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When to be concerned about passing inspection with a small exhaust leak?

Just thought I’d ask what experience others have had with an exhaust leak and getting your vehicle to pass inspection. I tend to worry about it every year in MA for my 15+ year old Tundra, but it rarely seems to come up during inspection as an issue even when they’ve heard it over the last couple of years but never said anything. (1/4" hole in pipe next to CAT converter).

Only once has a potential leak come up and that was for a faulty muffler baffle which was recognized by another gas station inspection and passed. I’ve since replaced the muffler and resonator but not the pipes that lead to the CATs.

Guess I’m just concerned when I replace the pipes the least path of resistance for any leak will now be the exhaust manifold which is a $1500-$2000 repair (both sides) and I was last told that it MIGHT be leaking, but that was never confirmed.

What state? Every state has different inspection requirements.

That said, oftentimes they don’t care about post-cat leaks because that isn’t going to pollute any more than if the leak weren’t there. Anything post cat is just annoying from a noise perspective.

Massachusetts. So unless they smell exhaust or it gets too loud, it’s probably nothing to worry about?

Looks like your state wants the exhaust to be solid all the way back. Fix it.

Sounds like I’ve just been getting lucky for the past couple of years. I’m surprised they tend to be lax on it when they’re strict on every other little thing.

Sometimes it depends on the individual inspector. There’s no real way for the state to make the inspector care about the inspection, and if you get one who doesn’t he might just pencil-whip everything that isn’t checked by a machine.

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There are a lot of cars running around MA that shouldn’t have passed the emissions and safety inspections. The state can and will punish test technicians and facilities that knowingly circumvent the criteria if they have evidence to that effect. Some of these garages exist on the revenue from inspections and if they lose their certification, it’s a big deal. A place near where I used to live, notorious for passing just about anybody, was shut down by the state…

While I wouldn’t worry about a leak from a testing/certification perspective, it’s never good to have a hole underneath your car where the exhaust gases can get into the cabin area.

I just wished they gave people a small grace period (2 weeks perhaps??) to fix minor safety violations that don’t immediately endanger the driver, passenger or others on the road but I’m guessing due the complexity in qualifying that, it’s no real possibility.

A muffler shop might could weld that up for cheap.


No, the pipe is paper thin near the CAT. I really should’ve replaced the whole CAT back but just did the muffler and resonator not thinking the mid pipes would be worn out. Live and learn.

It depends on who does the testing. Most of the time you’ll just get an R sticker and have 30 days to fix it.

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Forget about inspections, I’d fix an exhaust leak like this one because I value my life and I don’t want to asphyxiate myself.


I wish that was the case (from the document @shadowfax posted):

4.07 (3)(a)

“A certificate of Rejection authorizes the operation of a motor vehicle for a period of 60 calendar days after inspection, 20 days for motorcycles, provided that all safety related equipment defect(s) have been corrected prior to continued operation. Safety related equipment defects are items of inspection exclusive of emissions inspection items.”

@Whitey It’s a very small leak. Nothing that would get into the cab area. It’s been like this for the past year. The prior leak just required a new O-ring gasket between exhaust sections.