If you’re having trouble with your Duramax, you’re not alone. There are many common problems with these engines, including fuel starvation, Air in the fuel lines, and difficulty bleeding the system. Here’s a look at the top problems associated with these engines. Hopefully, you can use this information to solve your own problems. But before you do, read this article to understand the problems more fully. If you’re still having trouble, we’ve compiled some helpful tips for you.
There are several causes of fuel starvation in a Duramax diesel engine, but the most common is a lack of a lift pump for the injection pump. Instead, this engine uses the factory gear pump on the back of the cp3 to draw fuel from the fuel filter housing or fuel tank. While this is fine for most situations, it’s not optimal, and it can lead to problems such as stalling and poor performance. To alleviate fuel starvation, you can install aftermarket fuel systems.
If your Duramax is approaching its prime, its fuel filter head is likely leaking fuel. The first step in fixing the issue is to replace the filter head. If your Duramax has a faulty filter, your GM dealer will likely suggest replacing the entire assembly. A better alternative to replacing the filter head is to purchase an aftermarket fuel system. You can repair the problem yourself, if you have some basic mechanical skills.
If you are concerned about fuel starvation in Duramax, you may want to consider buying a newer, more powerful engine. A new fuel pump can be a significant cause of engine failure. When a fuel pump fails, friction can cause it to fail. In addition to causing an engine to stall, metallic particles can form in the pump, resulting in catastrophic failure. Fuel starvation in Duramax can lead to catastrophic engine failure.
The age of a vehicle plays a role in fuel filter replacement intervals. After seven years of driving, dirt, rust and debris tend to accumulate faster. The most reliable indication of a clogged fuel filter is a reduction in gas mileage. Misfires and hesitations are also common indicators of a clogged filter. When your car has these symptoms, it may be time to replace the fuel filter.
Air in the fuel lines
There are a few reasons that air can be found in your Duramax’s fuel system. This problem can be caused by a number of different factors, including an improperly installed fuel filter, a stripped-out fuel sensor, and a cracked bleeder screw. In addition, if your vehicle runs on bio-diesel fuel or ULSD, there is a high risk of air bleed into the fuel system. If you suspect air in your fuel system, check for these causes and learn what to do to resolve the issue.
The fuel filter head is often the culprit when this happens. This component is often the source of the problem, as it sucks fuel from the tank and delivers it to the engine. If you notice air in your fuel lines, replace the filter head immediately. The fuel filter head can be a major source of air suckage, so it is critical that you replace it as soon as possible. If the filter head is the issue, you can also replace the filter by replacing the fuel filter, which is often the most common cause of crank but no start.
While a lift pump is a necessary component, it is not necessary for a Duramax to have one. In fact, the lack of a lift pump allows the stock Duramax to run with no problems. Despite its high-tech design, a lift pump is not necessary, so you can opt for a less expensive alternative if you want to save money. When the lift pump fails, your engine will need to work harder to start.
Difficulty bleeding the fuel system
If your 2001 to 2016 Duramax diesel engine has trouble running, you may have difficulty bleeding the fuel system. The bleeder screw may have become cracked or stripped, allowing air into the fuel supply. The bleeder screw is the most common source of this problem. A replacement is needed if you’ve noticed that your vehicle is not running right. The following are the common causes of a leak in the fuel system.
The 2001-2004 Duramax was plagued by premature injector failures. GM recalls the LB7 Duramax injectors and has since revised them to provide an extended warranty. The original injectors are located beneath the valve cover, and any fuel leaks could dilute the lube oil supply. Luckily, GM has since introduced the LLY engine generation, which redesigned the valve cover and moved the injectors outside the cylinder head. This change improved serviceability, made identifying fuel leaks easier, and eliminated many of the concerns that plagued the LB7 Duramax engine.
Another common cause of a crank but no start in a Duramax engine is a clogged fuel filter. The fuel filter clogs the fuel flow and prevents the fuel pump from generating the desired pressure. If your fuel filter is too dirty, it will inhibit the flow of fuel and result in a crank but no start. To prevent this, you should change the filter every 10k miles.
Another cause of Difficulty bleeding the fuel system is a bad CP4 fuel injection pump. In recent years, many Duramax owners have begun converting back to the CP3 pump, which had been used on most of the 2001-2010 Duramax engines and some 2003–2018 Cummin diesel engines. CP4s usually fail around 100,000 miles and destroy the fuel system. Replacing it is a major repair and can cost thousands of dollars.
Injector cup design flaws
GM has issued a Technical Service Bulletin (TSB) about injector cups, citing the problems with GMC motors. This problem occurs in the LBZ and LLY engines, which are used in medium-duty vehicles and pickup trucks. The TSB provides insight into diesel engine design and lets you know which parts to look for and how to repair them. Diesel engines are a complicated beast, and knowledge is power.
There are multiple theories about why the injectors fail, but there is no official reason for them to stop working. Fuel filtration may be a contributing factor, with filters typically filtering fuel down to seven microns. As a result, tiny debris could still make it through the filter, resulting in injector wear. Low-sulphur diesel fuel doesn’t provide the proper lubrication for the engine.
Early Duramaxes are prone to fuel injector failure, particularly at low speeds. When the injectors fail, the diesel fuel can leak from the oiling system and into the surrounding environment. Injectors can be expensive and difficult to repair, so GM extended the warranty on these parts to 200,000 miles. The company is also working to eliminate the problem and to make the injectors easier to replace.
The FICM is a critical component for the fuel system, as it controls the fuel mix. Injector lines must be replaced because they can become corroded by rust and other debris. External valve cover accessories hide these lines, but you must remove them to remove them. Once the injectors are replaced, the fuel filter housing and FICM must be reinstalled. Connect the air intake tubing and the filter box to the turbocharger. After completing all of these steps, the engine is ready to be started.
Oil leaks into turbocharger
When a 6.6L Duramax engine suffers from oil leaks, the result can be disastrous. While this can result in serious engine damage, you can avoid replacing the turbocharger entirely by diagnosing the problem at its root. Several factors can contribute to this problem, including a malfunctioning fan clutch or a failed water pump. A proper diagnosis will save you money and headaches later.
If you notice an increase in oil consumption, the turbocharger may have a leaking oil pipe. If this occurs, the turbo will no longer function properly. In addition to oil leaks, you may also notice a strange noise coming from the engine. These noises may be pleasant or annoying, depending on what type of vehicle you drive. A police siren noise could be the result of a faulty turbo. If you hear this noise, it could be caused by a loose pipe or malfunctioning turbo blades.
To check the turbine housing, loosen two bolts on the turbine housing and center housing. While tightening the bolts, don’t jostle the housing off its seating surface, as this could damage the wheels and cause damage to the engine. If there are two bolts holding the turbocharger to the engine, temporarily install it on the truck. Make sure to secure the turbocharger to the center housing with two bolts.
Another cause for Duramax oil leaks is a damaged head gasket. These parts are highly sensitive and expensive to replace, and many shops charge from thirty to forty hours of labor to do this repair. In addition to the price, you’ll need to remove many components from the engine to replace a failed factory head gasket. And because these components are often installed in a tight spot, a failed head gasket could result in catastrophic engine damage.