RPM surge during quick shifts?

[Bobby C 01TA]

I drive my buddies 98 around alot but have noticed that during fast shifts, the rpms jump while going through the gears.. He said something about a recall on the ECU that hasnt been done yet.. would this be causing the problem? Thanks!

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2001 TA
1991 MR2

 

[nsxtasy]

At what point do the RPMs jump? When it's in neutral? (If so, it might be driver error.) When you're letting out the clutch? (If so, the clutch might be slipping, and need replacement.) Some other time?

 

[Markbert]

Take your foot off the gas while you press in the clutch?
J/K

 

[Auraraptor]

Acutally mine does that too....there was a recall on ecus?

but in mine, I think its because even though u have released the accel pedal, the car thinks momentayily that u still have it pressed slightly, so when u jam the clutch it bounces the rpms....its like a delay in the pedal from going up all the way or something

my 2c

 

[kenjiMR]

I think either mechanically or electronically this is a natural behavior. This is probably designed for smoother shifts. Maybe someone knows.

 

[POWERED by HONDA]

Originally posted by Bobby C 01TA:
I drive my buddies 98 around alot but have noticed that during fast shifts, the rpms jump while going through the gears.. He said something about a recall on the ECU that hasnt been done yet.. would this be causing the problem? Thanks!

I have a 98 as well that had to have the ECU replaced.

You'd only feel the surge if you let off the gas (even slightly) above 5000 rpm. If you shift properly, you won't feel the surge.

The "surge" is pretty hard. It feels like the fuel cuts-off.

[This message has been edited by POWERED by HONDA (edited 23 October 2002).]

 

[Bobby C 01TA]

usually during "normal" shifts it doesnt surge.. just during quick shifts do the rpms surge while going through gears.. the car only has 16k miles on it and I dont think the clutch has ever been replaced and it doesnt slip at all during stop and go traffic and always grabs when needed..and yes I am letting off the clucth completely when i shift LOL..like on the MR2 and friends 92 NSX.. there is no rpm surge during shifts.. hmmm.. i'll look into it.. thanks guys!

 

[NSX2NV]

Does anyone know if the 97's needed to have the ECU's replaced. I'haven't really noticed this problem, just curious about any recalls on my model year.

 

[ck]

http://www.nsxprime.com/FAQ/Reference/tsb/98-026.htm

?

It may be just that you are not used to the drive by wire system. Since its your friends car, ask him if he thinks somethings wrong. The newer cars drive differently and I noticed as well that the revs shoot up slightly between shifts. It is normal and you can control it depending on how you gas and shift. It actually helps match revs better, imo.

 

[5inchfatlip]

Just watch your foot work, you are most likely a bit on the gas while shifting through the neutral gate the shifter will get to the neutral gate without the clutch fully despressed. When going at high rpm one tends to forget and not be as precise as when cruising through the gears. It happens to me all the time.

I dont know about the ECU's, but I think it could be timing.

 

[Larry Bastanza]

Hey Guys,

I do not have an answer to this, but reading this thread and looking at the TSB we are talking about 2 opposite things here.

1. Rev's rising for some reason when the engine is uploaded (seems to be a DBW characteristic)

2. rev dropping prematurely, or too low, which is what the TSB relates to.

I have heard on this board before about the drive by wire cars having a little rpm rise upon release of the throttle.

Just wanted to make sure we are all discussing the same symptom.

LarryB

 

[Bobby C 01TA]

well I shift alot smoother and faster than my friend that has the car cause he hasnt had it but maybe 2 mos if that and its not driven much.. much less him just getting the hang of manual trannies..in short.. he didnt have much experience with manuals and he's still learning lol.. it could be that I'm shifting pretty fast with the accelerator slighty down.. i'll drive it soon again and see if thats it..btw.. what was the ecu recall for anyways?? and what happens if the problem isnt taken care of?

 

[Larry Bastanza]

Bobby,

See #2 above. Also a few threads up is a link to the actual TSB.

As far as what happens: the revs drop possible almost to a stall condition. I guess some cars could actually stall. I do not think it is earth shattering.

HTH,
LarryB

[This message has been edited by Larry Bastanza (edited 23 October 2002).]

 

[Bobby C 01TA]

cool thanks larry! The car definitely idles fine and smooth but i'll check the thread anyways.. he has yet to get it fixed.

 

[4AU4LIFE]

Drive by wire might be acting up.

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92 RED/BLACK 5-SPEED