each time tire temperature readings are 28.9lbs or lower? My tire analog gauge consistently read 4lbs higher than the TPS. Meanwhile, my Nissan Tech says that his reads 4~5lbs higher on all TPS equipped cars from Nissan. I worry about having overinflated tires, particularly during winter months when I rather have softer tire pressure for more grip.

 

Mine are pretty dead on. Maybe you should get a new monitoring system under warranty.

 

We also thought that the monitoring system may be the culprit(improperly calibrated). However the Tech has commented that a number of local Zs have similar issues. What is disturbing is that he says they are having the same problem on their Maximas, etc. as well.

 

Couldv'e been a bad production run for whoever manufactures the TPS system. Happens a lot in manufacturing. A spec gets a little out of calibration and until it is caught, everything produced is flawed. Good luck.

 

I would think that since running over inflated tires can be a serious safety hazard, your dealer would replace them. I always use a regular pressure gauge when I check my pressures. The TPS system is more of a low pressure warning system for me. Keep us posted.

 

I was hoping someone else here had experienced something similar.

 

Hmm, my TPS sensors are very close to my analog gauge (maybe they are both equally wrong though). But this is also at pressures of 30-47 PSI (I've not been out of that range yet). Does your problem completely disappear @ higher pressures, or is it simply reduced? Sorry I don't have any more specific info.

However, I have the following two comments:

1. Lower pressures do not necessarily equal increased grip. The tire will often deform so that the contact patch is actually smaller than when properly inflated. The tire grip caused by deformation is on a very small scale (at least compared to the ability of the overall tire to conform to shapes) and is therefore governed mostly by the hardness (durometer) of the rubber, and not the pressure of the tire. Unless you are rock crawling, you would want to inflate the tires so that the contact patch is maximized.

2. Overinflation will depend on tire, but will need to be a large amount to cause problems. My OEM RE040's were running @ 47 PSI hot at the end of my first track day before I had a chance to bleed them down to 42 PSI.

So, I'd say that it sounds like you may have an issue with the TPS, but I'd also say that you should put some more air in the tire.

Good luck!

-D'oh!

 

Your information is very correct. At colder outside temperatures I prefer the tires to be 29~30lbs. As the tire begins to warm, tire pressure tends to increase only a couple of pounds. This still gives me a comfortable ride without sacrificing traction and without jarring any of my fillings out of my teeth.

I am inclined to agree with you, especially considering the lack of response from others regarding this issue.

 

My TPS always reads about 2-3 pounds lower than my analog gauges. I have used three different quality air gauges and they all agree..........so I would have to conclude that my TPS system is off.

 

I find it curious that the TPS would be calibrated to read lower than it actually is. Do you think that this is a result of all the recent litigation regarding under inflated tires? Wouldn't this more or less defeat the purpose of TPS if it is giving you inaccurate readings? If enough people complain, then perhaps Nissan will do soemthing about. I cannot imagine that this is isolated to only 350Z though. I would be interested to know whether other model Nissan owners are experiencing the same thing. Perhaps someone who is a regular at www.FreshAlloy.com could do a cursory check.