How to Clean your EGR System

Cleaning Your EGR System

The exhaust gas recirculation (EGR for short) system present in all Mazdaspeed 3 and Mazdaspeed 6 vehicles is known to have some issues. It is present from the factory to help with NOx emissions and likes to clog, throwing a check engine light in the process. The common solution to this is to do a full EGR delete, and use an AccessPort to clear the CEL.

While likely the best solution, it is not possible for all people to do, especially if you live in an area with extensive emissions testing. If this sounds familiar, read on as I explain what the EGR system does, how to clean it, and how to ensure you will pass emissions afterward.
The EGR system does exactly what the name says; it recirculates some of the exhaust gasses back into the intake system.

Through some fancy chemistry, this reduces the total amount of NOx that comes out of your exhaust pipe. In Mazdaspeeds the system consists primarily of the EGR valve and the tube that connects the valve back to the intake manifold. Over time, the carbon present in the exhaust builds up, causing issues for the system. If the valve cannot open/close all the way or the tube gets clogged, your car will likely throw a P0401 code, for insufficient EGR flow. Aside from being another pesky CEL, a clogged system can cause rough idling, poor MPG, and slow startups.

Tools and Products Needed:

  • Degreaser/Carbon Cleaner – This will really help break up the stubborn carbon, making it easier to clean the EGR valve/tube. B-12 Chemtool works the best, but regular brake parts cleaner or other strong degreasers will work as well.
  • Picks/Scrapers – The cleaner will get the carbon softened but you will need something to scrape at it and get the pieces out.
  • Flexible Round Brush – The EGR tube can be cleaned by just soaking in the degreaser and picking out the big chunks but a round brush works even better. I used a straight brush but I think this flexible one will work better.
  • Coolant – The EGR valve has a coolant passage so you will lose most if not all of the coolant in your overflow tank. Be sure to buy OEM Mazda coolant or at least coolant with phosphate organic acids to keep your cooling system healthy.
  • Assorted Tools – You will need a regular assortment of sockets and hand tools for this job. The only irregular tools are a 22mm wrench (you can use an adjustable wrench) and some small needle nose pliers.
  • OBDII Code Reader – Okay you don’t NEED this for EGR cleaning but who doesn’t love new toys? This one is great for reading any CEL codes and seeing when you’re ready for emissions (more on that later).

Now let’s get started!

  1. Start by removing the OE battery, battery box/tray, top mount intercooler, airbox lid, and turbo inlet pipe. Getting to the EGR valve is really the hardest part of this entire process. If you’re new to your Mazdaspeed and need some help removing any of these parts, MazdaSpeed Forums has a lot of resources if you just search for them. Be very careful when removing the small vacuum line on your turbo inlet pipe. The plastic barb likes to break off, causing all sorts of headaches down the road.

  2. Locate & remove the EGR valve. It is the small aluminum piece with a round plastic top. Loosen the clamp on the black rubber hose and drain the coolant that will come out. You will lose about what is present in your overflow tank, catching it with a cup prevents a mess in your engine bay. Remove the electrical connector and the two bolts that hold the EGR valve to the engine and the whole valve will come free. Be sure to keep track of the gasket between it and the engine.            

  3. Remove the throttle body. You must first remove the two coolant lines that run to the TB. Clamp them closed to prevent any extra coolant leakage. Remove the four bolts, and the throttle body will come free. Once again keep track of the gasket.

  4. Remove the EGR tube. There are two bolts located by where the EGR valve was removed. Another gasket located here. Trace the metal tube back to the front of the engine and remove the large 22mm nut. You may need some penetrating fluid to help loosen this nut. The EGR tube then pulls out of the intake manifold.              
  5. Start cleaning by using a pick to remove some of the carbon from where you removed the EGR tube. There’s a bunch of gunk in there but it’s not easy to clean so do what you can.

  6. Spray some of your degreaser inside the EGR tube and let sit while to start loosening up the carbon buildup while you clean the EGR valve.

  7. Disassemble the EGR valve. Remove the four screws from the plastic section. The two halves should separate. These screws strip extremely easily, use care to not damage them and be sure to keep track of the gasket.
  8. You will now have access to a plunger. This is what opens and closes the EGR valve. Push it to help you clean around the valve. Use the picks, degreaser, and whatever else you need to remove as much carbon as you can. Focus especially on the areas around the valve. Ensure it has smooth operation and can fully open and close. Take your time here.          

  9. Using the round brush, degreaser, and picks, clean the EGR tube as best as you can. I found the majority of the carbon was located toward the end with the 22mm nut. Take your time, once again, you don’t want to have to redo this.

  10. Reassemble everything. Ensure you reconnect all hoses, reconnect all electrical connectors, use all gaskets, and tighten all bolts. Add coolant to your reservoir until you reach the max line.

You should now have a squeaky clean EGR system! Start up the car and check for any leaks or strange noises.

Now if you’re like me and had to clean the EGR system for emissions, you will need to complete a “drive cycle” to pass. All the sensors for the emissions system have to run tests to ensure that they are operating correctly. Since you had the battery unplugged, the sensors have basically reset and need to run all of the tests again. In most states, there is a limit to how many sensors can read “not ready” and still pass emissions. Guidelines to reset most if not all of the sensors are as follows (sourced from MSF):

  1. Before you start to be sure you have: no CELs, fuel level between 15-85%, all accessories off, cold engine.
  2. Start and idle for 5 minutes.
  3. Rev engine in neutral to 2300-2700 RPM for 15 seconds.
  4. Rev engine in neutral to 3800-4200 RPM for 15 seconds.
  5. Idle engine for 20 seconds.
  6. Accelerate to 52-55 MPH, maintain speed in 6th gear for 1.5 minutes.
  7. Decelerate to 15 MPH, drive for 13 minutes at speeds between 15 and 35 MPH.
  8. Drive at 25MPH for 50 seconds.

This order of steps activated all but one of my sensors, meaning that in Washington State I was able to pass emissions in my 2007 Mazdaspeed 6.

Hopefully, this will help out a few of you that are stuck with an EGR system. This procedure saves a few hundred dollars over replacing the valve, making that next modification happen just a little bit sooner!

If you have any additional tips or tricks be sure to share them in the comments, we’d love to hear your experiences!

 

Daniel

CorkSport Engineer

Don’t Be That Noob Guy!

Don’t Be That Noob Guy!

Herrrrrro CorkSport family! This is Luke blogging for you from CorkSport HQ.

I was out doing some logs about a week ago for my tune, and my Mazdaspeed3 started to not boost the way that it should. So I got curious, popped the hood, and found something I normally wouldn’t discuss publicly, yes it’s a bit embarrassing, but hopefully, it will help prevent future issues for someone else.

Before I ruin my reputation with this, I wanted to make sure and point out that everyone makes noob mistakes, and I wanted to bring some of these to light. Perhaps with the only outcome being a good laugh at my expense, and perhaps a learning experience on Mazda troubleshooting for the token few.

Dipshit Dipstick:
Well, here it ladies and gentleman. I had not fully put my dipstick back into the tube the last time I had checked my oil, and when the car started to make all the boosts, the dipstick popped out and shot engine oil all over the engine bay. Not only is there a chance of hot oil igniting in the hot engine bay, but engine oil on top of the block is a pain in the ass to clean off. So here I was with oil all over my engine, and the decision was made to go to the car wash to clean it off.

Don’t Be That Guy – the “Dipstick Dipshit”!

So after experiencing that noob mistake, I decided that anyone who is new to the Mazda platform might need a few “Don’t be THAT GUY” tips and tricks from CorkSport’s team and customer stories. Would love to hear yours if they’re not included… I’m well aware this isn’t an exhaustive list of Noob Mistakes.

Gap Bigger Than The One In My Teeth:
When you start modding a car to make more power, there will always be something that needs to be added to run well. In this case, the noob (anonymous to protect reputation lol) had bought a set of NGK spark plugs under the assumption they came pre-gapped. Slapped them in the Mazda, went to do logs, and the car started to stutter under wide open throttle. Pulled the plugs to realize the plugs that were thought to be pre-gapped… weren’t. They were .044 when they should have been .026. The lesson here is always to make sure and check your gap. Don’t Be The Guy With the Gap!

No Soldier Left Behind:

Have you ever worked on your car, and then six months later find a nice surprise in the engine bay? It happens around the CorkSport Design Shop when we have too many hands on the project. We have all been there, where you popped the hood of the Mazda, only to see that you had left a nice 10mm socket in between the coil packs, or a socket head just under the hood.

I have even lost a pair of pliers; to find them about a year later stuck to the hood latch. The only time I have ever left a tool in my engine bay, and not forgotten about it was when the hood would not latch properly, which is a good indication you’re leaving a soldier behind. That forced me to find out what was wrong. Don’t Be That Guy That has a Tool Set Under The Hood!

Drinking Jose When It Should Be Patron:
When driving a performance enhanced Mazdaspeed, we all need to make sure and feed our ladies with the best type of liquids. When we don’t do that, the women can become upset and not drive properly, and they’re not quiet about it that’s for sure. I have never personally made the mistake of giving my girl the wrong type of liquid, but I have seen it happen before.

Make sure to get all the quality fuels! Don’t Be That Guy That’s Too Cheap To Pay for Good Drinks!

Just remember that everyone makes mistakes, however, just as long as you keep these things to yourself then you will be fine ☺ Just kidding, but really, now that you know… don’t make these silly noob mistakes!
Cheers,
Luke

Winterize – Dear Car Guy

Dear Car Guy,

It’s beginning to look a lot like WINTER, and for those of us who aren’t so lucky to have a daily driver, it’s time to start to winterize our Mazdas.

If you’re not one of those who put their Mazda baby to sleep for the long winter months, check out the tips below to best prepare for winter driving, and keeping yourself safe!

CHECK YOUR TIRES!

• Consider getting snow tires. If you live in an area that gets a lot of snow, swap out your regular tires for all-season tires or snow tires. Seems obvious, but snow tires have a softer rubber that allows them to retain flexibility in the coldest of weather. They also have specifically-designed tread pattern for gripping in ice and snow. They aren’t guaranteed to keep you from slipping and sliding in your car, but they help with better traction. (In winter, any extra help to keep us from losing control of our Mazdas)

• Check the tire pressure. If you’re not opting for winter tires, check your tires often and keep them properly inflated, however this is needed for all tire types. Cold weather changes the air pressure in your tires and causes it to drop (No, it’s not the local kids deflating your tires… I’ve fallen for that one before). Remember that properly inflated tires keep better contact with the road, and while you can’t always keep from slipping, you can do your best to have more connection to the pavement.

• Check the security of your mudflaps. Mudflaps can help keep road debris from killing your paint, be sure yours are securely installed on your ride for maximum protection. If you don’t have them yet, we can hook you up with a fresh set of mudflaps here.

CHECK YOUR FLUIDS AND ENGINE!

• Fill your wiper fluid and change out your blades. Remember that seeing the road is a requirement to staying on it! An ample supply of wiper fluid and new blades will give you a good line of sight in those nasty winter storms. Be sure to use the wiper fluid that has a lower freezing temperature. Otherwise, you’ll be trying to clear your windshield and failing.

• Get an oil change. For your Mazda’s engine to run, it needs the correct oil lubrication. Unfortunately, colder temperatures reduce the effectiveness of the oil. The colder it is outside, the thicker the oil gets. Thickened oil has trouble circulating through your engine, which means your engine doesn’t get appropriately lubricated during startup. Check the owner’s manual to see what oil is currently used in your Mazda, as well as, the recommended viscosity (thickness of the oil) level for different climates.

• Check your anti-freeze mixture. The ratio of your water to anti-freeze mixture should be 50:50 to prevent your radiator coolant from freezing. If you’re unsure, your local auto parts store should have a relatively cheap anti-freeze tester.

• Check your belts and hoses. Colder temperatures potentially weaken the belts and hoses. Look for signs of wear, and replace if needed. In the scenario that a belt snaps while you’re driving, you’ll have to wait for a tow truck, or that trusted buddy to get you out of the cold.

PROTECT YOUR CAR!

• Remove vulnerable exterior mods. Exterior modifications like front lips, custom wheels, and any other exterior bolt-ons that you cherish should be removed. The elements will take their toll on your car, even if it’s parked in the garage at night. From salt on the roads to new potholes you can’t see in the rain, keeping these beloved mods in the garage for the season will preserve your investment.

• Install floor mats. If you don’t already have floor mats in your ride, putting them in the front and back of the car will help keep your interior carpet pristine. Floor mats are easier to clean and can be removed to wash if the mud or snow gets too intense. Click here to check out our CS floor mats.

• Secure your Seat Covers. If you don’t have them, winter is the best time to use them! If you do, make sure that you have them securely installed. The wet from rain and snow isn’t great for the interior and seats. They’re also great for protecting your back and passenger seats from corners of boxes or crockpots of chili while carting presents and food from place to place.

PROTECT YOURSELF!

• Stock your car with emergency supplies. This is one that my dad never let me leave home without. Snacks, blankets, towels, waters, and emergency/first aid kit should be in your trunk during the winter seasons (if it’s not always in there). You never know where or when you might get stranded during winter, and if it’s for longer than expected being prepared is key! Also, the towel is great for kids, passengers, and pets who might be a little muddy or wet from the weather.

Note here from CorkSport: Keeping spare cash in your emergency kit can often help if you’re financially strapped and need to pay for a tow. It could save your butt one day (I know it has saved mine in emergencies!).

• Check your emergency supplies. Road flares, jumper cables, and first aid supplies should be checked for expiration and usability. Road flares do not always have expiration dates. However, the summer months with high heat can sometimes render them unusable (storage above 120 degrees for longer than a week should be avoided), as well as they could be expired if you got your kit for Christmas from Grandma a few years ago.

Whether you’re driving a Mazdaspeed 3, Mazdaspeed 6, or you’re riding around in a Mazda 3 or Mazda 6, we hope that you use our tips to keep yourself safer this winter!

We also sincerely hope that you’re not trying to weather any storms in a Miata or MX5… our Mazda enthusiasts are awesome, but that’s just a different level of crazy!

Anyone else have some good tips or tricks for winter driving in your Mazda or Mazdaspeed?

Share your thoughts or tips in the comments; I am sure we could all use them!

Wishing you safety, warmth, and clear weather this winter!

Cheers,
Kim@CorkSport

 

Kill The Nannies

Nannies. One thing we have discovered while racing our Mazda 3 is that the OEM safety systems in the newest generation of Mazda 3 work well, too well in fact for racing.

Each year, new safety features are added by Mazda which make the cars safer and reduces the risk of collisions. This is great for day to day driving and commuting, but it presents a problem if you plan to take your car to the track to race it.

The OEM system in the car really frowns on lifting a rear tire off the ground, or when you get wheel spin accelerating out of a slow speed corner. They design the cars against these things happening for safety purposes (understandably). However, Mazda does give you a button on your dash to turn off the traction control. This gets us racers around the limitations to a certain degree.

Let me explain:

When you disengage traction control, the system which measures yaw/pitch and ensures your car has all the wheels on the ground is actually still working, even with the button off. What the button does essentially is give you a sort of leash with more leeway, until the computer thinks you have gone too far of course, then it will kick in traction control again.

So, how do we get past these nanny systems so we can push our cars for maximum performance?

Can you simply unplug the computer which controls the this? I wish it were that simple, but you cannot. The systems in the car are all tied to each other, and the car may not start, it may not run safely, or it may run in a limp mode. A good example of this in our 2015 Mazda3 is: if you unplug the rear view mirror the car won’t start. The ABS is also controlled by the same unit, and this is very handy to have on the track.  The ABS is very good in the Mazda3 by the way, so I recommend you keep it.

The solution we’ve come up with at CorkSport is pretty simple: Leave the computer plugged in and turn it over.

That’s it, simple, nothing else is required. What happens when you turn the computer upside down is the computer loses its physical reference point, so it defaults by turning off the stability control and nannies, but most-importantly, the ABS still functions.

A big word of caution: The computer which controls the nannies also runs the airbags. If you race your car on the track, the airbags will have been removed from your car already. DO NOT drive your airbag-equipped car with the module flipped over.

The reason this solution works for the track is that our Mazda 3 race car has additional safety equipment installed, with the 6-point harness and halo seat, along with the rest of the driver’s safety gear, that keep you from injury in the event of any wrecks.

FYI: When using this “hack”, your Mazda 3 dashboard will light up like a Christmas tree from all of the warnings; but that is a small price to pay for the improved performance while racing.

–Derrick

DISCLAIMER: This modification is for racing purposes ONLY. Doing so will render many of your car’s safety systems ineffective. Installing other safety systems after this modification is essential.

 

Beginner’s Dictionary to Mazda Mods

Mazda driving down a road.
Always street tune with a buddy for safety. (PC: renson_ms3)

Everyone was a beginner at some point. Whether you’re new to Mazda modding or you’ve been doing it since you first got behind the wheel, you’re bound to run into some terminology that goes over your head.

At Corksport, our customers are family, and we love learning from and educating our family when it comes to Mazdas. The more you know about your Mazda, the better it can be. This terminology cheat sheet of Mazda language will help you talk the talk as you work to reach your modding goals.

Mazda terminology you need to talk the talk

Axle Back Exhaust: An axle back exhaust starts from the area of the rear axle and extends to the rear bumper. An axle back exhaust replaces the muffler, tips, and a portion of piping that connects to the mid pipes. It has the least effect on performance and fuel economy of all exhaust mods.

Built Block: A built block is a term used when the engine internals are upgraded with higher performance variants over OEM. In most common cases a built block is referred when both the connecting rods and pistons have been upgraded for more strength.

Camber Kit: A camber kit usually consists of a rear camber arm and front camber plates. In addition to correcting wheel alignment on lowered vehicles, a camber kit provides camber adjustment for tracked vehicles which require a slightly negative camber. Correcting the camber is important for even tire wear and maximum traction.

Cat Back Exhaust: A cat back exhaust begins at the end of your catalytic converter and goes all the way back to your rear bumper. It is made up of a rear-pipe, resonator, and muffler. A cat back exhaust system can provide more power, increase fuel efficiency, and deliver distinct sound.

CorkSport cat back exhaust.
Mazda MX-5 with cat back exhaust. (PC: jdm.chris)

Cold Air Intake: A cold air intake essentially lets your engine breathe. Cold air intakes move the air filter outside of the engine compartment so cooler air can be sucked into the engine for combustion. Cooler air brings more oxygen into the combustion chamber and that means more power.

Dyno Tune: Dyno tuning is a systematic approach to engine tuning, allowing a high-quality precise tune-up. During a dyno tune, the vehicle is stationary in a controlled environment.

Front Mount Intercooler: A front mount intercooler cools the charge air from a turbo or supercharged car. Mounted on the front of a vehicle, this intercooler results in better airflow and a higher cooling efficiency. Hot air enters one side and cool air exits the other.

Front mount intercooler on Mazda.
Kyle Sousa’s Mazdaspeed3. (PC: Kyle Sousa)

Lowering Springs: Lowering springs improve the appearance and handling of a vehicle. By lowering the center of gravity on the car and winding the coils closer together, a lowering spring can make the car feel more connected to the road for better cornering. Lowering springs will also give a more aggressive-looking stance and reduce the vehicle’s fenderwell gap.

Mod: Mod is short for modification. Mods are usually performed to enhance the performance and appearance of a vehicle.

NATOR: NATOR is a group of Mazda enthusiasts who come together to share knowledge about their beloved cars. As the story goes, it all began when a few guys got together to work on their Mazdas while enjoying Wendy’s Baconators. BacoNATOR. We can’t make this stuff up.

Join a NATOR near you.
NATOR group doing their thing.

OEM: Original equipment manufacturer.

Oversteer: Oversteer happens when the rear tires reach their limit before the front tires while cornering, leading to the tail opening up.

Powertrain Control Module: A powertrain control module, commonly called a PCM, is the onboard computer of a car. Essentially the brains of the engine control system, it controls many components of a vehicle and is used for diagnostics.

Short Ram Intake: A short ram intake, also referred to as an SRI, is a mod for internal combustion engines. It consists of a short metal or silicone pipe and a conical air filter inside the engine bay. A short ram intake increases power by eliminating the resonator and filter box, giving the air a shorter travel distance.

Short Shifter: A short shifter changes the geometry of the shifter so the distance of the shift lever is reduced. It moves the pivot point higher up the shift rod causing you to move the shifter less distance, with a shorter throw, transforming the driving experience.

Street Tune: Just as it sounds, a street tune or road tune happens on the street. It should be done to maintain the driveability of the system after the top end has been addressed on the dyno.

Sway Bars: A sway bar, also called a roll bar, anti-sway bar, or stabilizer bar, is a part of the suspension that helps reduce the body roll of a vehicle during fast cornering or when driving over uneven road. It connects opposite wheels together through short lever arms linked by a torsion spring.

Understeer: Understeer is when traction is lost at the front wheels while cornering, forcing you wide on a bend despite applying the correct steering angle. If your car is understeering, your speed is not at its maximum and you’re missing the line.

Want to add to our lingo list? Hit us up on Facebook or Instagram and let’s hear it!