Second Hand Vauxhall Astra Glow Plugs

Glow plugs only exist on diesel-engined Astras — they are the diesel equivalent of spark plugs, helping the combustion chamber reach the right temperature for a cold start. Petrol Astras do not have glow plugs at all, so if your Astra runs on petrol you will not find this part on your car. Diesel variants across all Astra generations from the F (1991–1998) through to the K (2015–2022) were fitted with glow plugs, so if you have a diesel engine you are looking in the right place.

The Astra H ran from 2004 to 2010 and the Astra J from 2010 to 2015, so a 2009 and a 2012 car sit in different generations with different engine families — glow plugs from an H are very unlikely to cross to a J. The correct glow plugs are determined primarily by the engine code, which you will find on your V5 or via a VIN check, so supply that code to the breaker rather than relying on year alone. Never assume fitment across a generation boundary without the breaker confirming against your specific engine code.

Trim level makes no difference whatsoever to glow plug fitment — Design, SRi, Elite, Sri VX-Line and other trim grades are purely about interior and exterior specification, not the engine internals. What matters is that both cars share the same engine code; if they do, the glow plugs are interchangeable regardless of which badge is on the tailgate. Confirm the engine code with the breaker against your registration to be certain.

The Astra J ran until 2015 and the Astra K launched in 2015, meaning a late J and an early K could potentially share engine codes depending on which diesel unit is fitted, but the generation changeover means this is not guaranteed. Engine codes are the deciding factor here, and some units carried across while others did not, so this is exactly the kind of cross-boundary question to put directly to the breaker with both registration numbers. Do not assume fitment without the breaker checking both engine codes against each other.

A diesel Astra has one glow plug per cylinder, so a four-cylinder engine has four glow plugs in total — the most common configuration across Astra diesel variants. It is generally recommended to replace all four at the same time rather than a single plug, as the others will be of similar age and wear, and a mismatched plug can cause uneven starting performance. Ask the breaker whether they can supply a complete set from a matching engine to keep your plugs consistent.

Yes, engine displacement and engine code both matter — a 1.7 CDTi and a 2.0 CDTi are entirely different engine families and their glow plugs are not interchangeable. The engine code (for example Z17DTH or A20DTH) is more precise than the badged capacity and is the single most useful detail you can give a breaker when requesting a quote. Check your V5 or run a VIN check to confirm your exact engine code before contacting dismantlers.