Editing Start-stop system (section)

==Concerns==
Hybrid/electric assist vehicles experience almost no delay in power from a stop, thanks to the instant availability of power from the battery to the electric motors. Gasoline and microhybrid vehicles, on the other hand, generally experience slight delays (albeit fractions of a second).

In February 2001, the US [[National Highway Traffic Safety Administration]] (NHTSA) raised questions about non-hybrid Honda vehicles equipped with the company's "Idle Stop" transmissions due to concerns over the "sudden lurching forward of a vehicle in an automatic restart" – rather than the "gradual creeping forward found in current transmission designs".<ref>{{cite web|url=http://www.autocentral.com/article.mvc/NHTSA-puts-brakes-on-Hondas-Idle-Stop-transmi-0001 |title=NHTSA puts brakes on Honda's 'Idle Stop' transmission technology |publisher=Autocentral.com |date=2001-02-15 |access-date=2011-05-29 |url-status=dead |archive-url=https://web.archive.org/web/20110904181023/http://www.autocentral.com/article.mvc/NHTSA-puts-brakes-on-Hondas-Idle-Stop-transmi-0001 |archive-date=2011-09-04 }}</ref><ref>{{cite web|author=Stephen R. Kratzke |url=http://www.federalregister.gov/articles/2003/05/15/03-12051/federal-motor-vehicle-safety-standards-transmission-shift-lever-sequence-starter-interlock-and#h-13 |title=Federal Motor Vehicle Safety Standards; Transmission Shift Lever Sequence, Starter Interlock, and Transmission Braking Effect |publisher=Federalregister.gov |date=2003-05-15 |access-date=2011-08-02}}</ref>

A common issue of stop-start systems is that long-term use may induce additional wear due to lack of oil lubrication. For the crankshaft bearing half shells and the big end bearings this can translate into frequent high-speed rotary movement before a hydrodynamic film is established. During this phase of boundary lubrication, metal-to-metal contact can occur between the crankshaft surface and the bearing's sliding surface. This was not an issue while the number of engine restarts totaled what was generally understood to be a normal magnitude. However, in a vehicle with a start-stop system this effect can necessitate new technological solutions to avoid premature bearing wear, depending on the driving cycle. Consequently, future engines for start-stop applications need to be designed for 250,000 to 300,000 starts. Traditional bearing shells with aluminum or copper lining show severe wear after only 100,000 cycles.<ref>{{cite web |url=http://oil-synthetic.com/2019/10/28/start-stop-technology-in-engines-can-increase-bearing-wear/|date=28 October 2019 |title=Start-Stop Technology Can Increase Bearing Wear |first=David |last=Consalvo |publisher=AMSOIL Dave}}</ref>{{sps|date=September 2021}}

Some implementations do not use a starter motor,{{Citation needed|date=September 2018}} eliminating concerns of starter motor wear. The [[Mazda]] i-stop used in the Mazda3/Axela line (in Europe and [[Japanese domestic market|JDM]]) uses combustion to assist the starter motor by sensing the position of the piston in the cylinder. They claim quieter and quicker engine restart within 0.35 seconds.<ref>{{cite web|url=http://www.mazda.com/mazdaspirit/env/engine/siss.html |title=Idling stop technology &#124; Environmental Technology |publisher=MAZDA |access-date=2011-05-29}}</ref>

Some car makers such as Suzuki have one lithium-ion battery inside the car.<ref name="lepoint.fr"/>

The [[US Environmental Protection Agency]] offers gas mileage rating incentives to car manufacturers who ensure their auto stop-start systems default to the "on" position{{fact|date=May 2025}}. If the system is "non-latching" (i.e., it does not stay off after the car is switched off), the EPA only calculates fuel economy figures when the system is engaged. If the car manufacturer allows the system to be permanently disabled, then the EPA tests the fuel economy with the system both on and off, then averages the two fuel economy figures. Since that average will always be lower than the economy with the system engaged, car manufacturers choose to switch it back on when the vehicle is restarted,<ref>{{cite web |last=Muller |first=David |date=10 April 2018 |website=Car and Driver |title=Automakers Increasingly Offer Ways to Deactivate Stop/Start Systems (Temporarily) |url=https://www.caranddriver.com/news/a19561461/automakers-increasingly-offer-ways-to-deactivate-stopstart-systems-temporarily/}}</ref> which some operators find inconvenient.<ref>{{cite web |last=Wagner |first=Jeff |date=18 October 2022 |title=Is stop-start technology really beneficial for your vehicle? |url=https://www.cbsnews.com/minnesota/news/is-stop-start-technology-really-beneficial-for-your-vehicle/ |publisher=CBS News Minnesota}}</ref>