Ignition Coil UF89 30500-PT2-006 for Honda Civic Accord

Honda 30500-PT2-006, better known as UF89, is the coil that took Honda from a distributor to a wasted spark ignition on the D and B series engines of the nineties, and it is still one of the most common coils in the aftermarket because so many Civics, Accords, CR-Vs and Preludes used it. It is a block mounted coil, not a pencil coil: a rectangular body with two towers that feed paired cylinders through short HT leads, mounted on the end of the cylinder head or on the intake side depending on the model.

Inside there are two separate windings, one for each tower, driven by an external igniter on most applications, which is why the coil has a multi pin connector with a tachometer feed as well as power and trigger. The body is potted in epoxy and the towers have deep recesses with a spring contact inside. Because each tower fires two cylinders, one on compression and one on exhaust, the coil fires twice as often as a single cylinder coil, and the insulation has to cope with twice the thermal cycles.

The symptom that brings most owners here is a misfire that appears when the engine is hot, often after a motorway run, and disappears once it cools. Cracks in the potting compound open up when hot and the spark jumps to earth inside the coil, killing two cylinders at once, so the engine runs on two and shakes badly. A P0300 or a pair of codes such as P0301 and P0304 together is the giveaway for a wasted spark coil. The towers also carbon track where the HT leads have been pulled off by the wire rather than the boot, and that track will short a new coil if the leads are not replaced.

Unplug the connector, pull the two HT leads out by their boots, undo the mounting bolts and lift the coil off. Check the leads for cracked insulation and for corrosion in the towers, and renew them if there is any doubt. Fit the new coil with the towers clean and dry, push the leads in until they click, and make sure the earth strap or mounting surface is clean because the coil earths through its body on some versions. Clear the codes and run the engine until the cooling fan has cycled twice before a road test.

Supplied as one coil. Twelve month warranty.