Pros and Cons of Automatic Engine Start/Stop Solutions

Jeff Lynch
February 13, 2021
6 minutes read

The idea of ‘Idle Reduction’ is broad, complicated, and includes many technologies and solutions, including automatic start/stop engine solutions, that might work well together or conflict with each other. Each solution promises some type of benefit, but there is never a silver bullet that can be a perfect idle reduction solution.

The North American Council for Freight Efficiency (NACFE) put together an excellent review and report of all the idle reduction solutions on the market today, listing the advantages and disadvantages of each solution from a neutral position and looking at just the facts and research. If you aren’t familiar with NACFE, it is a great organization that provides in-depth and quality research to help fleets run more efficiently.

Automatic start/stop technology is becoming increasingly popular in various industries as it offers significant fuel savings and reduces emissions during idling.

The following is a copy of the NACFE’s report on automatic start/stop solutions. You can read the full NACFE Confidence Report by clicking here.

Overview of Automatic Engine Start/Stop Solutions

Functionality

Once the engine is running, the vehicle’s HVAC systems will warm or cool the sleeper just as they would when the truck is driving down the road. Essentially, the vehicle is still idling, keeping the engine warm and the batteries charged, but it is able to do so much more intelligently/efficiently, and automatically.

These systems can be used in very cold climates, for instance while a truck is in storage for a weekend or other down time, and offer very beneficial results, ensuring the vehicle will start when it is time to go back into freight-hauling operation. Automatic engine start/stop systems perform the work of both a block heater and battery charger without the need for the truck to be connected to outside power.

Types of Automatic Engine Start/Stop Systems

There are two different types of automatic engine start/stop systems, the most common being one that has a goal of maintaining a cab’s interior temperature when the vehicle is occupied. These may also assist with keeping the engine warm and the batteries charged.

The newer and less common type of automatic engine start/stop system focuses solely on maintaining the batteries’ state of charge. Given the growth in use of battery HVACs, combined with the new HOS restarts that last far longer than the 8 to 12 hours a battery HVAC can operate on one charge, this type of automatic engine start/stop system will probably grow in popularity, as they serve to recharge the battery HVAC system as it has drawn itself down. These will therefore enable battery HVACs to idle for longer than a single 8-10 hour window, allowing a driver to enjoy air conditioning continuously during an HOS restart. This type of automatic engine start/stop system is programmed to recognize the specific type of batteries being used by the battery HVAC system, and monitor their voltage, current draw, and temperature to provide optimal recharging patterns by comparing the inputs they receive to electronically stored battery-life models. It will typically require about 45 minutes of engine operation (which the automatic engine start/stop system will control) to fully recharge a battery HVAC system for an additional 8-10 hours of operation.

Advantages of Automatic Engine Start/Stop Systems

The most obvious benefit of all automatic start/stop systems is that they add few components and little weight to the vehicle. Since they are controlling the main engine, they do not require additional HVAC components, batteries, or engines to accomplish their tasks.

If a vehicle is purchased with a California Air Resources Board (ARB) “Clean Idle” engine, it will have a serial-numbered holographic sticker on the driver’s side of the hood or driver’s door. Such stickers allow automatic engine start/stop systems to be used without violating any idling regulations, provided that the vehicle wasn’t also purchased with the tamperproof five-minute timer, which does not allow any idling at all beyond that time limit.

Clean idle engines offer an integrated and clean solution that utilizes a few extra sensors to provide all of the desired HVAC and hotel load benefits while the vehicle is not moving. It may also be the solution most preferred by fleet maintenance teams, given its simplicity/commonality of diagnostics, service and parts.

Disadvantages of Automatic Engine Start/Stop Systems

The initial automatic engine start/stop systems that came out about two decades ago were not well-liked by truck drivers. Whenever those systems started and stopped the main engine, the noise and vibration could wake a sleeping driver. Some improvements have minimized this problem on newer systems, such as using the engine brake to create a more rapid and smooth engine shut-off than the cab rocking and engine sputtering that occurs during a normal shutoff.

Another drawback of these systems is that they do require idling the main engine, creating additional hours of wear on the main engine and loading of the DPF exhaust system.

Finally, it is not completely clear how various idle laws relate to some of the operational modes available with these systems. If the automatic engine start/stop system is charging the batteries or allowing a regeneration of the DPF system, it should be permissible to allow engine operation longer than the typical five minute maximum, similar to the rules which govern aspects of the electronic engine idle parameters technology class, and are detailed in that section.

Recommendations and Best Practices

If your fleet is dissatisfied with the length of operation of your battery HVAC system, a battery monitoring and charging system, such as that offered by automatic engine start/stop systems, could be a desirable investment to extend operation.

For fleets that are challenged from a support aspect to keep diesel APUs systems in operation, the combination of a Clean Idle engine and an automated engine start/stop system could reduce that challenge.

Again, the information in this post is from NACFE’s report on automatic engine start/stop solutions. You can read the full NACFE Confidence Report by clicking here. Feel free to visit our website or contact us directly at 913-744-4353 to see if Idle Smart can help you.

Interested in reducing the idle time of your fleet? Let’s talk to see if we’re a good fit for your fleet.

The Siren Song of “Included” Technology

It’s easy to assume that the factory-installed auto start-stop systems in your new trucks are a win. After all, they;re already there, part of the package, seemingly free and convenient. Taking a”good enough” approach promises to cut down on idle time and save you money, but it often hides a darker truth. Beneath the surface of these pre-packaged solutions are significant long-term costs and operational challenges that can erode your bottom line and create friction for your team. When every dollar counts and market volatility is a top concern, a system that only pretends to work isn’t just an inconvenience; it’s a liability.

This blog pulls back the curtain on why factory-installed Auto Start-Stop systems often fall short, using recent data from the American Transportation Research Institute’s (ATRI) Addressing the Shortage of Qualified Diesel Technicians report to highlight the hidden costs and operational strain they create. You’ll see how a purpose-built idle reduction system can provide the predictable savings, control, and efficiency your fleet needs to succeed.

The Hidden Costs of Auto Start-Stop Systems

Your trucks’ built-in idle solutions were designed for individual vehicles, not for the complex needs of an entire fleet. This fundamental design flaw creates a cascade of hidden costs that directly impact your operations.

Inconsistent Performance & Fleet Friction

A Freightliner with an OEM system operates differently than a Mack, and a Peterbilt operates differently from a Volvo. This lack of standardization means it’s impossible to create a single, fleet-wide idle reduction strategy. This inconsistency creates a significant training burden for a technician workforce that already struggles with a lack of qualifications in key areas. A majority of first-time untrained techs are unqualified in every core skill area, and more than 30% of trained techs are still unqualified in key areas like electronics and brakes when they start their careers. This issue is further compounded by a lack of in-depth training on the ever-evolving electronic systems in modern trucks.

The Training and Maintenance Burden

The ATRI report notes that employee hiring, training, and retention was a diesel shop’s greatest challenge in 2024, with over 65% of shops reporting they were understaffed in 2025. This shortage is exacerbated by the high cost of training new hires, especially those without formal education, who require approximately 357 hours of training and cost an average of $8,211 in wages alone to get them up to speed. Factory idle systems worsen this problem by requiring specialized diagnostic tools and mandatory dealer visits for troubleshooting and parameter changes. These trips take trucks off the road and incur costly downtime, frustrating drivers, technicians, and fleet managers alike.

“Good Enough” Is a Major Liability

Relying on “good enough” technology is a major liability. OEM automatic start-stop systems offer limited, reactive protection. For example, they monitor a battery’s state of charge but often fail to actively manage its overall health. This can lead to unexpected no-start situations that still require costly roadside assistance and disrupt your schedule. Similarly, in high-heat conditions, a factory-installed parking cooler may only provide 3-4 hours of operation instead of the advertised 8, forcing drivers to idle their engines to stay comfortable and completely negating any fuel savings.

Idle Smart’s Proactive Approach to Idle Reduction

Moving beyond the limitations of OEM solutions means adopting a system built specifically for fleets. Idle Smart’s proactive approach gives you the control, consistency, and data you need to drive real results.

Fleet-Wide Consistency and Customization

Unlike Auto Start-Stop systems that differ between truck brands, Idle Smart installs on all Class 7 and 8 trucks, regardless of their make or model. This provides one single, uniform system for your entire fleet. Our platform offers extensive customization with over 30 adjustable parameters that can be changed remotely through the SmartPortal, eliminating the need for shop visits for simple adjustments and allowing you to tailor the system to your specific operational needs.

Actionable Data vs. Guesswork

While OEM systems provide a limited view of idle behavior, the Idle Smart SmartPortal gives you a full picture of

why your trucks are idling. This actionable data allows fleet managers to make informed decisions that save money. Our predictive maintenance tool, SmartInsights, takes this a step further by translating raw ECM data into prioritized, actionable alerts, enabling a proactive maintenance strategy that prevents major breakdowns before they occur.

Proactive, Not Reactive

Idle Smart is a proactive solution. The system’s patented Battery Protect™ feature continuously monitors voltage and automatically starts the engine to recharge batteries before they become critically low, preventing no-starts. The Cold Start Guard™ feature does the same for coolant temperatures, preventing cold-start failures and fuel gelling in harsh weather. This proactive approach ensures your trucks are always ready to roll, eliminating the frustration and cost of unexpected roadside delays.

Moving from “Good Enough” to Unmatched Efficiency

The hidden costs of OEM Auto Start-Stop systems—inconsistent performance, a heavy maintenance burden, and reactive, “good enough” protection—are slowly eroding your fleet’s bottom line. The initial appeal of a bundled solution gives way to a painful reality of lost time, frustrated drivers, and unexpected costs that simply add up over the life of a truck.

The smartest fleets are moving beyond this model and choosing a strategic alternative. Idle Smart is a solution purpose-built for fleets to provide unmatched control, proactive maintenance, and measurable savings across all trucks. The value isn’t in “getting something for free,” but in gaining a reliable, efficient system that actually works.

Don’t let a “free” solution cost you more in the long run. Our team is here to walk you through a detailed analysis of your fleet’s current idle behavior and show you where the real opportunities for savings lie.

Schedule a call with our team to see the difference for yourself.

The Shocking Truth Behind the Diesel Technician Shortage: ATRI’s Latest Report Is In

Discover why diesel technicians are leaving according to ATRI’s reporting....

The diesel technician shortage is a persistent and growing problem. The American Transportation Research Institute (ATRI)’s Technician Shortage report states that a majority of shops (65.5%) reported that their locations were understaffed in 2025, with an average vacancy rate of 19.3%. This isn’t just a number; it’s a daily struggle that impacts uptime, maintenance costs, and operational stability. Compounding the issue is an annual turnover rate of 16.5%, with understaffed shops experiencing a higher rate of 18.1% compared to fully staffed shops’ 7.8%, meaning the cycle of hiring, training, and losing talent never seems to end.

In response, many fleets have focused on increasing pay, but as the data shows, that’s not the whole story. The report indicates that the shortage is also caused by issues with training, recruitment, and retention that go well beyond just compensation or company size. The reality is that modern technicians are looking for more than just a paycheck; they’re searching for a fulfilling career where they can apply their skills to meaningful work. The smartest fleets are beginning to realize that the key to winning the talent war lies not just in offering a competitive wage but in creating a proactive culture that prioritizes their team’s professional growth and job satisfaction.

What Techs Really Want (and Why They’re Leaving)

To understand how to attract and retain technicians, you must first understand what drives them to leave. The ATRI report offers some insight: nearly 44% of trucking techs surveyed were considering alternative employment.

The Firefighting Trap: Technicians ranked “more interesting work” and “variety of work” as top motivators for choosing a job. Conversely, a lack of variety was a top motivator for techs considering other jobs. When a technician’s day is filled with a constant stream of low-value, repetitive “firefighting” from unexpected breakdowns, it’s easy for the work to lose its appeal.
The Burdens of Training: New hires, especially those without formal training, require an average of 357 hours of employer-sponsored training just to get up to speed. This investment of time and money is a significant burden for a short-staffed team. What’s more, the report shows that even formally trained technicians often feel unprepared, with over 30% reporting they were unqualified in core skill areas when they started their careers. This lack of qualification is also related to one of the biggest challenges cited by training programs: that many aspiring techs struggle with basic math and reading skills. The lack of confidence and hands-on knowledge in areas like electronic systems and diagnostics can make their first few months on the job feel overwhelming. In fact, according to WrenchWay, only 28 percent of techs thought that their shop did a good job of teaching new techs, and 48 percent of techs thought that their shop did not do a good job
The Power of a Positive Culture: The report found that a lack of mentorship and poor shop training were significant barriers to a new technician’s career. On the flip side, strong relationships with colleagues ranked as a top source of job satisfaction for technicians already in the industry. Apprenticeship programs, in particular, are an effective retention tool, as techs who complete them have a turnover rate of only 6.9%, which is 58.2% lower than the overall average. This shows that a supportive, well-managed environment is a powerful, yet often overlooked, retention tool.

Creating a Proactive Maintenance Culture

So, how can fleets use this information to their advantage? The answer lies in a fundamental shift from a reactive “break-fix” model to a proactive “predict-and-prevent” model. This change empowers technicians, reduces the daily grind, and shows a commitment to an efficient, forward-thinking future.

The right technology is not a replacement for skilled labor; it is an enabler. Tech can take the burden of mundane tasks off your team while providing the data and intelligence needed to solve more complex problems.

A strong solution should:

Automate the Mundane: Automate routine checks and maintenance-related tasks to free up technician time for more complex, engaging projects.
Provide Actionable Intelligence: Translate complex data into simple, prioritized insights that enable your team to get ahead of problems before they become catastrophic.
Foster a Positive Work Environment: Help streamline workflows and reduce the stress of unexpected, high-stakes repairs, thereby cultivating a more positive and productive shop culture.

Approaching your maintenance team this way demonstrates a commitment to their professional development, creating an environment where technicians feel valued, challenged, and empowered to excel.

Finding the Right Partner to Build Your Culture & End The Technician Shortage

Tackling the technician shortage requires a holistic strategy that addresses the core frustrations of your team. The goal is to build a culture where technicians are seen as proactive problem-solvers, not just reactive mechanics.

This is where Idle Smart can help. Our solutions were designed to align with technicians’ needs:

Reducing the Mundane: Our core system automates battery protection and cold start guards, taking low-value, repetitive tasks off your technician’s plate, freeing up time for more challenging and rewarding work.
Empowering Proactive Work: Our SmartInsights predictive maintenance tool provides data-driven intelligence to predict and prevent major breakdowns, giving technicians more focused, valuable work to do so they can get your trucks on the road faster.
Building a Future-Proof Fleet: With a simple, ~1-hour installation and seamless OEM compatibility, Idle Smart reduces the training burden on your staff. It shows a commitment to an efficient, tech-forward future that attracts modern technicians.

Whether you’re ready for a full solution or just want to explore a more proactive approach, our team of fleet experts is here to help you build a culture that attracts and retains the best in the business.

Let’s Talk

How Idle Smart Helps Drivers Breeze Through CVSA Brake Week

Don't dread CVSA's 2025 Brake Week. Learn how Idle Smart...

It’s here: During August 24-30, CVSA’s 2025 Operation Airbrake is in full swing with its annual Brake Week. For drivers, it’s a week of heightened scrutiny, roadside inspections, and the tangible threat of being pulled off the road. For fleets, it’s a direct challenge to operational efficiency and profitability.

The numbers don’t lie. During CVSA’s 2025 Unannounced Brake Safety Day, 8.7% of inspected commercial motor vehicles faced immediate out-of-service orders due to brake-related violations. This isn’t an anomaly; it’s a consistent vulnerability. In 2024 Brake Week, approximately 13% of commercial motor vehicles inspected were sidelined for brake violations. These statistics highlight the unavoidable truth: unaddressed brake issues translate directly into lost revenue and operational chaos.

Your fleet doesn’t need to fear Brake Week. Instead, you can leverage it as a benchmark for year-round operational excellence. Idle Smart offers the precise tools to ensure your drivers are not only prepared for these high-stakes inspections but also consistently operate reliable, compliant trucks every day.

The True Cost of a Failed Inspection

A brake-related out-of-service violation during brake week is more than an inconvenience; it’s a multi-faceted financial hit:

Immediate Revenue Halt: A sidelined truck isn’t hauling freight. Every hour it’s parked for violations is revenue lost, disrupting schedules, and impacting customer commitments. CVSA mandates: “Commercial motor vehicles found to have brake-related out-of-service violations… will be removed from roadways until those violations are corrected”.
Emergency Repair Expenses: Rushed roadside repairs, towing fees, and expedited parts purchases are significantly more costly than planned maintenance. These emergency hits erode your carefully managed margins.
Driver Dissatisfaction & Turnover: Drivers value reliable equipment. Constant battles with unpredictable truck issues or the stress of failed inspections contribute to burnout and higher turnover rates in an already tight labor market.
Reputational Damage: Delays stemming from compliance issues can strain customer relationships and tarnish your fleet’s reputation for reliability.

Check out CVSA’s 2025 Brake Inspection Checklist.

Idle Smart: Your Strategic Edge for Brake Week & Beyond

Idle Smart equips your fleet with intelligent solutions that extend beyond the pressure of Brake Week, building driver confidence and operational reliability that lasts all year.

1. Predictive Insights to Prevent Brake Surprises

You can’t fix what you don’t see. Most fleets rely on reactive maintenance, only addressing issues once they’ve escalated or triggered a warning light. SmartInsights fundamentally changes this, catching potential issues before they lead to breakdowns.

Beyond Basic Diagnostics: SmartInsights, Idle Smart’s predictive maintenance solution analyzes complex ECM data to filter out noise and highlight potential issues before they become critical failures. This proactive approach helps your team identify subtle problems that traditional methods miss.
Targeting Hidden Vulnerabilities: While CVSA’s Operation Airbrake emphasizes physical components like drums and rotors, modern brake systems are complex, with electronic faults potentially impacting overall performance. SmartInsights provides critical, early warnings for issues such as Anti-Lock Braking (ABS) faults. Catching these system-level problems proactively ensures your entire braking system is functioning optimally, boosting your readiness for inspections and minimizing safety risks.

The Benefit: Your maintenance team gains critical visibility, allowing them to schedule and address issues like ABS faults during planned downtime. This prevents overloading your technicians with reactive, expensive emergency repairs caused by unexpected inspection failures during Brake Week.

2. Uptime Assurance: Ensuring Trucks Are Ready, Always

Idle Smart’s core features ensure confident drivers and consistent operations, not just during inspections, but throughout the entire year, freeing your team to focus on strategic maintenance instead of constant firefighting.

No-Start Prevention: Our Battery Protect™ feature precisely monitors battery voltage, automatically starting the engine to recharge before voltage drops too low, ensuring your drivers aren’t stranded or delaying pre-trip inspections due to dead batteries.
Engine & Fuel Line Safeguard: Cold Start Guard™ continuously monitors coolant temperatures, automatically starting the engine when needed to prevent costly cold start failures and fuel gelling. A healthy engine is fundamental to a compliant vehicle, reducing overall system strain that could indirectly impact brake performance.

The Benefit: By preventing the most common causes of unplanned downtime—battery drain and cold start issues—Idle Smart ensures your trucks are available for thorough brake inspections and ready for dispatch. This core reliability directly contributes to a fleet that passes inspections with confidence.

3. Data-Driven Preparedness via the SmartPortal

Effective compliance isn’t guesswork; it’s informed strategy. The SmartPortal is your command center for this data, giving you a clear picture of your idle and truck activity, from an individual truck to your entire fleet.

Holistic Health Overview: The SmartPortal gives you a clear picture of your fleet’s idling and drivers’ use of the system. Tools in the SmartPortal, like the Utilization Score (U-Score) and Truck Activity, highlight system use and driver behavior, helping you easily identify top performers, operational anomalies like excessive idling, and critical data like key position at any time of the day.
Strategic Action: The SmartPortal helps fleets find hidden trends and Insights to boost efficiency, ensuring systemic issues that might impact brake health, or any other critical component, are addressed before they become costly emergencies.

The Benefit: You gain the confidence of knowing your fleet’s status, enabling proactive maintenance scheduling and resource allocation. This strategic oversight ensures comprehensive readiness for Brake Week and consistent compliance every other week of the year.

The Executive ROI: Turning Compliance into a Competitive Advantage

Investing in Idle Smart’s proactive approach delivers measurable financial returns:

Maximized Uptime & Revenue: By preventing no-starts, cold start failures, and unexpected maintenance flagged by SmartInsights, Idle Smart ensures trucks remain on the road generating revenue and avoiding costly detours to the shop or roadside.

CVSA Data Insight: While 8.7% of commercial vehicles faced out-of-service orders during CVSA’s 2025 Unannounced Brake Safety Day and 13% during the 2024 Brake Week, Idle Smart helps position your fleet among the majority that consistently pass.

Reduced Operational Costs: Proactive maintenance minimizes expensive emergency repairs and extends the lifespan of high-value assets like engines and batteries.
Enhanced Driver Morale: Drivers appreciate reliable equipment and predictable schedules. Reducing their stress translates to higher job satisfaction and improved retention, which is more important now than ever.
Stronger Reputation: A fleet known for consistent reliability and proactive safety measures attracts top talent and fosters stronger, more dependable customer relationships.

Confidence on the Road, Every Day

Brake Week is more than just an annual check-up; it’s a magnifying glass on your fleet’s fundamental operational health. By investing in Idle Smart, you’re not just preparing for one week of inspections. You’re building a foundation of reliability, efficiency, and proactive management that benefits your drivers and your bottom line, every single day.

Ready to transform your fleet’s Brake Week experience into a confident stride toward year-round operational excellence?

Schedule a Meeting Today!

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