ThunderSpark Distributor Cap P/N:925-1012

Keep high-voltage spark flowing to the right cylinder with the ThunderSpark Distributor Cap 925-1012 (also written 9251012), an OE-replacement cap for vehicles running conventional distributor-based ignition systems. It drops in as a direct-fit replacement for a long list of GM applications, including the 1991-1993 Buick Roadmaster, 1990-1992 Cadillac Brougham, 1987-1994 Chevrolet Blazer, 1988-1995 Chevrolet C1500, 1987-1992 Pontiac Firebird, 1995-1996 AM General Hummer, and many more — see the Buyer's Guide tab for the full list.

The distributor cap directs high-voltage current from the ignition coil to the correct spark plug through the rotor and internal terminals. Over time, caps can develop carbon tracking, cracking, or corrosion that leads to misfires, hard starting, and drivability issues. If a worn or cracked cap is the cause, this unit restores that connection.

• OE-Replacement Quality: Built to meet OE specs for terminal alignment, dielectric strength, and conductive-path precision.
• Designed for OE Fit: Installs into the original distributor housing for reliable contact points.
• Heat-Resistant Materials: Made with high-dielectric compounds to withstand high voltage, thermal cycling, and engine vibration.
• Directs High-Voltage Spark: Routes ignition coil output to the correct cylinder for proper firing order.