CMTOOL Exhaust Back Pressure Tester Kit with 6ft Hose & Carrying Case — 2.5" Dual-Unit Gauge

The CMTOOL Exhaust Back Pressure Tester Kit is a portable diagnostic set that measures exhaust-system back pressure with a high-definition gauge, 6-foot heat-resistant hose, adapters, clamps and a protective carrying case.

This complete kit gives mechanics and DIYers a reliable way to check for restrictive exhaust components—such as clogged catalytic converters, damaged flex pipes or obstructed mufflers—without removing parts. Everything nests in a custom-molded black carrying case so tools stay organized and protected on the road or in a shop. The kit’s features focus on ease of use, visibility and durability for repeat testing across a wide range of passenger vehicles.

How do I set up the CMTOOL tester and start a measurement?

Setup is straightforward: attach the correct adapter (M12 or M18) to the test port, connect the 6-foot nitrile rubber hose, and clip the gauge into place. Run the engine at the specified conditions—idle and at 2500 rpm—to compare readings against recommended limits.

• Select M12 or M18 adapter for the vehicle exhaust port.
• Connect the heat-resistant 6ft hose to keep the gauge outside the cab.
• Use clamps supplied to secure the hose during testing.
• Read pressure on the 2.5" gauge in PSI or bar; note color-coded ranges.

What readings indicate a restrictive exhaust and when should I be concerned?

The gauge provides dual units and a tri-color visual scale to help you interpret results at a glance. Typical guidance for this tool is less than 1.25 psi at idle and under 3 psi at 2500 rpm; values above those thresholds suggest restriction that may need inspection or component replacement.

• Idle: pressure should remain below 1.25 psi for most passenger cars.
• 2500 rpm: pressure should stay below 3 psi unless manufacturer specifies otherwise.
• Color zones on the dial indicate acceptable, marginal, or problem ranges.
• Repeat measurements after repairs to confirm improvement.

What makes the hose, gauge and case durable for shop use?

The kit uses a thickened nitrile rubber (NBR) hose rated to roughly 70°C for heat and wear resistance, suitable for reaching the exhaust port while staying outside the passenger compartment. The 2.5-inch gauge is fitted with a shock-absorbing rubber cover and calibrated pointer; the custom-molded carrying case keeps adapters, clamps and the gauge secure during transport and storage.

• 6ft NBR hose resists abrasion and temperatures up to ~70°C.
• 2.5" dual-unit gauge with protective rubber boot for impact resistance.
• Pre-calibrated pointer; adjustable to zero if impacted in transit.
• Custom molded case organizes components and prevents loss.

Can this kit be used across different cars and light trucks?

Yes—the included M12 and M18 threaded adapters cover many common exhaust test ports across passenger cars and light trucks. The flexible 6-foot hose allows the gauge to remain accessible while testing, and the clamps help secure fittings on a variety of pipe diameters and locations.

• M12 and M18 adapters fit widespread exhaust ports and threaded plugs.
• Clamps secure hose and adapters on varying pipe sizes during testing.
• Portable case makes it easy to carry between jobs or vehicles.
• Gauge reads in PSI and bar for universal interpretation.

Who is this for: The CMTOOL Exhaust Back Pressure Tester Kit is designed for professional technicians, automotive shops, mobile mechanics and serious DIYers who need a compact, repeatable way to diagnose exhaust restrictions. It’s best for users who want quick visual results, a durable hose and gauge, and a tidy carrying case to keep adapters and clamps organized for field or shop diagnostics.