Got An EGR (Engine Gas Recirculation) Issue? Is The EGR Clogged Up? Want To Avoid Replacing The EGR Valve?

Our diagnosis and 3-step engine carbon cleaning is your best option!

Why does it get clogged up?   The EGR system recirculates expelled exhaust gases, because these gases contain oil residues, carbon from the burnt diesel and other such nasties the valve that controls the amount of gases recirculated, the related pipework, and if fitted a cooler (designed to cool the gases on recirculation) will over 1,000’s of miles become clogged.

This leads to symptoms such as poor engine performance, lowered fuel efficiency, engine management warning lights and the limp-home-mode being activated (restricted performance), lowered fuel economy, rough idling and/or a strong fuel odor. We have a great wealth of knowledge and specialise in the diagnostics and cleaning of the EGR system. This includes live data analysis using dealer level diagnostics equipment that we include in all our EGR cleaning services.

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How do we clean the EGR?   Firstly we’ll use our dealer level diagnostics equipment to assess the engine management error codes and complete live data analysis. Then assuming the vehicle is fit for cleaning we use a 3-stage carbon cleaning system that includes our world-leading Hydrogen carbon cleaning and our unique chemicals. This means in the majority of instances there is no requirement to remove the EGR for cleaning and assuming it’s just clogged up / dirty this will resolve the issue. On completion of the job, which takes approximately 45-60 minutes, we’ll reassess the engine management system and reset any fault codes.

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3-Stage Engine Carbon Cleaning

Citroen C3 EGR Carbon Cleaning With Client Review

EGR Cleaning Options

Choose The Best Option For Your Vehicle

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1-stage Carbon Cleaning

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Our world class Hydrogen generating machine pulses Hydrogen and Oxygen into the engine which upon contact with dry hardened carbon will burn it back into it's hydrocarbon state (a gas) so that it can exit safely through the exhaust system. Includes FREE dealer leval diagnostics scan.
For more information please view How Carbon Cleaning Works

Recommended for: Those who use our Carbon Cleaning Services annually or every 10,000 to 12,000 miles.

Price: £89.99 - £119.99

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Hydrogen Engine Carbon Cleaning
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3-stage Carbon Cleaning

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This service is based on stage-1 Hydrogen cleaning but also utilises our unique chemicals for a more in-depth cleaning. It also dries out the moisture (mainly oily residues) which restricts the EGR system so that the Hydrogen cleaning can be more effective. This is then topped off with the inclusion of our proprietary injector cleaner to ensure a cleaner combustion thus slowing down the risk of further carbon build up causing repeat clogging.

Recommended for: Vehicles that are suspected of or definitely have EGR failure causing symptoms such as Limp mode (restricted performance) or loss of power, excessive smoke or engine warning lights for the EGR.


Price: £149.99 - £169.99

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Remap for EGR delete and 3-stage Carbon Cleaning

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First we supply our unique 3-stage service as above to ensure a clean engine and system, we then we reconfigure (remap) the vehicle's computer to permanently switch off the EGR system whilst also programming it run more efficiently without it. This solution, which is also known as EGR blanking, is an alternative to the expensive EGR replacement that for most vehicles is 2-3 more costly. As this takes the EGR system completely out of the equation (it's not required for the engine to run correctly) it is also a guaranteed permanent fix that not even replacing the EGR can offer. For further details on this service please call us or speak to your technician upon their arrival.

Recommended for: Vehicles that are suspected of or definitely have EGR failure causing symptoms such as Limp mode (restricted performance) or loss of power, excessive smoke or engine warning lights for the EGR.

Price: £339.99

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Understanding The EGR Valve System

The purpose of the EGR (Engine Gas Recirculation) system is to reduce nitrogen oxide (NOx) emissions that primarily form when nitrogen and oxygen is subject to high heat and pressure. Nearly all modern diesel and some petrol engines require an EGR system to meet emissions regulations. The system is designed to recirculate exhaust gases back into the intake system which reduces either O2 in diesel engines intake stream or combustible matter in a petrol engines intake stream. These gases have little or no ability to react to the second combustion cycle they are subjected to thus helping to reduce combustion heat and in-cylinder temperatures.

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Unfortunately, these recirculated exhaust gases carry a lot of carbon, unspent fuel (including varnishes) and oil vapour which gradually accumulates and bonds as carbon particles inside the inlet and re-circulatory system and especially on and around the valve itself. This leads to numerous engine problems and worst case even engine failure.

The specific purpose of the EGR valve determines if, when, and how much exhaust gases are recirculated. As carbon deposits build up in and around the valve it prevents the opening and closing of the valve operation, and worst case the valve can become stuck losing all functionality.

Usually, the initial driver symptoms of the clogging of an EGR valve are loss of power, excessive black smoke under load, engine management lights, limp mode, and engine stalling, especially when coming offload. Eventually, the valve will stick in either the open or shut position. If stuck open the carbon build-up saturation will be accelerated whilst if stuck shut it will cause excessively high emissions and ultimately MOT and/or roadside emission test failures.

How To Clean The EGR Valve

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There are numerous ways to clean or replace the EGR valve with varying prices.

The costliest option is a complete replacement part and a clean. Most mechanics will recommend this – Why? Because they’ll earn a profit from the part and it’s a quicker job for them. The price of an EGR valve varies on average between £300 and £1,500 plus labour for fitting. At the time of replacement, or just before, it’s important that the rest of the EGR system is also cleaned otherwise carbon deposits within the rest of the system will likely clog the new component.

The moderately expensive alternative is to remove the valve and manually clean it which requires mechanical skill and time. The problem is not all valves are so easy to remove and refit and the outcome may not always be successful. Of course, it’s not just the valve though, there are all the associated pipes and if fitted the cooler must also be cleaned. Expect prices to be anywhere from £200 – £500 for such a job if done correctly rather than just the valve.

Then there’s our service, the most cost-efficient option. Even if the valve has failed and therefore the cleaning doesn’t resolve a valve issue completely at least the rest of the EGR system will be cleaned and ready for a new component which on its own will save you money!

Preventative cleaning starts from as little as £89.99 (for a car)

If your vehicle has an EGR issue, or has even failed an EGR manual clean by a garage, and therefore requires further assistance to resolve the problem there is no better alternative than a skilled UKCC technician providing our 3 or 4-stage carbon cleaning service.

From just £149.99 (for a car). The advantages are:-

  1. Our Mobile Carbon Cleaning Technicians come to you
  2. Potentially no expensive parts
  3. No disassembly is required, therefore no expensive labour
  4. Completed in an average of 45-60 minutes so no requirement to leave your vehicle with a garage for days on end
  5. We are fully insured to complete this service at the roadside or wherever your vehicle is located

Spread the cost over 4 payments

No Interest, No Charges

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Ask for Payment Assist
When you make your booking ask to spread the cost via Payment Assist. If you book online please ensure you call us in advance.

Unless pre-approved we require a minimum invoice value of £250 to take advantage of the Payment Assist service.

*The payment process is subject to approval by Payment Assist

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Processing your application with your technician on the day of the service.
No credit check . Instead a high street bank debit card is used to approve pre payments is required.

PLEASE NOTE: Internet only banks such as Stirling Bank are presently not approved by Payment Assist.

*The payment process is subject to approval by Payment Assist

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Easy payment plan
Upon approval* your invoice is split into 4 equal payments. The first payment is processed on the debit card immediately and you are back on the road. The balance will be split over 3 further monthly payments.

Example: Invoice value £400 divided by 4 = 4 x £100 payments. NO INTEREST AND NO CHARGES.

*The payment process is subject to approval by Payment Assist


Depending on the level of service chosen our engine carbon cleaning service takes a total of 45-60 minutes.

Carbon cleaning is not as such a fix, its original purpose is cleaning as a preventative measure as carbon build-up is the root cause of 85% of the failure of components. If the component is simply clogged with carbon using not just our basic Hydrogen cleaning system but also our proprietary chemicals (that our competitors do not have access to) it is often possible to restore the operation of some components such as an EGR valve. However, if the component has failed then of course cleaning cannot fix something that has already failed. If you have an engine management system fault or a component diagnosis we recommend speaking to your local technician to discuss success ratios and options.

You cannot clean too much but we recommend preventative cleaning once a year, or every 10-12,000 miles – just like a regular oil change but for the air and fuel side of your engine - little and often is the key and as the saying goes… ‘An ounce of prevention is worth a pound of cure!

Certainly not. We are a worldwide brand with CE marked machines, operating in over 50 countries with 100’s of machines being used daily – never has there been an engine damaged from our engine carbon cleaning process.

We would not take any risks with your vehicle, so for piece of mind UKCC Auto Techs guarantee to you that all our technicians are trained to the highest standards and are independently fully insured.

No, this process is totally safe and untraceable.

Yes, we offer multi-service and multi-vehicle discounts.

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