The PZERO Performance Intake is engineered specifically for the Mercedes‑AMG CLA45 to sharpen throttle response and unlock a more aggressive intake note. By reducing intake restriction and lowering inlet air temperatures, this cold‑air system helps the small turbo spool faster and maintain power through the mid‑range. This guide covers every step of the installation from prep to test drive, with tips gleaned from real workshop experience. If you want a crisper pedal feel and a soundtrack that matches the car’s personality, this upgrade belongs on your short list.

Tools and Materials

Before you touch a bolt, gather everything you’ll need. A clean, well‑lit work area and the correct tools prevent frustration halfway through the job.

  • Socket set – metric sockets from 8 mm to 13 mm plus a 10 mm deep‑well for tight spots.
  • Torque wrench – ¼‑ or ⅜‑drive, capable of 5–30 Nm (torque specs later in the guide).
  • Screwdrivers – flathead and Phillips, medium size.
  • PZERO Performance Intake Kit – verify the kit includes the filter, heat shield, silicone couplers, clamps, and all mounting hardware.
  • Shop towels – for cleaning the airbox area and wiping down hoses.
  • Safety glasses – debris can fall into the engine bay; protect your eyes.
  • Gloves – nitrile or mechanic’s gloves keep oil and grime off your hands.
  • Small vacuum or compressed air – to blow out loose dirt from the intake tract before disassembly.

Safety and Preparation

The CLA45’s engine bay is tight. Taking a few minutes to set up correctly pays off in smooth progress and prevents costly mistakes.

Work Area

Park on a level surface and let the engine cool completely – at least an hour after the last drive. A hot turbo and exhaust manifold can cause burns. Engage the parking brake and chock the rear wheels if you’re on an incline.

Disconnect the Battery

Use a 10 mm socket to loosen the negative terminal clamp. Tuck the cable away from the post so it cannot accidentally touch metal. Wait three minutes before proceeding – this allows the ECU capacitors to drain and prevents any chance of shorts near sensors or the MAF.

Remove the Engine Cover

The stock engine cover snaps onto four rubber mounts. Pull upward firmly at each corner, or use a trim tool to gently pry. Set the cover aside; you can reinstall it after the intake is in place, though many owners prefer to leave it off for better airflow over the turbo.

Removing the Stock Intake System

Factory intakes on the CLA45 are restrictive by design – quiet and emissions‑optimized. Removing them is straightforward but requires care around the MAF sensor and the turbo inlet.

Loosen the Hose Clamps

You’ll find three main clamps: one at the turbocharger compressor inlet (use a 8 mm or flathead depending on style), one at the airbox outlet, and one on the fresh‑air snorkel that attaches to the grille. Loosen each until the silicone hose can be rotated freely.

Disconnect the MAF Sensor

Unplug the electrical connector by pressing the tab and pulling straight off. Do not force it – spray a little electrical contact cleaner if it resists. Remove the Torx or cross‑head screws that secure the MAF housing to the stock airbox. Carefully lift the sensor out and set it on a clean towel. Keep the O‑ring seal; you’ll reuse it in the new intake.

Disconnect the Secondary Air Intake and Hoses

On the CLA45 there is often a secondary air pump hose attached to the lower airbox. Squeeze the quick‑connect fitting or unclip it. Also disconnect the crankcase ventilation hose that runs into the intake elbow. Plug the open ends with clean rags to prevent dirt ingress.

Remove the Stock Airbox and Snorkel

Lift the airbox up and out – it may have a locating pin at the bottom. Pull the snorkel from the front grille area by wiggling it free. Inspect the airbox for any leftover debris; blow it out or wipe it clean before discarding or storing.

Tip: Some stock airboxes have a foam cushion underneath that can tear. If it’s damaged, replace it with a small piece of closed‑cell foam to prevent rattles.

Installing the PZERO Performance Intake

With the engine bay cleared of the restrictive factory parts, you’re ready to install the PZERO system. Follow the supplied instructions, but these general steps cover the majority of kits.

Position the Heat Shield

Most PZERO kits include a carbon‑or metal‑reinforced heat shield that fits between the intake filter and the engine block. Install it first, using the factory mounting holes on the core support or strut tower. Tighten the bolts to 8 Nm – just snug, as overtightening can crack the heat shield.

Install the MAF Sensor into the New Housing

Transfer the O‑ring to the new MAF housing (if not pre‑installed). Apply a thin smear of silicone‑free vacuum grease to the O‑ring to ensure a good seal. Insert the sensor with the arrow pointing in the direction of airflow – toward the turbo. Secure it with the supplied screws. Do not overtighten; the MAF housing is often plastic and can crack.

Attach the Silicone Couplers and Clamps

Slide a worm‑gear clamp over each end of the main silicone coupler. Fit one end to the MAF housing and the other to the turbo inlet. Do not tighten yet – you need wiggle room to align everything. Install the second coupler, which goes from the filter‑side of the MAF housing to the fresh‑air snorkel or heat shield outlet.

Mount the Filter and Snorkel

Slide the high‑flow conical filter onto the MAF housing intake side. Secure it with the provided clamp. Route the snorkel or inlet hose to pull air from behind the grille or from the lower bumper area (depending on your kit’s design). Ensure the filter sits inside the heat shield and is not touching hot metal surfaces. A clearance of at least 12 mm is recommended.

Tighten All Clamps

With everything aligned, tighten each clamp to 4–5 Nm for small silicon couplers and 6 Nm for the larger filter clamp. Use a torque wrench; hand‑tight can lead to boost leaks. Recheck the hardware on the heat shield and MAF housing.

Reconnect the Crankcase Ventilation Hose

Most PZERO kits include a barbed fitting for the CCV hose. Push the hose fully onto the barb and secure with a small clamp. Verify the hose is not kinked or touching the hot turbo blanket.

Final Assembly and Checklist

Before you close the hood, go through this checklist to avoid common mistakes.

  • Engine cover – you can reinstall it if you wish, but many aftermarket intakes require leaving it off for proper clearance. Test fit it now. If it touches the new intake hoses, leave it off.
  • Battery terminal – reattach the negative terminal and tighten with the 10 mm socket. Torque to approximately 10 Nm.
  • Inspect all clamps – give each a final twist to confirm they are tight but not crushing the silicone.
  • Check for loose items – tools, rags, or plastic wrap inside the engine bay can cause serious damage. Remove everything.
  • Clean the area – use shop towels to wipe any oil or residue from the new intake and surrounding components.

First Start and Test Drive

Start the engine without touching the throttle. It may idle slightly high for the first 30 seconds as the ECU adapts to the increased airflow. Listen for whistles or hoses – any hissing under load indicates a leak.

Allow the engine to reach normal operating temperature. Take a short, gentle drive (3–5 minutes) staying below 3 000 RPM. Then perform three or four full‑throttle accelerations from 2 000 to 5 000 RPM to help the ECU learn the new volumetric efficiency. You should notice quicker pedal response and a deeper intake sound.

After the test drive, park and check for leaks once more. Use a shop towel to feel around each coupler while the engine is running – any air puff will be obvious. If you find a leak, tighten the clamp ¼ turn and recheck.

Performance Expectations and Maintenance

The PZERO intake doesn’t dramatically change peak horsepower numbers on a stock tune, but it does improve area‑under‑the‑curve. You’ll feel the most gain in the 2 500–4 500 RPM range where the turbo spools more freely. Throttle response becomes sharper, and the intake note adds a sporty edge without being obtrusive.

Filter Cleaning

The dry filter element should be cleaned every 10 000–12 000 miles using a recharge kit specific to the manufacturer. Never use oil on dry filters – it can contaminate the MAF sensor. Shake or gently vacuum the filter from the inside out. Replace the filter if it appears damaged.

ECU Adaptation

Some owners report a slight hesitation for the first 100 miles as the ECU fully adapts. This is normal. For faster learning, perform a full‑throttle pull from 2 500 to 6 000 RPM in third or fourth gear once the engine is warm.

Resources and Further Reading

Conclusion

Installing the PZERO Performance Intake on your CLA45 AMG is a weekend‑friendly job that rewards you with a more responsive throttle and a soundtrack that matches the car’s personality. With careful preparation, attention to clamp torque, and a proper ECU adaptation drive, you’ll enjoy a reliable system that stays cool in traffic and delivers when you need it. Pair this intake with a quality tune for even greater gains, but even as a standalone mod, it transforms the daily driving experience.