Compression Issues?

[Big Brown]

First off I would like to thank everyone for sharing their experiences as it has helped he gain more info about my NSX. I purchased a yellow 97 NSX in Las Vegas a few months back. I have always wanted one but never had the opportunity to purchase one nor found one for sale in my local area. When i saw this NSX on ebay in Las Vegas, i knew i had to have it and bought it a few days later. However, when going thru the threads i noticed the car i bought had some compression issues. Ok so now my questions....

1. This car is a weekend vehicle and i do not race nor push it to its limits. Would a weak cylinder affect anything if i am just driving it under normal conditions?

2. What should i do to fix it or should i just leave it since its not really noticeable. I never knew of the weak cylinder until reading the forums on this site.

3. Is it expensive to fix? what are the pros and cons of having a weak cylinder?


I would apprecaiate any suggestions as i know this site is great for anything pertaining to NSX's. Thanks in advance

Joe

 

[NSXclear]

You should probe further to see why you are getting a low compression in that one cylinder. Do a leak down test on it. Try to figure where the noise is coming from. Exhaust, intake, oil cap, oil dipstick, heads, coolant bottle, etc.

You can also try to put a teaspoon of motor oil in that cylinder to see if the conmpression improves. If it does, then it means your rings and/or cylinder are worn. No change usually means bad exhaust valve.

 

[theman1990]

Also, what do you consider to be "a weak cylinder"? What were the numbers?

 

[NSXclear]

Any cylinder that is more than 15% lower than the other cylinders. The normal compression usually falls around 170-210. You might get one cylinder that is significantly low, i.e. 60. That would be a weak cylinder.

 

[mystican]

take it factor x in las vegas .... they are very good...

 

[Big Brown]

i found an old post by vegasspeed who took the car to factor x and mikey was not concerned. the results shows it was 190 across the board except the first or last cylinder had a 160. I am going to take the car to hondoctors here in vegas to get a second opinion. I'll be sure to give you all an update. i never noticed anything about the car until i found it here in a post.

 

[VegasSpeed]

Sorry for the late response. I don't visit here as often as I used to. The car should be okay. I had different opinions on it. It is just like a doctor diagnosis. They give there best opinion but it could be wrong. Mike and I are friends so if you want a good NSX guy to look at the car he is the best. He took care of my BMW when I wanted the downpipes swapped as well. He can do almost any work on any car between him and his crew. NSX's are his specialty though. They do time attack cars out of an NSX for their job.

He said I should go give it hard run and go through the gears and warm it up. Then go and do a compression test after that. If test still comes out low than it might be an issue with a valve seal or a few other things. Chances are it is something simple like carbon build up in the first cylinder.

Call me up so I can at least take a look at the car again. I have seen it in a year or so. I was damn close to buying it. Truth be told I would have rebuilt the engine by now and put an FX500 kit on the car. I would be shocked if I didn't do it by now.

Honestly, if I have any car questions or concerns I call my BMW guy and I call Mike Angel. One of the two will have the right answer all the time.

BTW, I did finally dyno my BMW. It had pretty good numbers I thought