch and still... Revs hanging occurs in every gear unless I am accelerating hard. If I drive it like a Prelude (slap me) the RPM will hang. I have deliberately gone through the shifting process; foot off the gas, clutch in, shift, clutch off, foot on the gas and still have the same problem. Bizarre. I thought maybe David had different emission standards being from Texas, but rquintero and akira3d are in Cali, strictist emission laws there are so... Maybe my dealer will eventually figure it out. Thanks.

 

[rquintero]

Actually, I'm in S. Florida and I'm sure we have standard emissions guidelines.

I actually tried to make the rev "hang" thing happen this morning but couldn't - actually the second I even lightly depress the clutch the revs start dropping as they should, no spike or anything unusual.

Have you tried a different acura dealer?

Good luck,

Ralph

 

[queenlives]

digi:

i've had the same issues with my '00 car on a relatively intermittent basis... not a real problem in the overall scheme of life.

be well.
hal

 

[nsxbadboy]

On my 97 ,I have the same problem with the hanging rpms.Ive heard it is due to the drive-by-wire throttle and I believe that because my 92 didnt do that at all.I have almost completely solved it by purchasing a lightened flywheel.Its barely noticeable now.(High rpms only)As for your grinding,try changing your trans. fluid to synthetic(red line).Although I dont have that problem with my NSX,I had it with my RX7 and synthetic fluid solved it.
Hope this info helps a little.

Joe

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97 NSX-T
93 RX7 Touring

[This message has been edited by nsxbadboy (edited 16 April 2001).]

 

[sjs]

1-2 and 2-1 is very notchy (grind if I force it) when the temp is below ~35 until the transmission warms up. Changed oil type once and only made it worse. Now it's warming up again so I don't care until next fall, when I'll go back to Honda/Acura MTL.

 

[andymlow]

I have a '00 with 2500 miles. I too have the rev hang and a very notchy 1-2 shift when cold (ambient temp 70's, car not warmed up). I think the shift problem is present sometimes when warm too, but I'm not sure. Seems like engine management software is responsible for the revs, and not something mechanical. Just my thoughts. Will ask my dealer to look at it next week.

 

[andymlow]

Let's not give up on this problem yet. I find it very annoying and really distracting from enjoying the car fully (especially when I know ther are cars not doing this). My dealer gave me the "we couldn't reproduce it" response, which doesn't mean jack. There is most definitly a synchro problem and a throttle management problem. I can't believe it is driver related since several of us have the exact same desciption. Can you say TSB?

 

[Digital Jedi]

My dealership is replacing the synchros and first two gears on my NSX again. The regional Honda rep has no idea why they grind but they are going to look carefully at the vehicle to resolve the issue.

As for the RPM hanging, my dealership managed to contact someone from Honda who has extesive experience with their products in a racing environement and he stated that the engine management system burns excess fuel when the vehicle is driven at low RPM to meet emission standards. I am beginning to believe this for two reasons. First, if a vehicle is tuned improperly and is running a bit rich it would explain why some NSX's do this and others do not. Also, fuel additives can contribute to emissions and may help to explain why some vehicles have this problem and some do not. I am going to replace my CPU with an aftermarket unit (Mugen) I will post my findings afterwards.

 

[Bruce]

Jedi,
It is clear from your first post that your dealership is the wrong place to get anymore additional help.Call Honda/Acura customer service dept.Used properly they can be your best tool,very powerful dept.Ask customer service if a "Service Bulletin" has been released on this problem including earlier models. Notify them of your problems in detail and and about others which have already come foward on this forum.Even mention the NSX Forum, I have in the past. Info like this is vital to them.Complaining about your problem is one thing. Informing them of several of the same problems and possibly more and potentially dangerous to other NSX owners,is a serious matter(hanging throttle).You have a 2000 model, that still under warranty isn't it?I had an experience with a `95 NSX which was out of warranty.Problem was unheard of in that year untill I brought it to their attention.Dealerships don't make money on warranty work...some may choose not to report to manufacturers at all.With the help of info gathered from this forum and constructivly speaking,I recieved full cooperation.Heck, tell 'em Lud sent you!(kidding)Even though '95 NSX was out of warranty,they still covered all cost.High-end Japanese manufacturers, (Acura,Lexus,Infinity) strive for quality customer service.If your dealer isn't, then give manufacture a chance to prove it.

 

[Andy Buzz]

My 97 revs a brief moment also. Based on the fact that many other NSXs with thottle by wire do the same, I subside this to be a normal or uncorrectable design flaw. The grinding occurs in mine until the trans fluid gets hot. The grind is not heard but felt through the shifter. I also believe that Amsoil or Redline synthetic will solve your problem.

 

[andymlow]

Well, I now have 3500 miles on the car and the shifting is smoothing out as is the clutch engagement in 1st. I still find the revs hanging, but it seems less annoying now that the other problems are resolving. I did do one track event at high rpm and that may have helped too. Who know?

 

[Digital Jedi]

I have had the gears replaced in my NSX a second time, no grinding occurs now, nothing but smooth shifting.

The RPM hanging is persistant, but I have been told that it is not "normal" by my dealership. If it is normal, then it is efinitley a design flaw as it is the only vehicle I have ever driven to have this occur.