Car Diagnostics | Book a Car Diagnostic for your Porsche

Trustpilot rating for all RAC Mobile Mechanics.

Why choose the RAC for a car diagnostic?

With RAC Mobile Mechanics, you can avoid the hassle of taking your vehicle to a garage. They can do a vehicle diagnostic check on your driveway, so you don't even need to leave the house.

When it comes to diagnosing issues with your vehicle, our friendly expert mechanics are here to help. We use state-of-the-art diagnostic equipment to accurately identify any problems, ensuring your vehicle runs smoothly and safely. The price includes the diagnostic service – no hidden costs. Just friendly, honest experts.

Close up of an RAC Mobile Mechanic underneath a car

Our top pick for your Porsche

We’ll come to you at home or work

RAC Mobile Mechanic for your Porsche

At the RAC, we’ve got over 125 years’ experience in offering complete peace of mind to our members. We’re best known for our breakdown service. And now – our new RAC Mobile Mechanics are here to help make every day motoring easier. If you need a service or repair, they’ll come to you at your home or work.

Book a car diagnostic

For a limited time, get £50 off repairs over £150 when you book a diagnostic test. Offer ends 09/12/25, 09:00.^**
Our mobile mechanics will spend up to 30 minutes checking your car for faults and talk you through any repairs you might need and give you a report for your records.

OEM quality parts

We use original equipment manufacturer (OEM) standard parts, which means every new part will be the same standard and same quality as the original part it replaced.

Mechanics you can trust

Our mobile mechanics are friendly, honest, and backed by the RAC.

Close up of an RAC Mobile Mechanic running a vehicle diagnostic check

Book a repair

It’s easy to book a car repair online. We bring the garage to you with RAC Mobile Mechanics, or find a trusted local garage. Common repair jobs include:

Clutch Replacement

We diagnose and repair clutch issues – whether your clutch is heavy or slipping, or you’re having trouble changing gears.

Alternator repair

We check and correct alternator faults to keep your charging system running smoothly.

Oil change

Oil is vital to a healthy engine, so it’s important to change it regularly.

Brake pads & Discs

If your brakes are making noise or you’re noticing reduced stopping power, it’s likely time to replace your brake pads or discs.

And it’s not just car diagnostics that we do for your Porsche

Mobile mechanics bring the garage to you, saving you the hassle of getting your car to a garage. If you need a service or repair, they’ll come to you at your home or work.

A close up of an RAC mobile mechanic looking under the hood of a car

Try one of our RAC Approved Garages

View all garages

RSC Ltd.

4.5/5

We have on site a fully equipped three ramp workshop. Our work shop philosophy is very old school, we will never carry out any work to your vehicle unless it is needed, always ask your permission to carry out any work up and above what has been agreed and do our utmost to give a fair and reasonable cost service at all times. As a result of this we have a loyal database of customers from Rickmansworth, Watford, Northwood, Hatch end, Bushy and surrounding area. We offer a wide variety of services at an extremely competitive rate especially when compared to the main dealers, these include: servicing, repairs, bodywork, tracking, tyres, air conditioning re gasses, clutches, brakes, exhausts, car audio and alarms.

Oxhey Drive, South Oxhey, Watford, WD197SE

LM MOTOR CLINIC

4.8/5

Welcome to LM Motor Clinic in Kilmarnock. We are a long-established well run Castrol Service Centre providing exceptional garage repair services all provided by fully qualified and experienced technicians at competitive prices. Based in Kilmarnock, whether you need servicing, repairs or even diagnostics we can help. Our technicians have over 30 years combined experience in the motor industry so you can always rely on LM Motor Clinic for first-class servicing and repairs. What We Can Offer: Car & Van Servicing & Repairs Tyres & Exhausts Clutch Replacements Diagnostics Oil Changes Breakdown Recovery Castrol service Centre Flexible Payment Options As well as the above we also provide our customers in Kilmarnock with the following, Fair and Friendly Service, Pick Up Drop Off Service & all our garage services are Competitively Priced making sure you get the best possible rate for your service. Find out how we can help you Quality Work Honest Pricing Exceptional Customer Service Complete Peace of Mind We Have the Lastest Diagnostics with Dealer Software. Voted Scottish Garage of the Year and Scottish Specialist Garage of the Year at the Scottish Garage awards

19 Dean Street, Kilmarnock, KA31DY

MK MOT & Service Centre

4.8/5

We are a local independent garage offering our customers all forms of mechanical repairs, servicing and MOT's. Business partners Mark and Craig have over 50 years' experience working on all makes and models of vehicles, with no job being too big or too small. We are members of the Institute of the Motor Industry (IMI) which should offer you peace of mind that we take great pride in our work as it ensures we remain up to date with all courses and techniques. We work out of a large workshop which has 4 ramps, including an MOT bay, and we have a large comfortable waiting area available for your use should you like to wait whilst we work on your car.

36 Barton Road, Eaton Ind Est, Milton Keynes, MK23LQ

California car and commercials Ltd, Bosch Car Service

4.4/5

We are a established MOT and service centre run by two brothers with a combined experience of 15 years in the motor trade. Our new site on Garrard Way, Kettering consists of 5 service bays and a class 4, 5 & 7 MOT bay. Our aim is simple, to be a one stop shop for all your motoring needs. Wether it be your annual MOT and service or more major work our highly experienced staff are on hand to help. We have a clean, modern premises with state-of-the-art technology and equipment including the most up to date Snap-On class 4, 5 & 7 MOT bay. We run our own fleet of recovery vehicles so collection and delivery is always available. Feel free to call Tony or Mario for any of your vehicle needs

Garrard Way, Telford Way Industrial Estate, Kettering, NN168TD

Diplock Fuel Injection Services Ltd

5.0/5

We at Diplock Fuel Injection Services Ltd are a professional and friendly company based in Hailsham. Established since 1985, with individuals having over 50 years experience our car mechanics offer an array of car maintenance services. We specialise in diesel fuel injection and MOT testing, and can offer a comprehensive selection of repair work. We have built up a highly sought-after reputation and we come highly recommended by people in the trade. We also pride ourselves on offering very good rates on MOT tests; so please contact us for an unbeatable price!

Unit 3/4 Avocet Way, Diplocks Way, Hailsham, BN27 3JF

Frequently asked questions on car diagnostics

How much does it cost to diagnose a car problem?

The cost you pay can vary depending on the type of car and how complicated the diagnostic test. Check with your mechanic for a quote.

Is a car diagnostic test worth it?

Yes, a diagnostic test may save you a lot of money. It finds issues early before they become costly repairs. It can also keep your vehicle running efficiently and safely

Can I do a car diagnostic myself?

While you can buy a diagnostic tool, interpreting the results needs expertise. It’s best if you to have a professional mechanic perform the test.

How long does a car diagnostic test take?

Diagnostic tests take from 30 minutes to a few hours. This depends on what issues are being looked at.

What are common car diagnostic codes?

Common diagnostic trouble codes include:

P0300: Random/Multiple Cylinder Misfire Detected
P0420: Catalyst System Efficiency Below Threshold
P0171: System Too Lean (Bank 1)

These are general examples, so your car may have different codes. Always check with a mechanic so you get an accurate diagnosis.

Is a car diagnostic test necessary for a service?

Yes, they are. Regular diagnostics can help keep your car in good health. It makes sure that underlying issues are addressed quickly, so you can drive with peace of mind on the road.

Again, keep in mind that mechanics might have their own checklists. Chat with your mechanic to be sure that they address any specific issues you have.