#ExhaustLeak

Numerous reports of an exhaust smell in the cabin of late-model Ford Explorers prompted the National Highway Traffic Safety Administration to open an investigation.

According to Reuters (via Automotive News), safety officials began looking into 2011–2015 Explorers last Friday after receiving 154 complaints of an exhaust odor. The issue, which is reported to be a factor in one crash (that didn’t result in injuries), persists in some vehicles even after they were repaired to correct the problem.

Joey writes:

Hello Sajeev,

I’ve been a reader of yours for years and greatly enjoy your style. (Woot! —SM)

My question is about my ’97 Mazda 626, with a hair over 215,000 miles on it, that’s been in my family for its entire life. It’s reliable, economical, and generally in good condition.

However, I am up for a registration renewal in October, and I need to complete an emissions test. I figured that it would be a good idea to check up on the codes behind the check engine light. The codes came up as an evaporative system and catalytic converter errors, which are both emissions fails.

Andrew writes:

Hi Sajeev,

I’m trying to wring a few more years out of my 1994 Geo Prizm, and recently the engine got louder. It’s a very low end bass like sound that makes the whole car vibrate a lot more.

The muffler and resonator are relatively new, and the noise seems localized to the front of the car. What’s odd is that the engine is the loudest when it’s idle. As soon as the RPMs go above 1500, the engine is only a little louder than it normally would be. How do I find out if the problem is the exhaust manifold, or the downpipe from the manifold to the catalytic converter? Over the summer there was a brief time when coolant was leaking and dripping down onto that downpipe and burning off. That leak issue was addressed, but that downpipe has some rusty sections on it anyway.

Sajeev answers:

I have a 2007 Hyundai Accent 5-speed manual hatch. When I’m driving, sometimes I’ll hear a little ‘psssht’ noise as I pass through 2500 rpm. It almost sounds like a tiny blowoff valve under the car.