Browse By

Driving with an EVAP System Leak – Is it Safe? is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to As an Amazon Associate this site earns from qualifying purchases.

We recently took an in-depth look at some of the best EVAP smoke machines on the market.

If you own one of these machines and use it to periodically check your vehicle for leaks, you could end up in a situation of knowing you have a problem but need to drive your vehicle before you can get it fixed.

Is this safe you may ask?

The answer is relatively simple; you and your car should come to no harm, however, you are causing more pollution and your vehicle will not pass any future tests while it is in its current conditions.

So while you may drive your car, the best course of action is to see the leak as soon as you can.

What about if I don’t have an EVAP smoke machine? How can I tell if there’s a leak?

The most obvious solution to this is to have your vehicle checked out with a service.

However, before you give your nearest auto-shop a call, there are some small troubleshooting tips you can carry out if you don’t have access to an EVAP smoke machine.

Symptoms that indicate a potential issue with the EVAP system:
  • The Check Engine Light may come on while you are driving, (this could be accompanied by a smell of fuel). If you have recently filled up the car, you should check that the gas cap has been fixed back into place properly.
  • If the cap is tight and you still have a check engine sign or can smell fuel, you could have a leak. This could come from all manner of areas within the EVAP system; faulty vent o-rings, and defective purge valves are a common source of leaks.
  • Remember, if you have a leak, it will be leaking emissions even when you are not driving. Do a smell test after your car has been parked for a while; if you still detect an aroma of fuel, your EVAP system may well be faulty.
  • If after these troubleshooting tips you suspect that your EVAP system has sprung a leak, it is time to call your mechanic. They will be able to find the source of the problem with an EVAP smoke machine. From there they will be able to fix it for you.

Essentially, EVAP system faults are common however they can be difficult to detect. Without the proper equipment, you will have problems ascertaining exactly where the issue stems from.

For that reason, you should not leave it too long before taking your car in for a diagnostics check-up.

While it is safe to drive a vehicle with an EVAP fault, you will be polluting the atmosphere so the sooner you fix it the better

Image Credits:

Leave a Reply