Can Fix-A-Flat Damage Tire Pressure Monitor Sensors?

Products like Fix-A-Flat get you back on the road quick and easy, but there can be complications with the TPMS.
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The relationship between Tire Pressure Monitoring System sensors and products like Fix-A-Flat is complicated. Conventional wisdom has said for a while that products like Fix-A-Flat and TPMS sensors don’t mix, but expert opinions have shifted in recent years.

This damage question assumes that the TPMS sensors in question are located inside the tire. Most OEM TPMS sensors are built into the valve stem, with the delicate sensor portion located inside the tire, but there are other systems where the sensor is in the cap. When a ​TMPS sensor is located in the cap, it can't be damaged by anything that's inside the tire.

Types of Emergency Tire Repair Products

Fix-A-Flat is a brand name that people tend to use in reference to all products in the same range, in the same way, that people will call generic tissue paper Kleenex, refer to a photocopy as a Xerox, or Google for information on the internet. That said, products like Fix-A-Flat, Slime, and other emergency tire sealers and inflators all work on the same general principle of injecting a sealant and then filling the tire with air or some other gas.

There are two types of these emergency tire repair products. The first contains both a sealant and some type of compressed gas, typically in a cannister. When this type of product is used, the tire is both sealed and inflated to some degree. The other type consists of a sealant in addition to an air pump. The sealant seals the leak from the inside out, and the pump is used to fill the tire to a safe level.

There are also two persistent rumors that surround these types of products. The first is that they can cause fires or explosions, and the other is that they can damage tires, rims, and TPMS sensors.

Combustible Tires

Fix-A-Flat is the type that combines a sealant and compressed gas into a single dispenser. At one point, the gas was combustible, which is where the rumor that Fix-A-Flat causes fires or explosions came from. The idea was that if an emergency tire repair product uses a flammable gas, and dispenses that flammable gas into a tire, it could catch on fire during the repair.

Since most tire repairs involve removing the foreign object that punctured the tire and then reaming out the hole with a special metal tool, the idea that the tool rubbing against the steel belts in the tire could create a spark, and ignite the flammable material left in the tire from an emergency Fix-A-Flat application was very real.

Today, Fix-A-Flat uses non-flammable materials, but the rumor persists, and it’s always possible that someone, somewhere, is still manufacturing an emergency tire product that uses a flammable propellant, or that someone still has an ancient can of old-stock Fix-A-Flat laying around that still works.

Damage to TPMS Sensors, Tires, and Rims

If you run an image search for rims or TPMS sensors that were damaged by Fix-A-Flat, get ready to view some tire gore. It’s unclear whether this type of damage is actually caused by modern Fix-A-Flat, by older versions, or by similar products in the same range. It’s also unclear as to how long it takes for this type of corrosion and other damage to occur.

For example, Fix-A-Flat claims that its product is safe for use with TPMS, but with the caveat that you should promptly fix, clean, and inspect the tire. So while the product as currently formulated is designed to be safe for use with TPMS sensors, driving around for an extended period of time without having the tire cleaned and fixed may have unforeseen consequences.

All emergency tire repair products leave some form of residue inside the tire that has to be cleaned out. This is a problem because most tire repairs that involve some type of puncture can be repaired either on the vehicle or at least without removing the tire from the rim. The typical procedure involves removing the foreign object, reaming out the hole with a specialty tool, and then installing a plug.

When you inject a product like Fix-A-Flat or Slime into your tire, the tire has to be removed from the rim, and cleaned, before it can be repaired. If the puncture is simply plugged, the sealant will remain in the tire. This can make difficult or impossible to balance a tire, and it can also render a TPMS sensor inoperable or inaccurate.

Cleaning Tires and TPMS Sensors After Using Fix-A-Flat

When you take a tire in for repairs after using a product like Fix-A-Flat or Slime, it’s important to let the shop know that you used one of these products.

Rather than simply plugging a damaged tire that was temporarily repaired with Fix-A-Flat, the manufacturers of Fix-A-Flat and other similar products recommend that the interior of the tire and rim be cleaned with water before any repairs take place. If the vehicle has a TPMS system, then it’s also important for the sensors to be cleaned at this time.

In most cases, cleaning a TPMS sensor before repairing and mounting the damaged tire will return it to useful service. In fact, Consumer Reports ran tests on a number of different types of emergency tire repair products and vehicles, and they found that none of these products damaged the TPMS sensors if the sensors were cleaned after the product was used.