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Portlaoise Diesel  Ltd is owned by Eugene Hearns. Eugene has taken over the business from John Brennan who has retired after 30 years. Eugene has worked with John for the past 15 years and has good experience and knowledge of the industry. We are located on the Timahoe Road in Portlaoise. Co. Laois


We are one of the top Diesel Repairs companies in Ireland. We can test & repair most of the leading diesel injectors and pumps inc Bosch, Siemens, Delphi, Denso. We also stock a large quantity of new parts for any type of Diesel Vehicle or Engines.


We have a dedicated workshop with four fully qualified Diesel Technicians. Our workshop includes technologically advanced state-of-the-art common rail systems and electronic diesel control (EDC) systems for both cars and commercial vehicles

Our injectors are coded where necessary with IMA coding, this is an industry standard which is required allow the ECU to vary fuel accordingly and optimise engine performance.

If you have a question check out our FAQ's first to see if your question is there.

If you need help find your part number or identifying your injectors have a look through our part identifier here.

IMPORTANT: Please note we no longer operate the garage business ourselves. The garage is leased and owned by Laois Auto Care contact them if you wish to bring a vehicle in for diagnostic or repairs 057 8509071


Established in early 2000, our diesel repair center has grown from a tiny one-man show into a thriving national operation 

In the late '70s, John Brennan discovered his passion and talent for innovative diesel performance injection systems and repairing diesel pumps, while under the watchful eye of Tom Cooney now Portlaoise Turbos.


After honing his diesel repair skills, John set up his small repair shop at his house.  Portlaoise Diesel Injection was open for business, though business wasn't exactly booming John sweated out the rough in the early years the only way he saw fit—by establishing innovative diesel performance that saves customers money over the long haul and by providing dedicated, honest service.


Remaining true to those core values to this day. Portlaoise Diesel Injection has earned its place as a leader in the Irish diesel market and later looked to expand on that success. 

The company expanded its workforce to fifteen over the years and in 2012 they moved to a larger premises where business continued to grow. John now had a garage running full time alongside his repair workshop. 

In 2015 John split the garage and injector business and leased the garage out that company was in operation until late 2021. When John took back over for a few months until a successful tenant could be found.

In January 2022 John leased the garage aspect of the business to Laois Auto Care to let John focus on his real passion of repairing the pumps and injectors.

In March 2023 John retired and Portlaoise Diesel Ltd owned and run by Eugene Hearns Jnr has taken over.

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