Is the Stop-Start technology detrimental or good for the car?

Question

I found a lot of articles on internet about how bad the stop-start technology is for your car and how it contributes to the faster wear of multiple parts, or how superb the feature is for the Sacred Environment and how it is Saving the Planet. However all the articles which I found are either ideological (one side or the other) or missing sources or both.

Is there any good scientific research measuring the actual fuel save in real realistic traffic, measuring the damage cause to the engine, the starter, the battery and other car parts, and comparing them together?

Can you please summarize the findings? I am not doing the research myself, I just want to know what is better for my car, and I want to have the feeling that the knowledge is backed by facts.

Answer 1

I always switch it off and would permanently disable it if that was an option. You need a stopwatch. Time each stop in your typical drive. Multiply that by at worst 0.5 gallons per hour. That's what you'd save, best case scenario.

The cynic in me says that if it saved a significant amount of fuel, there would be a display telling you how holy you have been.

Answer 2

My short investigations of google scholar with query "frequent start stop engine wear" resulted in some interesting articles:

• Santos, Nathália Duarte Souza Alvarenga, Vínicius Rückert Roso, and Marco Tulio C. Faria. "Review of engine journal bearing tribology in start-stop applications." Engineering Failure Analysis 108 (2020): 104344.

• Windover, Paul R., et al. Stop and Restart effects on modern vehicle starting system components. No. ANL-15/04. Argonne National Lab.(ANL), Argonne, IL (United States), 2015.

• Gudin, Dariusz, et al. “Experimental Measurement and Modelling of Plain Bearing Wear in Start–Stop Applications.” Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology, vol. 227, no. 5, May 2013, pp. 433–446, doi:10.1177/1350650112471287

• Bleijs, J. A. M., et al. “Wear Implications of Intermittent Diesel Operation in Wind/Diesel Systems.” Wind Engineering, vol. 17, no. 4, 1993, pp. 206–19. JSTOR, http://www.jstor.org/stable/43749514

• Sander, David E., et al. "Journal bearing friction and wear in start/stop operation." MTZ worldwide 78.2 (2017): 46-51.

You can find more information through surfing references of and to these articles or repeat my search.

About second part of the question - i apologize, but i do not have enough knowledge neither experience in servicing car engines and my current research fields are not connected to car engines, so i can not responsibly answer to this part. I suppose that it very depends on engine manufacturer, fuel and service prices, what will be cheaper for you - more frequent service and repair or more fuel consumption. This question is quite complex and can not be answered in general case, but in individual case investigation.