Parts for your 2013 Holden Colorado-Ignition coils

2013 Holden Colorado ignition coils — are they even a thing?

For Australian and New Zealand models of the 2013 Holden Colorado (RG series), ignition coils aren’t fitted or required. These utes came with the 2.8‑litre four‑cylinder turbo‑diesel engine, which uses compression ignition rather than spark ignition. That means there are no spark plugs and no ignition coils on these vehicles. Instead, they rely on high‑pressure common‑rail fuel injection and glow plugs to aid cold starts. This isn’t guesswork: the Holden RG Colorado Owner’s Handbook (MY13 AU/NZ) points to diesel‑only fitment and details a glow plug indicator, and the GM Holden RG Colorado service information for the 2.8L turbo‑diesel lists no ignition‑coil service procedures. VM Motori’s A428 engine documentation (the base engine design) and Bosch literature on common‑rail diesel systems both describe why diesels don’t use coils at all.

Why no coils? In a diesel, the air is compressed until it’s hot enough to ignite fuel as it’s injected—no spark needed. So the “ignition” system in a diesel is effectively fuel delivery timing and pressure, not a high‑voltage spark event. Glow plugs and their control module help with cold starting, but they don’t replace ignition coils, they’re simple heaters, not spark makers.

If the Colorado feels like it’s “misfiring,” think diesel: issues are more likely with injectors, fuel quality, a clogged fuel filter, intake leaks, EGR or boost problems, or a lazy glow plug causing rough cold starts. That’s where servicing attention should go—regular fuel filter changes, clean air filtration, checks on injector performance, glow plug testing, and making sure the battery and charging system are healthy for strong cranking.

It’s worth noting that some overseas Colorados/Isuzu D‑Max relatives had petrol variants that do use ignition coils, but that wasn’t the case for AU/NZ in 2013. So if someone’s shopping for “ignition coils” for a local 2013 Colorado, they’re looking for a part the ute simply doesn’t have.

• Technical sources referenced: Holden RG Colorado Owner’s Handbook (MY13 AU/NZ), GM Holden RG Colorado Service Manual (Engine — 2.8L turbo‑diesel), VM Motori A428 engine technical data, Bosch Common‑Rail Diesel System overview.

Popular questions about 2013 Holden Colorado ignition coils

Does a 2013 Holden Colorado have ignition coils?
No. The AU/NZ 2013 Colorado is a 2.8‑litre turbo‑diesel and doesn’t use spark ignition, so there are no ignition coils or spark plugs. It uses glow plugs for cold starts and a common‑rail injection system to deliver and control fuel.

What causes “misfire‑like” symptoms on a diesel Colorado if there are no coils?
Rough running, hesitation or a shudder is usually down to fuel‑system or air/boost issues—think a dirty fuel filter, poor‑quality diesel, a weak injector, intake/boost leaks, EGR fouling, or sensor problems (MAP/MAF). On cold starts, a failing glow plug or control module can also make it stumble briefly.

Do glow plugs need regular replacement on a 2013 Colorado?
They’re not a scheduled “every X kilometres” item, but they do wear. If cold starts get slow, the glow-plug light misbehaves, or there’s rough idle only when cold, have them tested. Many techs replace the set once one fails, using OEM‑spec plugs and following proper torque and battery‑off procedures.