A sticking or carboned-up EGR valve can cause warning lights, rough running, flat spots and limp mode. An EGR delete is a software solution that stops the ECU from using and monitoring the exhaust gas recirculation system. At Mac Tuning we carry out EGR deletes at our Hertfordshire workshop near Stevenage. We supply the software, and it takes 45–60 minutes.
We've tuned over 5,000 cars and have over 300 five-star reviews. Vans, pickups and cars come to us from across Hertfordshire and from all over the UK, and a fair number of them have already had a cheap EGR delete elsewhere that needs putting right.
What does the EGR system do?
The exhaust gas recirculation (EGR) system sends a measured amount of exhaust gas back into the intake. That lowers combustion temperatures and cuts nitrogen oxide (NOx) emissions.
On a modern diesel the system usually includes:
an EGR valve, electronically controlled by the ECU
an EGR cooler to bring the exhaust gas temperature down
on many Euro 6 engines, a second low-pressure EGR circuit after the DPF
position sensors, plus mass airflow and boost readings the ECU uses to check the EGR is doing what it asked
Because the gas going back in carries soot, carbon builds up over time in the valve, the cooler and the intake. The ECU monitors the system closely and will log codes and limit power if it thinks the EGR isn't behaving.
Why drivers choose an EGR delete
The most common reasons people book an EGR delete with us are:
EGR warning lights or engine lights that keep coming back
Limp mode or a sudden loss of power tied to EGR flow or valve position codes
Rough idle, hesitation or smoke linked to a sticking EGR valve
Heavy carbon build-up in the valve and intake, a common issue on many diesels
Tuning. On a Stage 1 or Stage 2 diesel, many customers want the EGR switched off at the same time
A previous EGR delete that hasn't held up (more on that below)
How our EGR delete works
Software, and sometimes physical work too
Our EGR delete is a software solution. Depending on the vehicle, the EGR valve may also need to be physically blanked or disconnected. Mac Tuning provides the software only, so any physical work is carried out separately. We'll tell you when you book whether your vehicle is likely to need it.
1. Your original software is saved
Before anything changes, we read the ECU and save your original software. The software side can always be reversed later.
2. Software set up for your vehicle
Mac Tuning has developed its own software for most vehicles over years of testing and research. Each EGR delete is set up for the specific vehicle and software version. We switch off EGR control and monitoring, and handle the related airflow and position checks properly, so the ECU doesn't keep flagging the system.
3. Checked before you leave
We clear the stored codes and check the vehicle over once the new software is written. The job takes 45–60 minutes.
With EGR deletes, you get what you pay for
Cheap EGR deletes are everywhere, and we regularly put right ones done elsewhere. Common problems we see include:
EGR or engine warning lights coming back
limp mode from airflow or boost codes that were never dealt with
poor running, smoke or hesitation because the fuelling and air mass targets weren't adjusted to suit
only one EGR circuit switched off on engines that have two
other modules still logging emissions faults
Most of these come from generic files, or from software that doesn't match the vehicle. Getting it set up properly the first time saves a second visit.
EGR delete with a Stage 1 remap
As the ECU is already being read and written, an EGR delete is often done alongside a remap. A Stage 1 remap takes 60–90 minutes on its own, and every tune is set up for the specific vehicle. See our guide to a Stage 1 remap in Hertfordshire, or browse our performance tuning options.
EGR delete for BMWs, vans, pickups and any vehicle
We offer EGR delete software for any vehicle fitted with EGR. The vehicles we see most often are:
BMWs, including the 20d diesels (120d, 320d, 520d, X1 and X3)
Vans, including a lot of Ford Transits
Mercedes vans and cars
PSA-group vehicles: Peugeot, Citroen and Vauxhall
Pickups
If yours isn't listed, send us your registration and we'll confirm.
EGR, DPF and AdBlue together
The EGR, DPF and AdBlue systems work together to control diesel emissions, so trouble with one often shows up in the others. See our guides to DPF delete in Hertfordshire and AdBlue delete in Hertfordshire. More than one software solution can usually be done in the same visit.
EGR deletes are intended for off-road and motorsport use.
EGR delete across Hertfordshire
We're based near Stevenage and regularly see vehicles from Stevenage, Hitchin, Letchworth, Hertford, Welwyn, St Albans, Luton, Bedford and Cambridge, as well as cars from all over the UK. You can pay in instalments with Klarna or Clearpay, and you can read what our customers say on the reviews page.
EGR delete FAQs
How long does an EGR delete take?
45–60 minutes for the software. If you're having a remap or another delete at the same time, allow a little longer.
Does the EGR valve need to be blanked?
It depends on the vehicle. On some, the EGR valve also needs to be physically blanked or disconnected. We provide the software only, so any physical work is carried out separately.
Can an EGR delete be reversed?
The software can. Your original software is saved, so it can be reinstated. Any physical work would need to be reversed separately.
I've had an EGR delete elsewhere and the light is back. Can you sort it?
Yes, this is a regular job for us. We set the delete up properly for your vehicle's software rather than adding another patch on top.
Can I combine an EGR delete with a DPF or AdBlue delete, or a remap?
Yes. They can be done in the same visit, and your original software is saved in the same way.
Can I spread the cost?
Yes, Klarna and Clearpay are both available.
Book your EGR delete
Send us your registration and a note of any warning lights or symptoms, and we'll come back with availability. Book online or get in touch to talk it through.
