The 4 Most Common Ford 3.5 EcoBoost Engine Issues. In 2010, Ford released 3.5 EcoBoost engines in the Lincoln MKS, MKT, Ford Flex, and Taurus SHO. The 3.5 litre twin turbo V6 engine was later used in a variety of other Ford and Lincoln cars in the years that followed. It has a powerful engine with 355 to 647 horsepower and plenty of torque. Turbocharging and direct injection further contribute to the 3.5 V6’s fuel efficiency and low emissions. Overall, the 3.5 EcoBoost is a fantastic engine, but no engine is flawless, and this is no exception. This post will go over Ford 3.5 EcoBoost engine issues and reliability.
Background on the Ford 3.5 Twin Turbo V6
Before delving into 3.5 EcoBoost issues, some prior information is required. The 3.5 EB comes in two generations, which we shall go over briefly below. This is crucial to state for a reason. Ford done an excellent job with several upgrades to the 2nd generation 3.5 EcoBoost engine. The improvements aid in the support of increased power and torque. They also fix a few reliability issues, making the 2nd generation Ford 3.5 twin turbo engine even more dependable.
3.5L EcoBoost 1st Gen
By no means is the first generation engine a bad engine. Combining turbos, direct injection, and VVT, on the other hand, was a departure for Ford. There are usually a few quirks to iron out, and the 3.5 V6’s were minor. We’ll go over this in detail in the following topic of typical 3.5L EcoBoost engine issues.
In any case, depending on the car, the first generation EcoBoost produces 355-380 horsepower. The smaller twin turbos spool quickly and produce a lot of low- and mid-range torque. It makes the 3.5 EB a perfect engine for towing and driving about town without using all of the RPMs. The first generation 3.5 EcoBoost engine can be found in the following Ford and Lincoln models:
- From 2010 through 2019, Ford Flex
- MKS 2010-2016 Lincoln
- MKT 2010-2019 Lincoln
- Ford Taurus SHO 2010-2019
- Ford Explorer Sport & Platinum (2013-2019)
- 2011-2016 Ford F-150
- Ford Expedition 2015-2017
- Lincoln Navigator 2015-2017
3.5 V6 EcoBoost 2nd Gen
Ford began offering the 2nd generation EcoBoost in select vehicles in 2017. In most versions, it is increased to 375-450 horsepower. Ford, on the other hand, took a step farther with a 647hp edition of the classic Ford GT. To support the power, the engine has some enhancements over the normal 3.5 EcoBoost.
Ford also added port-injection to the second-generation 3.5 V6 dual turbo engines. This helps to reduce carbon buildup, which will be discussed further in this article. Furthermore, due engine dependability issues with the prior design, Ford redesigned the timing chain. Another item we’ll look at. The 2nd generation engine is found in the following models:
- Ford F-150 models from 2017 to present
- Ford Expedition from 2018 till the present
- Ford F-150 Raptor (2017 and later)
- From 2018 till the present, Lincoln Navigator
- Ford GT (2017-present)
If you prefer to take this information visually, watch our Ford 3.5 EcoBoost Common Problems video below:
4 Typical 3.5 EcoBoost Issues
Let’s get some background information out of the way before we get into the meat of the matter. Among the most prevalent problems with the Ford 3.5 EcoBoost engine are:
- Carbon Accumulation
- Chain Timing
- Camera Phasers
- System of Ignition
As we briefly noted above, the top two issues primarily affect the first-generation 3.5 EcoBoost engine. With the second generation engine, Ford did an excellent job of upgrading some of the weaker points. Again, the 3.5 EcoBoost is a decent, dependable engine in general. Two of the “problems” listed above may not even be considered difficulties. Carbon buildup is merely an unintended consequence of adopting direct injection alone. Turbocharging has a negative impact on ignition system components such as spark plugs and ignition coils.
Having being that, we’ll go through these 3.5 EcoBoost issues in greater detail below. Let’s take a couple short notes first. Just because we label certain issues as prevalent doesn’t mean they impact a big percentage of 3.5 V6 engines. Rather, these are a few of the most prevalent problems that occur when something goes wrong. Furthermore, engines are prone to a variety of other issues that we are not mentioning, particularly as they age and mileage.
1) 3.5 EcoBoost Intake Valve Carbon Deposition
Carbon buildup is largely an issue with first-generation engines. The first-generation 3.5 EcoBoost uses solely direct injection (DI), which means fuel is shot straight into the cylinders. As a result, carbon deposits on the intake valves accumulate over time. Oil blow-by occurs in all engines to some extent. This oil travels down the intake tract, eventually coating the intake valves. Fuel washing over the intake ports and valves is a benefit of port injection. This helps to remove oil deposits and prevents them from collecting.
When you only have DI fuelling, however, there is nothing to help clean the ports and valves. Carbon deposits accumulate over time and impede airflow into the cylinders. It’s not a serious problem that has to be addressed right away. Some DI engines go their entire careers without having their valves cleaned. However, carbon buildup can cause power loss as well as a variety of other drivability difficulties.
Ford addressed this issue with the second generation 3.5 EcoBoost by employing both direct and port injection. In many ways, it’s the best of both worlds because DI provides several advantages over PI. However, utilising PI offers its own set of advantages, particularly in terms of preventing carbon buildup.
Symptoms of Carbon Build-Up in a Ford 3.5 TT V6
Excess carbon buildup on the 3.5 EcoBoost intake valves and ports causes the following symptoms:
- Idle time
- Stuttering or hesitancy
- Power outage
The majority of these symptoms are a result of the primary symptom, misfires. Carbon deposits can produce an uneven flow of air into cylinders. This destabilises the air-fuel mixture and may cause the 3.5 EB to misfire. This can result in symptoms such as fault codes, harsh idle, and stuttering. Another common indication of carbon buildup on the Ford 3.5L turbo engine is power decrease. However, because carbon build-up happens over time, it is frequently difficult to detect. You probably won’t notice power loss that happens gradually over a few years.
3.5L EcoBoost Carbon Buildup “Fix”
When the carbon deposits become too much, you should consider walnut blasting the intake ports. A good shop vac and walnut medium shells are required for the job. Otherwise, it’s largely just labour to get to the intake ports. Shops frequently charge $400-600+ for this job, so it’s not inexpensive.
Fortunately, it is not an urgent task that must be completed immediately, and you may not even want to do it at all. Carbon deposits should not pose a severe threat to the 3.5 EcoBoost’s lifetime. We would still want to do the work nonetheless. Walnut blasting should be done every 70,000 to 100,000 miles as preventive maintenance.
2) Timing Chain Issues with the Ford 3.5 EcoBoost
Specifics about the Ford 3.5 timing chain difficulties are difficult to come by. This is primarily a problem with first-generation engines. It appears to mostly affect 3.5 EcoBoost engines manufactured between 2010 and 2014. Ford improved the item before redesigning it for the second-generation 3.5L twin turbo V6. Timing chain difficulties tend to be more prevalent in F-150 models than in others. However, it’s possible that this is merely because the F-150 is the most popular model with the EcoBoost engine.
In any case, the problem at hand involves the lengthening of the timing chain. The 3.5 EcoBoost timing chain guides, tensioner, and cam phasers also have issues. If a fault arises, it is best to replace the entire timing chain assembly. Fortunately, Ford issued a service bulletin to address these issues. If you are out of warranty and are experiencing timing chain issues, you may be able to work with Ford.
These issues are usually urgent and should be addressed as soon as feasible. Additional harm to the 3.5 EcoBoost engines is conceivable if the timing chain fails completely. It’s a fairly rare occurrence, but it’s critical to fix the timing chain as soon as problems arise.
3.5L Ford Timing Chain Issues
Among the symptoms of timing chain, guide, and tensioner 3.5 EcoBoost issues are:
- The rattling of a cold start
- DTC P0016
- Engine light on
- Problems with drivability
One of the most prevalent indicators that something is wrong with the timing chain is rattling on cold starts. However, a variety of different factors can induce rattling. Also, expect the 3.5 EcoBoost to emit the P0016 error code, which will activate the check engine light. Finally, stretching the timing chain can cause ignition timing to be off and produce drivability concerns. This includes misfires, power loss, choppy idle, and other issues.
Timing Chain Replacement for EcoBoost
Replacing the timing chain and other components is not a simple or inexpensive task. It’s time-consuming, and the parts can mount up. While you’re there, you should think about replacing some more tiny items. Timing chain replacement is likely to cost several thousand dollars.
Many problematic 3.5 EcoBoost timing chains, however, were most likely replaced at some point. It’s a prevalent issue with the EcoBoost, but it doesn’t affect every engine. Some believe it is due to inadequate maintenance and an oil change history, or to the use of 20w oils, which are too thin for the engine. Ford also published bulletins, indicating that they are well aware of the timing chain issues. Even if it is not covered under warranty, you may be able to negotiate reductions or alternative compensation with Ford.
3) Cam Phaser Problems with the 3.5L Twin Turbo EcoBoost
The infamous cam phaser rattling is next on the list of Ford 3.5 EcoBoost issues. This primarily affects the 2017-2020 2nd generation 3.5L V6. The timing chain issues were rectified in the second generation engine, although this produced a difficulty with the cam phasers. Fortunately, Ford resolved the cam phaser problems in 2020.
The bad news is that cam phaser problems are extremely widespread, and are most likely the most common 3.5 EcoBoost issue on this list. At least for the 2017-2020 models, which are the most affected by cam phasers. Ford did, however, release Customer Satisfaction Programme 21N03, which essentially extends the warranty for cam phasers until January 1, 2023. However, depending on the exact mileage, Ford will only reimburse a fraction of the cost (or none at all).
The good news is that 3.5 EcoBoost cam phaser issues have no effect on performance or safety. As a result, the 3.5L V6 cam phasers do not require immediate repair. The rattle, on the other hand, can be both annoying and embarrassing. It’s also a good idea to replace the VCT phasers to avoid any future reliability issues.
Symptoms of a VCT Phaser
Among the symptoms of 3.5 EcoBoost cam phaser issues are:
- The rattling of a cold start
- Engine tremors
The most common sign of cam phaser difficulties is rattling. It is most prevalent during cold starts, although some people also notice rattling while accelerating. In the worst-case scenario, the rattle may be continual. According to Customer Satisfaction Programme 21B10, Ford originally tried reprogramming the PCM to eliminate the cam phaser rattle.
However, because the reprogramming caused engine trembling, Ford released 21N08. This programme only required dealers to revert the 3.5 EcoBoost to its original programming in order to eliminate the trembling. Finally, engine trembling is a potential indicator of 3.5 EcoBoost cam phaser issues.
Cam Phaser Replacement for 3.5 EcoBoost
Hopefully, your 3.5 EcoBoost is covered by the extended warranty. In this situation, Ford will cover all or part of the cost of repairing the cam phasers. Even if you’re out of warranty, it’s still a good idea to contact Ford corporate; they may be able to assist you even if the EcoBoost is no longer covered by the cam phaser extended warranty.
If it doesn’t work, you’ll have to pay for the cam phaser replacement out of pocket. Because it is a labor-intensive procedure, it is also advisable to replace other parts in the region. The timing chain, tensioner, guides, seals, gaskets, and all four cam phasers need all be replaced. A repair business will most likely charge between $2,000 and $3,000 for the entire job.
4) Problems with the Ford 3.5 V6 Spark Plug and Ignition Coil
This is largely here because we’ve run out of other 3.5 EcoBoost issues. Calling spark plugs and ignition coils a “issue” is probably not accurate. It is, however, inherent in owning a dual turbo, direct injected engine. We are very familiar with this as BMW employees. Because of the extremely high cylinder pressures, turbos exert a lot of strain on the ignition system.
On normally aspirated engines, spark plugs frequently last 70,000 miles or more, while ignition coils typically last about twice as long. The ignition components on the 3.5 dual turbo EcoBoost engine, on the other hand, are expected to wear out much faster. It’s usually simply normal wear and tear, but problems might arise at any time. This is quite straightforward on any engine, and the 3.5L V6 from Ford is no exception.
Ignition components can cause a slew of symptoms and drivability issues, so don’t dismiss basic spark plugs or coils. Spark plugs will most likely need to be replaced every 40,000 to 60,000 miles on stock 3.5 EcoBoost engines. The ignition coils should last nearly twice as long. If you run a tune, mods, or drive the 3.5 EcoBoost aggressively, the ignition parts’ lifespan can be severely reduced. Every 10,000 miles, our customised twin turbo 335i with the N54 engine requires new spark plugs. If we’re lucky, ignition coils will last 25,000 miles.
Symptoms of the Spark Plug and Ignition Coil
Symptoms of a faulty spark plug or ignition coil include:
- Idle time
- Misfire codes (check engine light)
These symptoms are common in plugs and coils. We usually recommend changing all six spark plugs or ignition coils at the same time, especially if they haven’t been changed in a while. If you’re suffering misfires, here’s an easy way to determine whether the problem is with a spark plug or a coil. Examine the trouble codes to see which cylinder(s) are misfiring. Remove the ignition coil from that cylinder and replace it with one that is not misfiring. If the misfire continues with the new cylinder, you’ve found your problem.
If that doesn’t work, you can try the 3.5 EcoBoost spark plugs. You might also consider simply replacing the spark plugs. It’s a simple and inexpensive fix.
Replacement Ford 3.5L Plugs and Coils
Again, the procedure described above is a useful way to pinpoint the source of the problem. Spark plugs are frequently to blame since their lifespan is much less than that of ignition coils. Fortunately, a set of 6 Ford 3.5 spark plugs typically costs between $40 and $100, depending on where you buy the parts. It’s a simple task that almost anyone can complete in the driveway in under an hour or two.
A set of ignition coils costs between $200 and $300. It is, however, a far simpler task than changing the spark plugs. You can do it yourself, or if you want, a repair shop should be able to do it for less than $100.
Reliability of Ford 3.5 EcoBoost
Is the Ford 3.5 EcoBoost engine trustworthy? Yes. We believe the Ford 3.5 twin turbo engine is more reliable than average. There aren’t many typical problems with these engines. Furthermore, Ford did an excellent job of correcting some of the issues with the second generation 3.5 EcoBoost.
Of course, in some circumstances, the reliability of each 3.5 V6 engine is determined by the luck of the draw. It is one of the things over which we have no control. You can, however, manage how effectively the twin turbo EcoBoost engine is maintained. Change the oil on schedule, use high-quality oils, and address any issues as they arise.
If you take care of the 3.5 EcoBoost, it will most likely reward you with a pleasant, dependable driving experience. Turbo engines require more maintenance, but we believe it is worthwhile in the end. Ford EcoBoost engines provide outstanding power, torque, fuel efficiency, and towing capacity. Most 3.5L V6 EcoBoost engines should have no trouble reaching 200,000 miles or more. Not too shabby in terms of longevity.
Summary of Common EcoBoost Issues
To be fair to the Ford 5.0 Coyote engine, we believe the 3.5 EcoBoost is the clear winner if you have the choice. The Ford 3.5 EB has an excellent blend of power, torque, towing capacity, efficiency, and so on. The use of two turbos also opens up a world of tuning possibilities for those looking to get the most out of their engines. The 3.5 EcoBoost is a great engine, but no engine is perfect.
Earlier gen 1 engines experienced timing chain failure and carbon buildup. Timing chain concerns are probably not as widespread as some would have you believe, but they are something potential owners should be aware of. Direct injection causes carbon deposits on the intake valves, which might create drivability concerns. Ford did an excellent job of fixing these issues after they were identified.
Otherwise, keep in mind that turbo engines can be a little more difficult to maintain. The turbo boost pressures put a lot of strain on the spark plugs and ignition coils. Turbo engines, such as the Ford 3.5 EcoBoost, have more elements that could fail. Nonetheless, turbo technology has advanced significantly in recent decades. Maintain the Ford EcoBoost engine properly, and it will most likely reward you with a dependable, enjoyable driving experience.