I think I got hoodooed at Discount Tire.

While they were nice, they said my TPMS had to be "rebuilt". They did this for free, so I did not complain.

My first question is what the heck do they do when they rebuild your TPMS?

Next, they came out and had screwed up one of my TPMS sensors when they were trying to unscrew it out, claiming it was "crossthreaded from the factory". I kind of call BS on this, but maybe its a possibility.

The tech was able to re-tighten it, butyou can see a stretch mark in the plastic, so it if will hold up or not, I am unsure.

They said they can order me a new sensor, $61, but these sensors on my car have Mitsubishi stamped on them.

Obviously, they have what is required to flash my sensor to my car, which I would want, since I don't want to take the car to the dealer as it is 45 miles from my house, and I have no need for them to see my mods anyway.

Talking to Dino and the dude at Discount Tire, apparently there is a wireless module they use to activate or "wake up" the sensors, but they have to flash any new sensor through the OBD2 port.

Pardon my stupidity, but what are they accessing? And this is nothing I can access with my Tactrix cable, correct? I assume they access a different system and are never anywhere near my ROM, right?

Should I just drive the car and wait to see if I get a TPMS light? Or go ahead and pay $61 to order a sensor?

FWIW, to help the rest of you, I would not let anyone "rebuild your TPMS sensors", especially on a car with 9600 miles.

Thanks for any info. I know its 4 year old technology, and I haven't messed with it yet.

 

Re: sensor cross threaded from the factory.

While I haven't personally messed with the TPMS sensors, I can tell you that many of the evo x rear O2 sensors were cross threaded from the factory, so hearing it about a TPMS is not a stretch.

AFAIK, unless all four sensors play nice, you're going to get an annoying message on your LCD display.

As far as "rebuilding" your TPMS, it sounds suspect.

 

Discount tire employees are suspect. I've had many experience with them that are all horrible. They talk and act like they know what they are talking about and think that you don't know anything. If you call them out on something they back peddle, be really nice, and try and side track you with things like "oh we'll do this for free or take care of this and that". Hope it all works out for you man.

 

Just got my tires done last month. Discount tire sold me new TMPS sensors (mistake kinda)
They did there so called flash and told me to drive 50 miles and the Sensor light would go off.
(Didnt happen) So I had to take it to the dealership and have them redo sensor flash to get it to work. Know the shop manager there real well so no worries. I left my stock TPMS in stocker's and will mount them on snow tires for winter will just have to have the TPMS reflashed again. Kinda of a pain but not TPMS light.

 

Ganked from Club Lexus: "They install a kit. It has a new rubber seal (inside wheel - which is why it must be done with tire off) and the valve core. I guess the risk is that the seal may leak after time. I would think the valve core could be replaced at any time. I think I may skip it this time unless someone really knowledgeable chimes in. If it ain't broken..."

 

Ugh, I don't like this at all.

 

The "rebuild" consists of removing the TPMS valve core to let the air out (which is specific to the TPMS and NOT the same as a normal valve stem), then removing the TPMS retaining nut and washer thus letting the TPMS thingie drop into the tire. They do this cause the possibility of damaging a TPMS sensor while removing the tire is very high, like > 50%.

Then on re-assembly they use a "kit" that consists of a new viton seal on the inside of the TPMS stem into the hole in the wheel, a new seal and washer on the outside, a new nut, a new valve core and a new gray cap.

Some places charge 5-10 bucks for the "kit" and some places add 5 bucks labor for wheels that have TPMS devices installed versus a normal valve stem. it is lots more work for the tire changer.

Do a gooooogle search on "tpms rebuild kit".

 

Yup, this.

I worked at Goodyear & Firestone and yeah it does take an extra 5 min max per sensor. They "program" the TPMS by putting a scanner up to each valve (with the wheel/tire mounted on the car) for a few seconds until the scanner reads it and it's suppose to sync all 4 sensors together. It's a generic TPMS tool and it didn't seem to reset the higher end cars. So with some cars, we had to send them to the dealer.

TPMS sensors are usually a dealer item so idk about them costing 60 bucks... I've never seen them that cheap. And as far as cross-threaded, that's a technician issue. It's thin metal/threads and you can feel it starting to cross, so it takes some force (stupidity) to strip it. I hope you get this taken care of.

Edit: TPMS rebuilds were required to be done, store policy...

 

Sensor hex nuts come cross threaded from the factory on a lot of vehicles. I remember I worked on a Nissan Sentra with ALL 4 hex nuts cross threaded. No other way around except to purchase new sensors.

I'm pretty sure I posted this before somewhere but service packs (hex nut, core, grommet, etc) are about 2 bucks each and sensors are less than 60 bucks each at Costco.

I wish Mitsubishi chose the way Honda decided to use TPMS, by seperating the sensor with plastic/metal valvestem as seen here. If you screw up the valvestem, it's much cheaper to just replace the stem.

 

as mentioned before, a "rebuild" is just replacing parts that can be prone to leaking ie rubber seals. A new valve core is also put in and a new hex nut is put on. This is supposed to be done every you take apart a wheel with a sensor. However, sometimes the "kits" aren't currently available so they remain untouched.

Leaving the sensor in when changing tires only raises the risk of breaking it if the tech is not thinking. It is easy to change the tire with the sensor still installed, it's done many times.

 

Thanks everyone!