91 NSX - TCS Problems

[JohnnyV]

I recently purchased my first NSX (1991, automatic, 50,500 miles). The battery was near dead when I went to collect the car so I jumped it using the recommended jump connection points. After the jump, the TCS started to activate under normal acceleration. I restarted the car in hopes to reset the computer, but that didn't help. When I manually turned off TCS, the car seemed to drive normally. I fear I damaged the sensors or wiring during the jump. I plan to have the code read but don't know who in Northern or Central California to bring it to for repairs. Please make recommendations. Thanks. - John

(Additional info) As I read through more posts I ran across this thread - http://www.nsxprime.com/forum/showthread.php/26690-Tire-size-to-prevent-TCS-problems regarding tire sizing and TCS activation. Once I got the car started I drove off to put a set of Bridgestone Potenza s-04 215/45 17s on the front and 285/30 18s on the rear. Any advice on tire size and TCS sensor activation? Thanks - John

 

[SW2 Heritage Cars]

Yes, it will be a tire size issue. The rotating circumference of the tires needs to match what comes on the car originally. Someone can correct me if I'm wrong, but the simplest way (and maybe only way) to solve this issue is to turn off the TCS when driving the car, or go back to stock circumference tires.

 

[Sportsmind4me]

Is there a reason you want to go with this tire size or are you just trying to replace the tires in that size because that's what it had on it when you purchased it? IMO, 285's are too wide unless the car is boosted or you have a really wide rear wheel. I'm running 215/40/17 front and 265/35/18 rear (which is the most common) with no TCS issues. I've read that some people have gotten by with 225/35/17 up front but experience rubbing when the wheel is at full lock. Hopefully this link will provide you with the answers you need: https://www.nsxprime.com/FAQ/TireWheel/wheeltech.htm

 

[Larry Bastanza]

It is not so much using the exact tire size, but you must match the diameter ratio between the front/rear, so the TCS does not interpret the tires as slipping. I know there have been a ton of posts here in prime about this over the years discussing tire sizes and changes that have the match ratios equal to stock.

Search "TCS" or "Traction Control"/ "Tire Sizes".......

 

[mwagner10702]

Your 285/30-18 is all wrong for the rear. The front / rear ratios are as follows:

91-93 = 1.079
94-01 = 1.046
02-05 = 1.054

With your 30 series rear tire you are probably out of bounds relative to the 1.079 ratio for a 1991. That's why your TCS is acting up. You should return them to the tire store and get a pair of 265/35-18 or 275/35-18.

When you find someone to read the codes you can reference this link for the code results. Keep in mind the 1991 NSX uses an older OBDI protocol and is not compatible with the newer OBDII readers. I mention this in case you are thinking of going to Autozone and borrowing an OBD reader. You can make your own jumper in order to read the codes.

https://www.nsxprime.com/wiki/Trouble_Codes

 

[JohnnyV]

Thank you all. These responses give me a lot to think about. I wish now that I had done more research before making the tire purchase. In my haste to take possession of the vehicle I may have shot myself in the foot.

 

[JohnnyV]

The ratios are very helpful. After the fact I searched for them but was unable to find a reference. Also, the Trouble Codes list will undoubtedly come in handy at some point. Thanks!

 

[JohnnyV]

Thanks Sportsmind4me, I was attempting to replace what was on the car. Original setup wat 215/40-17 up front and 285/30 rear. Now that I've seen the ratio data that others have posted I understand my error. The 215/45-17s I put up front are beyond the limits set by Honda. So I'm going back to the tire shop for an exchange. (Having never purchased tires for aftermarket wheels of a different dimension than the OEM wheels before I have not had trouble with diameter ratios in the past.) The link you provided was extremely helpful!

 

[mwagner10702]

Most people who run the 17/18 setup run the following:

Front: 215/40-17
Rear: 265/35-18

Slightly more aggressive is:

Front: 225/40-17
Rear: 275/35-18

Any wider in the front (i.e. 235) and you will rub the fender liner. The 275's in the rear may require a more aggressive alignment to prevent rubbing. If I were you I'd stick with 215/40-17 and 265/35-18. No way would I run 30 series 18's in the rear.

 

[JohnnyV]

I haven't made time to return to this thread. I ended up swapping the oversized Bridgstones for a Yokohama S-Drives:

215/40 17 front
275/35 18 rear.

Aside from relieving the TCS issue, these tires perform better (IMO) and they're quieter than the Bridgstones. This swap was a win-win as the set of Yokos were $300 less than the Bridgstones.

Thanks again for the advise.