CMTOOL Exhaust Back Pressure Tester Kit — 2.5" Gauge, 6 ft High-Temp Hose, M12/M18 Adapters

The CMTOOL Exhaust Back Pressure Tester Kit is a professional diagnostic tool that measures exhaust system back pressure with a 2.5-inch gauge, M12/M18 adapters, and a 6-foot high-temperature hose for accurate, workshop-ready checks.

This kit gives technicians and home mechanics a straightforward way to check exhaust back pressure — a key indicator of restrictions, damaged catalytic converters, or other exhaust flow issues that can affect engine performance. Designed for ease of use, it pairs a clear, two-unit analog gauge with durable fittings and a long nitrile rubber hose so you can test from the driver’s seat or under the hood while the engine is running.

How does the gauge help diagnose exhaust restrictions?

The 2.5-inch high-definition gauge displays pressure in PSI and bar and uses three color bands to show acceptable and problematic ranges at a glance. You can compare idle and 2,500 rpm readings to determine whether the exhaust system is obstructed or operating normally.

• Clear dual-unit dial (PSI and bar) for quick reading.
• Three color-coded zones to indicate safe or excessive pressure.
• Recommended benchmarks: under 1.25 psi at idle, under 3 psi at 2,500 rpm.
• Gauge calibrated and adjustable if transport affects the pointer.

What fittings and hose features come with the kit?

The kit includes both M12 and M18 threaded adapters to fit common exhaust ports and a hose clamp for secure attachment. The flexible 6-foot hose is made from thickened NBR (nitrile rubber), giving it abrasion resistance and stability at elevated temperatures up to around 70°C.

• M12 and M18 adapters for wide vehicle compatibility.
• 6-foot hose length to reach comfortably from driver position or workbench.
• High-temperature, wear-resistant NBR construction for longevity.
• Included hose clamp secures the adapter during live testing.

How durable and portable is this tester for shop or field use?

The gauge head is protected by a rubber vibration cover that cushions impacts and improves grip, while the compact kit fits neatly into its carton for transport. Components are checked and calibrated before shipping to minimize setup time and ensure reliable readings right away.

• Shockproof rubber cover reduces risk of damage from drops or vibration.
• Compact carton packaging for organized storage and easy transport.
• Pre-checked calibration with user-adjustable zero pointer if needed.
• Robust materials intended for repeated shop use and DIY repairs.

How do I use the tester safely and get accurate readings?

Attach the correct adapter to the exhaust access point, clamp the hose securely, and run the engine at the specified idle and 2,500 rpm tests while monitoring the gauge. Allow the engine to warm to operating temperature and follow vehicle manufacturer precautions for live engine work.

• Select M12 or M18 adapter that matches the exhaust port thread.
• Secure hose clamp to prevent leaks during testing.
• Warm the engine before testing and note readings at idle and 2,500 rpm.
• If pointer isn’t at zero, remove cover and realign the pointer; calibration remains intact.

Who is this for: The CMTOOL Exhaust Back Pressure Tester Kit is built for professional mechanics, independent technicians, and knowledgeable DIYers who need a reliable, portable instrument to evaluate exhaust flow and diagnose restriction-related issues. It’s suited for automotive shops, mobile service professionals, and home garages working on a wide range of petrol and diesel vehicles where M12/M18 fittings and back-pressure measurement are relevant.