So, I bought new tpms sensors for my 99 when I bought wheels. The car is reading my tire pressure for all 4 tires as 5-6 psi lower than what they actually are according to a handheld gauge.

I’ve tried re-pairing sensors with the car, and I’ve tried airing them up to ~44 psi and driving around to see if they’ll adjust.

Something I read mentioned the 97-00 sensors/pcm had some kind of correction for altitude. Is that true? If so is there some kind of pcm change I could make to fix it?

If the sensors are just bad, then i’d rather not replace them. Is there some way to get the car to un-recognize the sensors so that I don’t have to deal with the low pressure warnings?

 

I have a 2000 convertible. Don't know if the '97-'00 TPMS sensors adjust/compensate for altitude, or not. However, I'm curious as to the quality of tire gauge you're using. I have a good quality unit I've had for many years, and it's usually about 1 or 2lbs less than the TPMS sensors indicate. I've tried several brands of gauges, and a LOT of them are pretty bad. My way of doing it is to buy 2 of the exact same gauge, then test them to see if they read the same. If they're within a pound, great. Then I compare their readings to the TPMS readings. If they read within 1-2 pounds, I take one back and keep the other. Wish I could remember the brand name. The gauge also has a replaceable battery. BTW, my C5 STILL has the original TPMS sensors and batteries, now 20 years old!!!!

 

Another vote for try a different gage with a fresh battery.

 

Thanks guys, it appears I overlooked the obvious. Probably should have been the first thing to check. I noticed my tires were wearing a little more in the center than the edges so I assumed the gauge was right. Borrowed a better gauge and it matched perfectly with what the car is reading.

Will buy a new gauge to double check and keep an eye on the tread wear.

 

I've been following the TPMS discussions on the forum with a vested interest. When we picked up our 2000 Coupe the low tire pressure warning was displayed on the ride home. So we stopped at the first service station we found and filled the (right rear) tire. All set, right?
Get in the car the next day and drive about 200 yards up the street and get the low tire pressure warning - for the left front tire. So I checked the TPMS readouts and all the tires are reading low. (Oh, please don't tell me we have tire issues on a car we just picked up!)
I decided that the first order of business was to get a valid baseline. I let the car sit overnight in the garage. Then - with cold tires - I set the tire pressure to the recommended 30 psi.
We took the car for a ride and just about the same 200 yards up the road the DIC informs me I have a flat right rear tire. No way. I just checked the pressure before we left.
By the time we reached the end of the street, the message had cleared.
Since then we intermittently get the flat right rear tire message that clears once the tire warms and the right rear always reads 3-4 pounds low.
Not enough of a problem to invest money in. We'll live with it until we need new tires or the TPMS caps out completely.
If you're having a similar experience, I suggest you start with a baseline and drive the car several times before jumping into repairs or replacement.

 

I totally agree with you.

 

Lowcountry,

I have a 99 also. Mind asking what brand and model number of sensors you installed since they seem to be working with yours?

 

Schrader 28006 works quite well and are resonably priced. My .002

 

I just put a set of Schrader 28006's on my 2000 and worked like a charm. Used the magnet to program them. Very easy. RockAuto had the best price

 

Schrader 28006. Bought from rock auto. They had the best price at the time, I imagine they still do

 

It IS possible someone used the Fix-A-Flat spraycan to spray goop into the tire to limp home or somewhere to get the tire repaired. This can, and will work its way into the sensors, thereby preventing them from reading pressure.......

 

I looked everywhere locally, chain auto stores and online. The prices were stupid for my 98.

I was about to go with Schrader when I found tpms24/7.com. I paid $25 each and they have been flawless for almost 2 years. Great customer service too.

 

I answered in another thread too but the schrader 28006 was my fix too after a failed attempt at the cheapie set off ebay.