What You Can Expect When You Delete The EGR

Posted on: 29 June 2018

Exhaust gas recirculation, or EGR for short, has been a prominent emissions control feature on diesel vehicles for decades. EGR systems are designed to reduce diesel particulate emissions by recirculating exhaust gases through the combustion chamber, reducing combustion temperatures, and preventing nitrogen oxides (NOx) from forming.

But while EGR systems do plenty of good for the environment, the same can't be said of the effects they have on your diesel engine. Reintroducing exhaust gases into the engine intake and combustion chamber often results in severe carbon buildup throughout the EGR system and the rest of the intake. It's not uncommon for EGR problems to result in turbocharger failure, head gasket failure, and severe piston damage.

EGR delete kits are popular among diesel performance enthusiasts who want to enjoy the performance benefits of their diesel engines without suffering an EGR system's drawbacks. So what happens when you decide to delete your EGR using one of these kits? Read on to find out.

Increased Engine Performance

One benefit you might notice immediately after an EGR delete is an increase in available horsepower. Mixing exhaust gases back into the combustion cycle actually sacrifices performance by limiting combustion temperatures. While this helps control NOx emissions, it also prevents the combustion chamber from burning fuel as efficiently as possible.

Disabling the EGR by disconnecting the EGR valve connector prevents the vast majority of exhaust gases from entering the intake stream. However, exhaust pressures can still force the EGR butterfly valve open at times. An EGR delete kit completely removes the EGR valve and blocks off the associated EGR ports, completely preventing exhaust gases from entering the combustion chamber.

Improved Fuel Economy

In order to achieve good fuel economy, your diesel engine needs to burn its fuel as thoroughly and efficiently as possible. To achieve optimal thermodynamic efficiency, diesel engines rely on lean-burn combustion and a compression ratio that's significantly higher than the ratio on comparable gasoline engines.

Reintroducing exhaust gases via the EGR system lowers combustion temperatures, which in turn reduces the engine's thermodynamic efficiency in favor of preventing NOx formation. Since lower combustion temperatures prevent the diesel fuel from burning thoroughly, your diesel engine won't be as fuel efficient as it should be.

An EGR delete prevents exhaust gases from mixing with fresh intake air, allowing combustion temperatures to increase and diesel fuel to burn more thoroughly. With these improvements, you can expect to see a significant increase in your diesel engine's fuel economy.

Reduced Soot Buildup

Soot is an unavoidable byproduct of the diesel engine's combustion process. Reintroducing exhaust gases into the combustion process also brings soot and other particulates into the intake and combustion chamber. This usually results in a buildup of soot and carbon deposits throughout the intake port, EGR valve, and virtually any other area that's exposed to exhaust gases.

Soot buildup can also occur within the combustion chamber, adding significant wear and tear on pistons and valves. Not only can excessive soot buildup choke the life out of your diesel engine, but it could also set the stage for piston failure or even major block failure in some cases. Turbochargers can also get gummed up by soot deposits, resulting in poor performance and a shortened turbocharger lifespan.

Removing the EGR system entirely allows soot and other diesel particulates to travel directly out through the exhaust system as intended, preventing soot buildup from occurring.

Increased NOx Emissions

There are a couple of downsides to an EGR delete. For starters, removing your diesel engine's EGR equipment will result in an increase in NOx emissions. However, it's not something you'll notice in daily driving.

The other downside comes if you live in an area with strict diesel emissions testing. An EGR delete may prevent you from passing your local jurisdiction's emissions tests, since most testing is done by scanning for increased NOx emissions. 

For more information, contact a company like Cantune.