Study: Jeep, Ram diesels emit up to 20 times the legal limit of pollutants

June 14, 2017

Remember West Virginia University’s Center for Alternative Fuels, Engines and Emissions (CAFEE), home to the team of researchers who first told the world that Volkswagen diesels were designed to cheat on emissions tests?

Well, they recently conducted similar tests on diesels from Fiat Chrysler Automobiles, and there are some striking similarities.

If you regularly follow auto news headlines, that may not be too surprising. By the end of 2016, FCA was the target of not one, but two lawsuits from diesel owners, who claimed that their Jeep and Ram vehicles emitted more pollutants than advertised.

In January of this year, the Environmental Protection Agency said that FCA diesels violated the U.S. Clean Air Act. Soon after, FCA's CEO, Sergio Marchionne, warned investors that the company could soon become embroiled in a Dieselgate scandal of its own. Within weeks, FCA vehicles were among those from several automakers being investigated for emissions fraud in Europe. 

A couple of months later, rumors began swirling that FCA would be sued by federal regulators here in the U.S. Those rumors recently proved to be true, and if the automaker is found guilty, it could face fines of up to $4.6 billion.

New findings

CAFEE researchers conducted both lab and on-road tests of Jeep Grand Cherokee and Ram 1500 diesels from the 2014 and 2015 model years. The team discovered that under real-world driving conditions, those vehicles emitted up to 20 times the legal limit of pollutants--specifically, nitrogen oxide, which can cause smog and acid rain, not to mention fatal health problems.

The researchers haven't gone so far as to accuse FCA of cheating. However, the discrepancies between the two sets of tests are significant, suggesting that they aren't simply accidental.

FCA disputes findings

Fiat Chrysler has several bones to pick with the CAFEE team. Among them:

1. FCA questions how the study was funded. The automaker claims that it was paid for by plaintiffs in the suits mentioned above. CAFEE hasn't commented on who funded the study.

2. FCA argues that there are no federal standards for on-road tests of diesel vehicles. As a result, FCA never had to design its vehicles to pass on-road tests, and so, the company argues, it's unfair to subject diesels to such tests now.

3. FCA argues that the on-road tests CAFEE conducted were more rigorous than federal tests. Among other things, FCA says that CAFEE tests were carried out at faster speeds, on steeper grades, and with heavier payloads than diesels would have had to endure in EPA labs. In a statement, FCA says that:

"Each of the above may increase emissions readings, therefore rendering invalid a comparison of on-road and off-road test results. Further, the aggregation of these variations makes any comparison misleading."

CAFEE director Daniel Carder responded to item number three by admitting that the tests were more rigorous than those conducted in labs. However, he pointed out that emissions ticked up significantly throughout the testing process, even in situations where increases wouldn't be expected. 

Our take

In our experience, where there's smoke, there's often fire.

That's not to suggest that FCA or its diesel partners, VM Motori and Cummins, intentionally designed engines to emit more nitrogen oxide than legally allowable. However, when a company is facing two lawsuits from consumers and is the subject of two governmental probes, it suggests that something is amiss. 

As far as this particular study is concerned, CAFEE has a fair degree of credibility, being the first to bring attention to Volkswagen's massive misdeeds. Was the study unduly influenced by the study's funders? It's possible, but it's also worth noting that CAFEE's accurate Volkswagen study was funded by the International Council on Clean Transportation, which is not agenda-free:

"The International Council on Clean Transportation is an independent nonprofit organization founded to provide first-rate, unbiased research and technical and scientific analysis to environmental regulators. Our mission is to improve the environmental performance and energy efficiency of road, marine, and air transportation, in order to benefit public health and mitigate climate change."

So yes, while it's often possible for funders to shape study findings, we didn't see that in CAFEE's previous study on diesel emissions. Whether it happened this go-round is worth investigating, but it's premature to throw out the study's findings simply because of the funding source. (We do wish, however, that Carder would come clean on how the study was paid for.)

As for FCA's claim that there aren't any federal regulations for on-road tests, that's a legitimate concern. After all, engineers' time is limited: like the rest of us, they focus their resources on meeting established benchmarks, not trying to manage every possible scenario.

However, it seems at best alarming that emissions would vary so significantly in on-road tests. Whether that's an unfortunate result of having no standards for on-road tests or a design flaw on FCA's part remains to be seen. 

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