Exhaust and fuel are covered in Section 1 of Ontario's inspection standard, and both are treated seriously for the same reason: one can put carbon monoxide into the cabin, and the other can put gasoline onto a hot surface.
That said, the standard is more reasonable here than people expect. Some conditions everyone assumes are failures are explicitly described as normal.
What fails on the exhaust
The manifold fails if broken, cracked, leaking, loose or missing.
The muffler fails if:
- Cracked, perforated or leaking
- Bypassed, disabled, missing or removed
- A deficient part is used that does not meet OEM standard
- Patched in a way inconsistent with industry standard
The standard notes plainly that the OEM muffler, or one meeting OEM standard, is required on every vehicle. Straight-piping fails.
Resonator, catalytic converter and particulate trap fail if cracked, perforated or leaking, or patched in a way inconsistent with industry standard.
Exhaust pipe fails if cracked, collapsed or pinched, missing, perforated or leaking, or improperly patched.
Mounting hardware fails if broken, insecure, loose or missing, or if a deficient part not meeting OEM standard is used. Broken hangers are one of the most common exhaust failures on Ottawa vehicles — road salt eats them, and once one lets go the rest carry a load they were not designed for.
Turbocharger fails if leaking exhaust gases, or with a level 3 leak of oil or coolant.
What the standard says is normal
Here is the part worth knowing: "Minor leaking and resulting soot tracks are normal at joints in exhaust systems."
That sentence is in the standard. Light soot staining at a joint is not a failure. Surface rust on an exhaust is not a failure either.
What fails is an actual crack, perforation or leak in a component — a different thing from staining at a slip joint.
Where the exhaust exits
Several specific rules here, and they catch modified vehicles:
- Exhaust gases expelled into the occupant compartment fails
- Exhaust gases expelled within the perimeter of the cab fails
- An exhaust system shortened or modified so it fails to direct exhaust beyond the underbody of the occupant or luggage compartment fails
- The distance between the outlet and the periphery of the underbody, past which it directs the exhaust, must not exceed 15 cm
- Any exhaust component passing through an occupant compartment fails
Heat damage
The vehicle fails if an exhaust component is located so as to cause charring or other heat damage to any wiring, fuel line, brake line or combustible material.
The standard adds a useful note: heat damage can sometimes result from a missing heat shield that the manufacturer originally provided. Heat shields rust off constantly in Ottawa, and while a rattling shield is an annoyance, a missing one that has let something char is a genuine failure.
Fuel system: any visible leak fails
The fuel system has the strictest leak rule in the entire standard.
The vehicle fails for a level 1 leak or spillage of fuel present from any part of the fuel system. Level 1 is the mildest category — seepage not even great enough to form drops. For brake fluid the threshold is the same; for most other systems it is level 2 or 3. For fuel, any evidence at all fails.
Other fuel system failures:
- Filler cap of an improper type, or missing
- Tank, filler neck or vent tube cracked, perforated, insecurely mounted, or with a broken weld
- An improper tank not intended for automotive fuel storage
- An improper vent, or an improper repair
- Tank mount and strap broken, cracked, loose or missing, or a deficient part not meeting OEM standard
- Lines, hoses, fittings and connections chafed, cracked or insecure, or any section worn or damaged
- A product used that is not approved for fuel system use
- Fuel pump damaged or insecure
The fuel tank level must be recorded on your inspection report — one of the standard's listed recordable items.
LPG, CNG and propane conversions
Vehicles converted to run on pressurized or liquefied fuel have an additional layer. In Ontario, pressurized fuel systems are inspected under the Technical Standards and Safety Act and administered by the TSSA — the safety inspection items are a general check and do not replace the TSSA requirements.
For the safety inspection specifically, the vehicle fails if:
- A required TSSA compliance decal is not displayed, is incorrect, is unreadable, or the window label is expired (2 decals required for CNG-converted vehicles, 3 for LPG-converted)
- The propane or natural gas diamond label is missing — a weather-resistant, diamond-shaped label affixed to the exterior lower-right rear surface, but not to the bumper
- The tank or cylinder is cracked or damaged, or improperly repaired
- Tank mounts, straps, lines, hoses, fittings or connections are damaged or insecure
- There is evidence of any fuel leak
The standard also includes sensible advice: if you smell propane or natural gas, contact an authorized repair facility.
Drive belts — the useful exception
Engine and accessory drive belts fail if broken, frayed, oil-contaminated or missing, if a crack exceeds OEM or industry standard, if the belt is slipping, or if a pulley is bent, broken, cracked or out of alignment.
But there is a practical exception worth knowing: a drive belt that is not required for safe operation of the vehicle — the example the standard gives is air conditioning — may be missing if it does not affect the operation of required vehicle functions.
So a removed A/C belt is not automatically a failure. A cracked serpentine belt driving the power steering and alternator is.
Drive shafts and CV joints
U-joints and CV joints fail if rotational free play is present, if the joint is noisy during the road test while affecting wheel rotation or steering, if the protective boot is loose, missing, open, cracked or torn, or if lubricant is leaking from a CV joint.
Another sensible note here: weather checking or cracking on a boot is permissible as long as no crack exposes internal joint components or lubricant to contamination. A boot with fine surface cracks that is still sealed passes; a split boot slinging grease does not.
Hanger brackets and hardware fail if missing, loose or cracked, or mounted in a way that fails to prevent the drive shaft from falling to the ground.
Frequently asked questions
Will a small exhaust leak fail my safety inspection? A crack, perforation or leak in a component fails. But the standard explicitly treats minor leaking and the resulting soot tracks at exhaust joints as normal, so light staining at a slip joint is not a failure. If you can hear it from inside the car or it changes with engine speed, get it looked at.
Does a straight-piped or removed muffler fail? Yes. The standard requires the OEM muffler or one meeting OEM standard on every vehicle, and fails a muffler that is bypassed, disabled, missing or removed.
Will a missing heat shield fail my inspection? Not by itself. It fails if an exhaust component is positioned so as to cause charring or other heat damage to wiring, fuel lines, brake lines or combustible material — which a missing heat shield can allow.
Is a rusty exhaust an automatic failure? No. Surface rust is not a failure. Perforation, cracking or leaking is, as are broken or missing hangers and mounting hardware.
Can I pass with the A/C belt removed? Generally yes. The standard permits a drive belt not required for safe operation — it names A/C as the example — to be missing, provided it does not affect required vehicle functions.
Does a missing gas cap fail a safety inspection? Yes. A filler cap that is missing or of an improper type is a listed failure.
Hearing something from underneath? Have it checked before your inspection. See our exhaust system repair service or call (613) 789-2128. Franco Garage, 70 Beech Street, Ottawa — a licensed Vehicle Inspection Centre.