DENSO is one of the world’s leading innovators and manufacturers of ignition technology, including spark plugs. We were the first company to produce long-life automotive Iridium Spark Plugs, and invented the world’s smallest, most efficient 0.4mm Iridium tip.
DENSO has also developed Iridium CoGeneration Spark Plugs – a unique range of robust, high performing Iridium spark plugs especially for the gas engine industry.
Iridium CoGeneration Spark Plugs combine all the performance benefits of DENSO’s Iridium Spark Plug technology with a number of additional efficiency advantages. Choose from Iridium Saver, and the latest Iridium Saver DDI.
- Highly reliable monolithic resistor. Iridium Saver guarantees high reliability for withstanding high combustion pressures by incorporating a stress-resistant monolithic resistor that adheres to the resistor glass in the high temperature furnace. In addition, this eliminates interference to electronic equipment from high energy coil noise.
- Powder sealing
- Hot lock
- Special Nickel plating with better corrosive resistance; with better corrosive resistance for condensed acid water.
- Reduced maintenance costs
- Extended plug life
- Iridium alloy pad + platinum alloy pad; The Iridium alloy pad (developed and patented by DENSO) is located on the centre electrode. A platinum pad is located on the ground electrode. The two pads help to provide excellent wear resistance compared to conventional spark plugs.
- Dielectrical resistance welding (ground electrode); DENSO achieves superior performance by accurately controlling the welding conditions.
Iridium Saver DDI
- Highly reliable monolithic resistor: Iridium Saver guarantees high reliability for withstanding high combustion pressures by incorporating a stress-resistant monolithic resistor that adheres to the resistor glass in the high temperature furnace. In addition, this eliminates interference to electronic equipment from high energy coil noise.
- Powder sealing
- Hot lock
- Special Nickel plating with better corrosive resistance: Better corrosive resistance for condensed acid water.
- Iridium GE pad with robust welding for high temperature resistance and long life.
- Proven longer plug life: Iridium pads located on both the centre electrode and the ground electrode (hence DENSO Double Iridium - DDI) minimise spark gap expansion, ensuring a longer plug lifetime.
- Double iridium alloy pads: the Iridium alloy pads (developed and patented by DENSO) are located on both the centre electrode and the ground electrode. The two pads dramatically improve wear resistance compared to other Iridium plugs by minimising spark gap expansion.
- Convergence laser welding: wedges created by laser welding fix Iridium alloy pad securely on the ground electrode. Delivers high reliability in high temperature combustion engines.
Identifying DENSO Co-Generation Spark Plug
Installation & Fault finding
Recommended Torque and tightening angle
- Use the correct wrench for the hex on the plug, and be careful not to damage the insulator.
- When changing, make sure that no foreign substance falls into the combustion chamber.
- When putting the plugs in, make sure that all cylinders are clean.
- Make sure the plugs are vertical, then tighten them by hand until they cannot be tightened any further (A+B).
- Then, use a spark plug wrench to tighten them accurately according to the recommended torque specifi cation (C+D).
DENSO recommends using lubricant on the thread.
An effective way of diagnosing the engine’s operating condition is to check if the spark plugs look
abnormal. If all cylinders are operating normally then the spark plug appearance is light grey, there are tanned deposits and there is a slight electrode erosion.