Re: Rough Idle on Nsx.

[pok8rok8]

Re: Rough Idle on Nsx.

Hi all I just bought a 91 NSX today...and I went straight to my mechanic. He noticed the vibration on my car and said he thinks its a misfire caused by either sparkplugs, injectors or one other item that they replaced on the late model cars its called a cylinder crank sensor. Apparently this is located inside the valve cover on the firewall side facing the right of the car. This component is covered by a plastic / wax or something like that and at high temp it melts. I guess this was the problem but Im actually going to check the small ones first then if it doesnt work I will replace that. The part # if interested is37840-pr7-a02. Good luck to all who have this problem.....And WHOOOO hooooooooo I have one now.......

Mike

Ps. the part cost 253.09 CDN retail. and is always back ordered.

 

[pimp42]

Originally posted by pok8rok8:
Hi all I just bought a 91 NSX today...and I went straight to my mechanic. He noticed the vibration on my car and said he thinks its a misfire caused by either sparkplugs, injectors or one other item that they replaced on the late model cars its called a cylinder crank sensor. Apparently this is located inside the valve cover on the firewall side facing the right of the car. This component is covered by a plastic / wax or something like that and at high temp it melts. I guess this was the problem but Im actually going to check the small ones first then if it doesnt work I will replace that. The part # if interested is37840-pr7-a02. Good luck to all who have this problem.....And WHOOOO hooooooooo I have one now.......

Mike

Ps. the part cost 253.09 CDN retail. and is always back ordered.

You know that All NSX's have a rough idle around 1200 - 1500rpm, right?

 

[NSXaholic]

Originally posted by pok8rok8:
Hi all I just bought a 91 NSX today...

Congratulations pok8rok8!! I know the incredible smile you must have on your face right now!!

Originally posted by pok8rok8:
...I went straight to my mechanic...

Always a good idea after buying a car to get it completely checked up. Does "your mechanic" work at an authorized Acura dealer that employs trained NSX mechanics. Did you get a PPI (pre-purchase inspection) done before you bought the car??

Originally posted by pok8rok8:
...He noticed the vibration on my car and said he thinks its a misfire caused by either sparkplugs, injectors or one other item that they replaced on the late model cars its called a cylinder crank sensor.

It may well be this problem (I have never heard of this issue), but I would reiterate the need of making sure that the mechanic you are speaking with is well-versed in working on the NSX (and preferably is part of the service team of an authorized Acura dealer.)

Originally posted by pimp42:
You know that All NSX's have a rough idle around 1200 - 1500rpm, right?

Please tell me you're kidding right!! Mine is so smooth that often I can't tell that the car is on.

Regards.

 

[DanO]

Originally posted by pok8rok8:
He noticed the vibration on my car and said he thinks its a misfire caused by either sparkplugs, injectors or one other item that they replaced on the late model cars its called a cylinder crank sensor. Apparently this is located inside the valve cover...

Congratulations on the purchase of your new car!!! Awesome!!!

Lots of times a vibration may be the cause of an ignition coil. I’d start with the spark plugs and test the ignition coils at the same time—look at the service manual or www.danoland.com/nsxgarage for some details on this procedure. The injectors are a little more complicated to check and are rarely the cause of engine vibration with a stock NSX.

I have heard of the crank/cylinder position sensor going bad on some (a very few NSXes). As you said, the sensor is located in the passenger side of the front head behind the timing belt and cam gears. The removal/replacement of this sensor is no easy task as it requires the removal of the timing belt and cam pulleys (see SM page 6-27). This is no easy task and is better left to an NSX pro.

As Pimp42 says above, there is a certain amount of engine vibration expected with V-6 engines in the 1,200 – 1,500 RPM range.

Good luck with your diagnosis and keep us informed!

DanO

[This message has been edited by DanO (edited 15 February 2003).]

 

[pimp42]

NSXaholic: What kind of wheels are those?

 

[NSXaholic]

Originally posted by pimp42:
NSXaholic: What kind of wheels are those?

SSR Integrals. Love 'em. More pics here.

Regards.

 

[ncdogdoc]

Originally posted by NSXaholic:
Please tell me you're kidding right!! Mine is so smooth that often I can't tell that the car is on.

Well, your engine assembler must have been on the mark that morning. I have two NSXes and both have a mild but noticeable vibration at idle. Never bothers me because they both run like the wind

------------------
Gary Yates
1995 Red/Tan Boooleevard Cruzer
1992 White/Black Track Rat
2002 Red and White Cooper S - for sale, please inquire

 

[pok8rok8]

Hey guys thanks for the support.....I really have this smile and its not coming off.....My experience is damn right awesome. Thank god I did not listen to my friends who advised me to just buy a new s2000 or supra. instead I bought an old car that was worth buying. My only concern is that....its not on idle but when i accelerate from 1000- about 1800 the car seems to shake or sorry vibrate. I thought maybe its my inexperience on the car but I put it on neutral and revd it up to that area of question and still it did that. I guess I'll find out if its really a spark plug or something. Do you guys think its anything like a bent valve? Do you know what would happen if I had that problem?

Mike

[This message has been edited by pok8rok8 (edited 15 February 2003).]

 

[madfast]

ask your mechanic to check on the engine mounts

 

[pok8rok8]

Originally posted by madfast:
ask your mechanic to check on the engine mounts

Is that a typical or a common occurance with these cars??

Mike

 

[DanO]

Originally posted by pok8rok8:
Do you guys think its anything like a bent valve? Do you know what would happen if I had that problem?

Most likely it would sputter through the whole RPM band. When your mechanic pulls the plugs he’ll be able to tell by looking at them if something is wrong with a cylinder. If you really want to know, then have him do a compression and leak down test while the plugs are out.

DanO


[This message has been edited by DanO (edited 16 February 2003).]

 

[ScienceofSpeed]

Congrats on your purchase. The black potting material is ok, they all do it (even the late models). The potting material encases the crank position sensor, however, it is already rigidly mounted in it's shell, so the material melting does not cause any problems. Every engine I've seen as it. I'm not sure I would buy a new one based on this diagnosis. I would check your basic fuel/spark tune-up items and check your engine mounts. The NSX motor has a given resonance it creates in the low RPM that may be amplified by your engine mounts being worn.

Peace,
-- Chris

------------------
Revolutionize your NSX with ScienceofSpeed
www.ScienceofSpeed.com | [email protected] | 877-863-4520

 

[pok8rok8]

Originally posted by ScienceofSpeed:
The NSX motor has a given resonance it creates in the low RPM that may be amplified by your engine mounts being worn.

Peace,
-- Chris

[/B]

any new engine mounts available out there that wont wear or is this normal...

Mike

 

[I Grok NSX]

My NSX's rough idle disappeared when the headers were installed.

------------------
1994 Green-black roof/tan, 5 speed
Do you know of another Green-Black roof NSX?? Please email me if you do.

 

[matteni]

Originally posted by Litesokneecough:
My NSX's rough idle disappeared when the headers were installed.

Probably cause your lower engine mount was loose. The oposite happened to me and once I tightened it up - got better

 

[pimp42]

Originally posted by ScienceofSpeed:
Congrats on your purchase. The black potting material is ok, they all do it (even the late models). The potting material encases the crank position sensor, however, it is already rigidly mounted in it's shell, so the material melting does not cause any problems. Every engine I've seen as it. I'm not sure I would buy a new one based on this diagnosis. I would check your basic fuel/spark tune-up items and check your engine mounts. The NSX motor has a given resonance it creates in the low RPM that may be amplified by your engine mounts being worn.

Peace,
-- Chris

Chris - Do you guys sell any poly mounts or anything stiffer than stock?

 

[Fun2romein]

I have a 2000 that has a rough/miss from time to time at low idle. Took it to the Acura dealer and I was told nothing wrong. I have a hard time believing this. The NSX specialist was not there the day I had the oil changed so I will be taking it back. Furthermore, I have 2nd gear lock-out occasionally and will get a bit of grind if not ultra careful in shifting. Does anyone have any thoughts on this issues?

 

[nsx_parts]

I have a six speed out of a 2k in my 91 and had the same kind of shifting problems when the car was cold. I replaced the tranny lube with Redline and it shifts PERFECT now.

When was the last time the fluid was changed? How many ticks on the odo?



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Please visit http://www.nsxparts.com. The best place to buy and sell parts for your NSX.

 

[Fun2romein]

nsxparts.com I assume your questions are addressed to me "Fun2romein". I can tell you that it has had the recommended scheduled maintenance and just serviced at 10k 2 weeks ago. One would think that if a customer asked to look into a problem the technician would advise properly. I got a simple reply that they found no problem. Should I be telling them what to do or what to look for?