The GM engineers behind the Cadillac 3.6L engine are likely tired of the perpetual onslaught of issues the engine of this otherwise splendid car has encountered. Over the years since its launch, the Cadillac engine has received upgrades and improvements. But its owners still face multiple Cadillac 3.6 engine problems. Let us look into some of these faults or issues.
Arguably, the Cadillac is a great car. Users report reliable and high-end performance from the 3.6L power producer. In fact, it continued its success from the CTS into various vehicles, including the Chevy Traverse and the Holden Commodore. In 2008, the CTS was named Car of the Year by Motor Trend.
GM’s 3.6L Engine Venture
The first car to utilise the 3.6 Engine was the Cadillac CTS Sedan. Although, the 2019 CTS comes with the standard turbocharged 2.0L 4-cylinder engine. The 3.6L is optional, coming in either 335 or 420 horsepower Cadillac 3.6 engine hp variants.
GM has worked on this family of engines for close to 20 years now. By 2013, after a decade of development, the LF3 version had very little in common with the first 3.6L in production, the LY7. The only constant was displacement. At that point, Motor Magazine covered its journey, noting the significant changes introduced into its design.
Four versions of this engine came into being. At its most basic, the 3.6L engine is a 60° V6 with 24 valves and dual overhead camshafts. Called a high-feature engine, most versions have continuously variable cam phasing for the intake and exhaust valves. As a plus, it includes:
- electronic throttle control,
- oil-jet cooling for the pistons’ undersides,
- variable intake manifolds,
- forged cranks,
- sintered metal rods, and so on.
Cadillac 3.6 Engine Problems
When the 3.6 first entered production, the frequent timing chain failures disappointed users. A supplier provided sub-par timing chains for the engine. This issue existed for the first 2-3 years of production and achieved a solution in the years following. Also commonly reported was the miscalibration of the oil change indicator.
Improper Valve Timing
Low engine oil can disrupt the valve timing of the engine. Pistons may get damaged due to a collision with an untimely open valve.
Now, the Cadillac 3.6 uses about a quart of engine oil for every 2,000 miles of driving. There is space for about 6.02 quarts of oil inside the engine, so, technically, you get about 12000 miles of drive after an oil change. But, engine designs do not permit using the oil up to the end, and a refill is required around the halfway point.
Optimally, you should get a message that says, ‘Change Engine Oil’, somewhere at the 6,000 miles mark. But, the oil sensor algorithm of the Cadillac control system has improper calibration. The message is delayed to between 10,000 and 12,000 miles. By the time it does appear, you have driven about 6000 miles with less than half the required oil. Malfunction of the engine is inevitable.
In case of any damaged parts, you will have to replace them. Do not simply add some extra engine oil and call it a day. Take a look at the cylinders, the valves and the ignition coils. If you ascertain that no lasting damage has occurred to your engine and car parts, you can safely continue.
Misfiring Cylinders in the Cadillac 3.6 Engine
In some cases, the air-fuel ratio is incorrect. It leads to excessive carbon accumulation inside the engine, which clogs the valves. It is the main reason why the cylinders misfire in the Cadillac engine. There is not enough gasoline to burn, or there is too much. This is an issue that has cropped up many times.
Upon reporting it, Cadillac, as a response, usually asks users to utilise a fuel injector cleaning kit. They also advise the use of top tier fuels to keep the engine running well.
A cleaning kit may or may not help. One user reports that the air-fuel mixture discrepancy arises out of intake leaks. So, that necessitates a repair.
What Happens Due to a Defective Timing Chain?
Some slack in the timing chain can throw the pistons and valves into disarray. It works at first, somewhat erratically. Eventually, though, pistons misfire and the valve timing goes off-kilter. As a result, the engine starts making noises like an off-key trumpet player, and before you know it, your engine is destroyed.
Regular oil changes (i.e., more frequently than other cars) can stave off the failure point. So, at first, GM blamed users for irregular oil changes. However, GM later admitted that the so-called fix does not work. The problem still appears, even upon changing the oil at recommended intervals.
When Did GM Fix The Timing Chain?
In November 2012, GM announced a special coverage adjustment (#11340C) for timing chain wear in their 2.8L and 3.6L V6 engines (LP1/LY7/LLT). It was not an engineering solution. Rather than that, GM extended the warranty period on the timing chain to 10 years/ 120,000 miles. Thus, within this extra time, 2009 Enclave owners can obtain the replacement of a failing or stretched timing chain free of cost.
Those who have already paid for the expensive repairs (about $3200 to $3400) will be compensated.
Why is a timing chain repair so expensive? The chain itself is not costly. But, replacing it involves some lengthy and heavy labour, like taking out the entire engine and disconnecting the transmission. A stretched timing chain also causes damage to other components like cylinder heads, O2 sensors, camshaft position sensors, etc. If you study the timing chain diagram above, you can see the positions of various sensors.
However, 2010 Enclave owners may find themselves up a dry creek without a paddle because the warranty is limited to 2009 models.
More Problems With the 3.6 Engine
That is not to say that there were no more issues. If we take HotCars’ numbers, about 20 GM cars suffered extensive problems in 2018. The 2nd generation Cadillac CTS experienced a dead transfer case and transmission failures. A total of five 2009 model cars were recalled.
The 2020 XT5 still has Cadillac 3.6 engine problems. Going by the GM service bulletin, many faults like the following still exist in the latest models of the Cadillac:
- rough idle,
- misfiring due to excessive carbon on the valves,
- sticking valves,
- crank no starts,
- malfunctioning indicator lights,
- extending cranking situations
Let’s move on to problems specific to each generation of the Cadillac.
Cadillac CTS Sedan 1st Generation 2003-07
The first generation had the most engine-related problems. Repairs and workarounds are now available, though.
Cadillac CTS Sedan 2nd Generation 2008-14
The following video explains the 5 most common problems troubling Cadillac owners. You will also come to know how to overcome the issues.
Is the Cadillac 3.6 a Good Engine?
Yes, the 3.6 engine turned out to be a reliable product from GM. It has come to be respected for its fuel economy. Even without a supercharger, the 3.6 provides impressive horsepower for its size. Along with excellent low-end torque when paired with a 9-speed transmission. Present-day owners say it achieves its full power even at a moderate rpm. So, it seems to fit heavier vehicles perfectly.
The engines produced after the initial 3-year span seem to have impressed later buyers of the Cadillac. A particular family of four owns 6 cars and trucks with the Cadillac 3.6 engine. And they are satisfied. There have been no problems over the last few years of ownership. Moreover, one owner goes so far as to say that that is “one of the best engines which GM ever designed”.
What If There Are Too Many Problems?
It stands to reason that with so many problems cropping up in all generations of the Cadillac 3.6 engine, you don’t want to put up with its never-ending need for repairs. No need to worry. Depending upon the lemon law version of your state, your Cadillac may qualify as a lemon. If the same defect persists after a reasonable number of repair attempts (usually 3), you are eligible under the lemon law.
The same holds if the car is out of service for more than 15 business days during one such attempt. A lemon vehicle owner has the right to the cost of repairs, replacement, or a complete refund.
In parting words, we might say that Cadillac 3.6 engine problems are not too difficult to solve. Owners may be frustrated by the cascade of issues and faults. But, Cadillac has taken considerable strides in fixing the problems as they crop up. An experienced mechanic can diagnose the symptoms and replace faulty parts without hassle.
As the last step, if you feel the defects detract from its usability, your state’s lemon law will help you get a replacement or a refund.