A clean sweep
A faulty exhaust gas recirculation (EGR) valve can cause all sorts of running problems with your vehicle, as you’ll read in our feature starting on page 6. Most of us will only remove and examine an EGR valve when a fault code has appeared, indicating that it’s not operating as intended. However, you can often avoid unnecessary breakdowns by simply cleaning the valves regularly, either in situ or by removing them from the engine.
On some engines it is wise to remove the EGR valve at every service to keep it in as clean a condition as possible. If your vehicle is garage-serviced, most likely the mechanics won’t go anywhere near the EGR valve unless you instruct them to clean it – it’s just not part of any service schedule. However, if you are doing your own servicing, then some preventive maintenance of the EGR valve is a wise and cost-effective move.
When my partner, Sarah, informed me that her father’s 2004 Mazda3 1.6 petrol had an illuminated Malfunction Indicator Light (MIL) and the garage was saying it was Egr-related, I went along to see what I could do. To cut a long story short, I removed it for a clean-up, using a dedicated cleaner and Sarah’s toothbrush (shhhh, don’t tell her!) to really get into all the port holes. Refitting the valve, clearing the fault code and running the engine, it took about five miles for the MIL to come back on. So it was off with the EGR again, this time cleaning it with Wynn’s Petrol EGR Extreme Cleaner. I let the valve dry, refitted it and it lasted a bit longer this time before the MIL came back on. Time for a replacement?
I purchased a secondhand EGR, fitting a valve from a Mazda MX-5 (the part number is the same as the Mazda3 unit and it increases your chance of finding a bargain). Bought for £19.99 (inc p&p) off ebay, it was attached to the engine in no time – the MIL has remained unlit ever since – that was in 2017!