Month: December 2015


You may be waiting at a red light or you may have just started the engine and white smoke coming out of your tailpipe. Should you be alarmed? What should you do? You may want to ditch your truck for the day or you may want to ignore it. Neither is a wise approach. Get accustomed with the white smoke problem which is not normal but quite common with diesel engines.

Why the White Smoke?

There could be one or more reasons for your car exuding white smoke. The volume of white smoke will also vary. It could be insignificant or it could be voluminous. Let us get to the basics that can help you to understand the cause.

If coolant has entered the combustion chamber, then you will have white smoke emitting from the tailpipe. This could also happen if the engine has low compression. You can easily run a test to know for certain what the exact reason is. Pull the breather cap and look for smoke. If the engine is enduring excess blow-by then you would see white smoke emitting from the valve cover. You may need a technician to sort this out.

Worn out injectors can also cause white smoke. The injector may have a cracked tip, bad solenoid or harness. If the injector is damaged or worn out, then it may allow too much fuel in and that will affect the cylinder. If a cylinder goes down, then your diesel car or truck will emit white smoke.

Another common reason for white smoke is dropping coolant level. Some trucks have a perennial issue of dropping coolants. When coolants get into the engine, it can cause some severe damage over time. Don’t try to replenish the coolant and keep driving. Get your engine checked and fix the problem.

There are a few other causes of white smoke. The exact problem will depend on the vehicle and its specifications. In some models, the water and oil gets contaminated. Crankcases often get overwhelmed with water and radiators often have to endure excessive oil. You must try to steer clear from these issues. While these conditions are not entirely avertable, you must be quick to get them remedied. White smoke is just the symptom. You have to get to the root of the problem and fix it.


Diesel engines have been very popular in commercial vehicle but when people consider buying a personal car, the preference is inevitably the alternative. Diesel engines have become infamous over time but mostly because of certain myths that have remained firmly etched in our minds. It is necessary to debunk these myths. The focus on fuel economy and cost of running a car has ensured that people are getting interested in diesel engines. Time to shed light on a few facts and misconceptions.

  • A popular myth is that diesel is a dirty fuel and that vehicles powered by diesel engines will emit toxic exhausts and particulate matter. It is quite interesting to observe such myths because the EPA emission restrictions are very stringent and they don’t make any exceptions for diesel engines. Diesel powered cars have to adhere to the EPA restrictions so any thought that diesel cars will pump out more harmful gases and particulate matter than gasoline cars is just a figment of imagination. Also, cars today don’t emit the visibly black, white and grey dense smoke unless something is wrong.
  • There is another popular myth that diesel engines will go kaput when the mercury dips. This is a presumption that couldn’t be farther from the truth. There was a time when gasoline cars also didn’t start when it would be freezing outside. The trouble is not with the fuel. The problem is with the engine. Today, technology has ensured that diesel engines can have a cold start. It is true that gasoline is more flammable than diesel but vehicles don’t just start due to the fuel. The engine and the ignition technology play a role too.
  • Diesel engines are feared to be very noisy, sluggish and that they would lack in performance. This perception has developed from the fact that diesel engines have been primarily used in commercial vehicles, aka trucks and buses. Those vehicles are tilted towards viability and not comfort or exuberance. The diesel engines used in cars don’t have the same issues. The focus is on comfort, speed, quietness and all the attributes that one wants in a personal car.
  • Another myth is simply a misconception. That is that diesel fuel is hard to find. Nowadays most gas stations supply both gasoline and diesel.
  • Many people feel that diesel is more expensive. Some diesels can be more expensive than gasoline but most are not.


The Duramax engine is one of the finest ever to have been made for pickup trucks. But even the best can have a few faults. The original Duramax engine that rolled out back in 2001 and every variant that rolled out in the subsequent three years have a serious flaw. The fuel injectors are not among the sturdiest. The injectors have a substantial chance of failing, much before a hundred thousand miles. Should the LB7 injectors fail, they can leak substantial amount of fuel and dump it into the engine. This can happen when you are driving but also when your truck is idle. If the excess fuel leaked doesn’t get burned, then it can affect the oiling system and the engine will start to get filled with diesel. That is definitely not something you want!

While GM has offered an extended warranty to cover up to two hundred thousand miles, the injectors failing can be a bummer! LB7 injectors are pricey and they cannot be replaced unless one is very well trained. The injectors are so hard to reach that most people wouldn’t even be able to get to them, much less replace them.

When should you replace Duramax LB7 Injectors?

You must be observant of signs that your LB7 injectors have failed or have worn out. You may notice white smoke. Be careful because white smoke can also be a symptom of coolant loss or oil seeping into the radiator. But usually, white smoke is considered to be a cause of LB7 injectors’ failure in Duramax engines. Get your truck to a technician and one can test the balance rates of the injectors to know for sure if they must be replaced.

How to overhaul or replace Duramax LB7 Injectors!

First, the intake has to be removed. Then one must remove the fuel filter along with the housing and lines. One would then get access to the valve cover. The fuel injection control module has to be removed. It is typically mounted on the valve cover at the passenger side. There are several electrical and rubber connections that must be removed. Then you would get to the injector line. Take out the lower and upper valve covers and you would have access to the injectors.

The next steps involve removing the electrical connections, taking out the injector return line and then removing the injectors. You may need an injector puller for the job. Once the injectors in need of replacement are removed, new ones can be installed.