Johnson: Auto Stop-Start, Oil Monitors, and Severe Service Intervals

Those new vehicle sales pitches sound great especially to average consumers who want improved fuel economy but have no training in internal combustion engine maintenance. A new device that makes SUVs and trucks burn less fuel at stoplights? Wonderful. An electronic oil monitor that tells you when to change the engine’s oil? Even better. Everyone can stop worrying about checking their oil, which, frankly, has been a drag for non-mechanically inclined consumers since full-service gas stations disappeared in the 1990s. Right?

Wrong.

When it comes to Corporate Average Fuel Economy-related fixes, where automakers giveth, they usually taketh away. That’s largely because dropping the fleet’s weight was the most obvious way to improve CAFE rates from 1978 to the present, but consumers wanted more and more SUVs and trucks, and there’s only so much improvement to be squeezed from a five to 10,000 pound vehicle capable of going off-road and towing while meeting safety standards.

Auto stop-start, also known as idle-stop, is one such CAFE-related improvement. For anyone who has been hanging onto an older vehicle, auto stop-start is the reason so many newer SUVs and trucks seem to have stalled next to you in traffic. They’re not actually stalled; they’re automatically shut down to prevent burning fuel. Many consumers end up hating it (search “consumers hate auto stop-start” if you think that’s an exaggeration.) And some have experienced frightening problems with their vehicles failing to restart promptly—Honda Ridgeline is one example. Auto stop-start also creates unadvertised service dilemmas—it arguably exacerbates starter motor wear and the impact of severe service conditions.

“Frequent stop-and-go traffic” is a hallmark indicator of severe service driving conditions, and that was before stopping at a light might involve turning off the engine every time. The starter motor gets more than double the use with auto stop-start. Although automakers reportedly planned to improve their starter motors to accommodate the increased burden, a brief survey of recent manufacturers’ communications submitted to the National Highway Traffic Safety Administration indicates starter problems abound in vehicles with auto stop-start:

• Chrysler TSB 9100195 Issue Review System—Starter Engine dated August 28, 2023 (“Due to Starter No Trouble Found claims, please contact FCA Redacted Content prior to repair” for 2022-24 Chrysler Pacifica, 2022-23 Dodge Durango, 2022-23 Jeep Wagoneer & Grand Wagoneer, 2023-24 Jeep Wrangler, and 2022-24 Ram 1500).
• Audi TSB Special Parts Collection Code: 27K4 dated November 21, 2023 (free starter replacement for certain 2022 AUDI A3).
• Ford TSB 23-2347 Illuminated MIL dated November 9, 2023 (Belt Integrated Starter Generator problem in 2023 Ford Explorer, 2020-22 Ford Explorer Hybrid, 2021-23 Ford F-150, and 2020-23 Lincoln Aviator).
• General Motors TSB 21-NA-279 Rattle Type Noise dated September 2023, (Starter pinion gear may be loose and making contact with the flywheel. Inspect and, if necessary, replace the starter in 2021-23 Buick Envision, 2020-23 Cadillac CT4 & CT5, 2019-2023 Cadillac XT4, 2020-23 Cadillac XT5 & XT6, 2019-23 Chevrolet Blazer, and 2020-2023 GMC Acadia).
• Infinity Daimler ISS Reprogram Voluntary Emission Recall Campaign NHTSA ID 10237598 (The ECM reprogram is intended to improve the idle stop/start functionality after 250,000 starter operations for certain 2016-19 Infinity Q50 and 2017-19 Infinity Q60).

That’s only a small subset of 100s of newer manufacturers’ communications that include cited issues with starters. According to major lubricant manufacturers, the multitude of extra start events also promotes reduction in the boundary lubrication required to prevent connecting rod bearing wear.

Now combine those risks with electronic oil minders—the algorithmic approach some automakers rely upon to eliminate formal oil change service intervals. The idea of following the oil minder’s signals on the dashboard seems straight-forward, but the owner’s manual will always contain contradictions. Chief among them is the direction to check the oil at every fuel stop because the automakers know (a) the oil minder isn’t testing oil quality or quantity, (b) severe driving conditions can dramatically shorten the typically emphasized longest possible oil change interval, and (c) new tech and manufacturing defects are performance wild cards.

No matter how progressive and foolproof automakers make their equipment sound at first blush, the owner still gets the burden of making sure the engine works properly the old-fashioned way. If consumers aren’t going to check their oil at each fuel stop—and we already know they don’t from PAMA’s work with the Service Station Dealers of America—then a severe service interval makes the most sense especially if they have auto stop-start.