OEM Auto Distributor Caps

Keep Your Engine Running Strong with Quality Distributor Caps

The Bob Howard PDC parts team has all the parts you're looking for your upcoming restoration or repair project. Distributor caps direct high-voltage electricity from the ignition coil to the correct spark plug at precisely the right moment. These insulated covers sit atop the distributor, containing terminals that connect to spark plug wires. Older vehicles like the Jeep Wrangler TJ and Honda Civic from the 1990s rely on distributor caps to maintain proper ignition timing and smooth engine operation.

How Distributor Caps Route Electricity

The distributor cap houses a rotor that spins inside, making contact with terminals in sequence. High voltage from the coil enters through the center terminal. As the rotor spins, it transfers this voltage to each outer terminal in firing order. Each terminal connects to a spark plug wire, delivering electricity to the appropriate cylinder at the correct time for combustion.

Why Distributor Caps Fail

Moisture enters through cracks or worn seals, causing electrical tracking and misfires. Carbon buildup on terminals creates resistance that weakens spark delivery. The rotor contact point inside wears down from repeated arcing. Heat and vibration crack the cap material, allowing voltage to escape to ground. Generic aftermarket caps often use cheaper plastics that crack easily and inferior brass terminals that corrode faster than genuine OEM components. These low-quality alternatives cause misfires and poor performance that affect your entire ignition system reliability.

When to Replace Your Distributor Cap

Install a new distributor cap if your engine runs rough, backfires, or has difficulty starting in damp weather. Visible cracks, carbon tracking marks, or corrosion on terminals indicate replacement is needed. Most distributor caps require replacement every 50,000 to 80,000 miles as part of routine ignition system maintenance.

Get out of the breakdown lane and back in the fast lane with genuine OEM parts from Bob Howard PDC.