Not again...the car is being annoying....

[Auraraptor]

Great! I was all ready to take my baby down to Baltimore today with me, but then she is acting odd. Basicly I go to put in gas and notice she isnt driving right.

Here is the problem: Everytime I am coming to a stop and have the clutched pressed in, the tach falls to below idle speed...and keeps falling to near stall out speed...it even gives that "shudder" you get at too low rpms. Just as it is about to stall out, it saves itself again and goes to idle speed.

Other things: When I stoped the car (engine temp at normal) and put up the glass, the engine was making a hissing noise as if there is a leak, but I couldnt (still if any of you remember my last post) find it.

ps I still cant drive a manual very well

Help please!

I took it to my mech and he is as confused about it as I am.

------------------
Auraraptor

1999 Honda Prelude "Mina" (finally the daily)
1998 BMW 750iL "Katrina"
1997 NSX "Nina"
1982 BMW 633CSi "Jessica"

 

[TyraNSX]

Just a guess, but that hiss could be a vacuum leak which might explain your near stalling. Maybe you have aloose or cracked hose. Try homing in on the source of the noise.

 

[Auraraptor]

We tried (I did and so did my mechanic) But we cant pin point the leak.

 

[ANYTIME]

Get some carb. cleaner and spray around all the vacuum lines and gasket areas by the throttle body. If the car starts idleing faster, then you know where the leak and or cracked line is. Just a thought.
John

 

[Larry Bastanza]

I recall a discussion a while ago in which there was one vacuum line running under the strut bar. Many folks had changed the strut bar to an aftermarket bar and the line was rubbing and caused a vacuum leak after some time.

Do you have an OEM strut bar? I am grasping here.

I have to say the advise you have gotten from John (anytime) is right on. It does indeed sound like vacuum leak. You just have to find it.

If you hear a hissing, get a small 1/2 hose about 2' long. Play doctor!! One end in your ear the other nosing around under the hatch.

HTH,
LarryB

 

[Slingshot]

Originally posted by Auraraptor:
We tried (I did and so did my mechanic) But we cant pin point the leak.

Check the fast idle thermo valve and also the idle air control (IAC)valve on the intake manifold behind the throttle body (1993 Service Manual illustration 9-2)for possible leakage.

 

[docjohn]

If you do rule out a leak and you are left clueless you might want to check your o2 sensors on the cats and manifold, mine went bad and my car was behaving exactly as you describe,some folks also have this problem when using cat bipass pipes with obd2 cars.

 

[NSXTC]

I had the exact same problem you are describing, save the hissing sound, which could be a separate issue. For me, it was the main fuel relay. If you hear a clicking sound coming from right behind your head when you are about to stall out, this could be your culprit.

------------------
All My NSX'es Live in Texas

 

[sjs]

Good tip on the relay.

Other than that, it sure sounds like a vacuum leak. Start by checking vacuum at 700 rpm. If it's below 20 then a leak is probable. (but it could be 20+ and still have a leak) The carb cleaner trick usually works, but another approach is to start pinching off various vacuum lines near each end and listen for the hiss to go away. If that doesn't identify it then it could be something like the dash pot, intake gasket, or even a cracked casting. Patience is required, but a good ear and carb cleaner should do the trick eventually.

 

[Auraraptor]

Well, we are still working on the leak thing, but for some reason the near stalling went away....

here is an update:

The battery was dead just before the above mentioned drive...and was just recharged prior to the incident (now its like a law case

) It is still doing everything, but now is not nearly stalling out (it still goes sub ideal and rebounds, but not to near death w/ shudder).....

Also, a check of the onboard comp. shows that one of the O2 sensors is running really rich (but not enough to set of the check enigne light)

aside from above, everything is still 'freaky'

though the lack of the shuddering is nice

[This message has been edited by Auraraptor (edited 21 October 2002).]

 

[nsxxtreme]

Originally posted by ANYTIME:
Get some carb. cleaner and spray around all the vacuum lines and gasket areas by the throttle body. If the car starts idleing faster, then you know where the leak and or cracked line is. Just a thought.
John

This is the best advice to find a vacuum leak. I thought it was the other way around though, car should stall when you find the leak with carb cleaner. It's been a while since I have done this though.

 

[PHOEN$X]

Did you just have the timing belt serviced? If so, it could be off. That's what happened to mine, and I had nearly the same symptoms. Good luck.

 

[Auraraptor]

Originally posted by PHOEN$X:
Did you just have the timing belt serviced? If so, it could be off. That's what happened to mine, and I had nearly the same symptoms. Good luck.

hmm the car only has 29k miles on it....would i need it this early?

 

[Larry Bastanza]

What year is the car?

The service interval is 90K miles OR 6 years for he timing belt. So it is probably due.

HTH,
LarryB

 

[Auraraptor]

97

 

[Larry Bastanza]

Sounds like you have some time to go then.

No timing belt change required now.

HTH,
LarryB

 

[Auraraptor]

Any suggestions on price then for the vaccum leak fix? (estimate so I dont get over charged by Acura)?

thnks

 

[Larry Bastanza]

This is hard to estimate. Since this will be a troubleshooting job, I would think that a good NSX experienced tech should be able to pinpoint it in an hour. (Maybe I am under estimating here, but it could go both ways, a really good tech may open the hood and go, OK you need this!).

Then you will tack on any actual repair cost based on what they find.

Frankly, this is a very hard question to ask via the forum, since we cannot actually hear and define your problem.

HTH,
LarryB

 

[Auraraptor]

well thnks to all for your help!

 

[bugsbunny]

Originally posted by Auraraptor:
well thnks to all for your help!

Quick Note: Sourcing a problem sound. You or your mechanic should have a Stethoscope Probe and a electronic listener. These are the best for finding a specific sound location amoung collateral abient noise.

Dont concentrate just in hose-laden areas, could be elsewhere. Good luck