This 2009 Ford Focus 1.8 diesel, had been starting without issue all through the coldest weather. When the mornings were becoming a little milder, things were taking a downturn. The engine needed cranking a lot more than it used to. Although most people realise that the glow plugs are essential in winter, warming up the cylinder to allow the mixture to combust, they are also needed, even when the ambient temperature becomes a little higher.

Easily accessed on this engine, I removed the connecting feed wire to the glow plugs and used the ammeter to check the resistance of each plug. Three out of the four did not pass the test, and as these are more old school glow plugs, not the more expensive type often used now, I decided that the best option would be to replace all four.

The old standard size glow plugs do not normally encounter the same problems when removing then that the newer pencil type can, but taking precautions, I warmed the engine and allowed the threads to have a soak in penetrating fluid before attempting the removal.

The job went smoothly, and the new glow plugs were soon in place and connected up again. The proof of the pudding would, of course, be in the way the engine started the next morning, but I was quite confident that this Ford’s starting problems were over.

You can download this story as a PDF, as well as other technical tips at TechTips.ie.

There are lots more Tech Tips to view, and they are all searchable, on TechTips.ie.