Ever wonder why EGR delete kits are so popular for the new diesels? Allow me to present Exhibit A: You’re looking at an intake air temperature sensor we removed from the manifold of our ’10 Ford F-350. As you can see, the sensor is covered with a sooty, sticky goo. It’s a carbon mess, and I’m outraged this disgusting gunk is forming inside our 100-percent-stock engine that has only 30,000 miles.
“Where is this junk coming from?” you ask. This is what can happen when a diesel is forced to run extreme amounts of exhaust gas recirculation (EGR) in conjunction with a closed-crankcase breather system. I’ll confess our 6.4L represents one of the worst-case scenarios for this buildup, because it makes a ton of short trips that don’t allow the engine to get up to operating temperature. Still, I find myself asking, “Why do we even bother to run an air filter on the engine, if this is the sludge the Power Stroke was designed to cope with in its intake manifold?”
Deleting This and Disabling That Only Holds Diesel Back
I know what some of you are thinking. I should ditch the 6.4L’s EGR system and do away with the DPF while I’m at it. I’ll admit doing so would make the engine last longer—but it would also be illegal, void the warranty, and make the truck impossible to smog test in California. Yet those aren’t the reasons we’re going to leave our engine’s emissions systems in place. Nope, we’re keeping these clean-air band aids so we can find ways to actually improve modern-day diesels. Because even though our Power Stroke is loaded down with add-ons designed to meet its emissions requirements—taking them all off is a shortcut to nowhere. We can make this Power Stroke run better, improve its fuel economy, and still get it to burn clean.
How Clean Diesel Laws Improve Engine Performance
I can almost hear a few of you saying, “How in the world could those !@#$ emissions laws that are ruining my diesel ever improve anything?” That’s a fair question, but allow me to let you in on a secret: The same technology our diesels use to make the extreme horsepower and torque is the same technology that was first implemented to actually make our engines run cleaner.
I know we don’t usually talk about them in these terms, but common-rail injection, turbochargers, intercoolers, four-valve-per-cylinder cylinder heads, cylinder pressure sensors, and even the P7100 injection pumps were all put into production to meet emissions laws. Ever notice how the 6.0L Power Stroke and the common-rail Cummins engine showed up on the market at the same time? As enthusiasts, we chalked that up to the horsepower war that was raging amongst the Big Three—but the thing that got common-rail injection on the Cummins and variable-geometry turbocharging on the Power Stroke was the new federal emissions requirement that went into place on January 1, 2003.
And emissions laws didn’t just create our modern-day diesels. We also owe them for the original 7.3L Power Stroke’s electronically controlled injection system, which made adding power to a diesel as simple as flicking a switch—a technology that changed our industry forever.
The pattern of clean-diesel technology basically goes like this: First, a new emissions standard is set forth, and the OEMs say, “We can’t meet those requirements with what we currently have.” That’s when the engineers step in, take control of the product from the bean counters, develop a new technology, solve the problems, meet the standards, and the new product gives enthusiasts a new tool to extract more power from our engines. Lest anyone doubt this, just wait. If we ever get a supercharged diesel, it’ll be because the OEMs needed a way to make their engines burn cleaner during throttle tip-in—not because they wanted more power.
The Truth About Exhaust Emissions
None of us—no matter where we live—has ever gotten up in the morning, gone outside, taken a deep breath, and said, “You know, the air here is just too clean.” Nope, that’s never happened. Not even once.
I think it’s clear diesel’s future success relies on us working to make our engines better in every way—not in finding ways to weasel around being clean because we were too lazy to figure out a better way to make power. I know I’ll have my work cut out for me with this 6.4L. But I owe it to you to work through the challenges. If I wanted to get stuck in a technological rut, I’d drive a gas vehicle.