my roomba i3+ evo's suction seems really weak all of a sudden, it's not picking anything up.

Diagnosis

The sudden drop in suction on the iRobot Roomba i3+ EVO is typically caused by a breach in the airtight seal of the vacuum path or a critical restriction in the airflow. When the i3+ detects a blockage or a clogged filter, the motor may continue to spin, but the static pressure required to lift debris from the carpet is lost. This most commonly occurs when the high-efficiency filter becomes saturated with fine dust (which blocks the microscopic pores) or when a "plug" of hair and cardboard forms in the throat of the bin. You can confirm this by performing a "suction test": remove the dust bin and place your hand over the intake port where the bin usually sits. If you feel strong suction at the port but the robot isn't picking up debris, the blockage is in the rollers. If there is little to no suction at the port, the issue is either a failing motor or a severe blockage in the internal vacuum channel. Additionally, check the Clean Base; if the bag is full, the robot cannot empty itself properly, leaving the internal bin overfilled and choking the airflow.

How to Fix It

Follow these precise steps to restore full suction power to your i3+ EVO:

1. Power down the robot by pressing and holding the CLEAN button for 10 seconds until the light ring disappears.
2. Press the release button on the dust bin and slide it out of the chassis. Open the bin door and empty the contents into a trash can.
3. Grasp the two ridged ends of the filter and pull it straight out. Do not pull by the fabric. Tap the filter firmly against the side of a trash can to knock out the fine dust. If the filter looks grey or black, it is saturated and must be replaced (Part # Roomba Filter for i3/j7).
4. Reinsert the filter, ensuring the ridged grips are facing outward and it is seated flush against the bin wall.
5. With the bin removed, look into the vacuum channel (the hole in the robot where the bin connects). Use a flashlight to check for clumps of hair or debris. Use a vacuum cleaner or a pair of tweezers to remove any obstructions from this throat.
6. Flip the robot over and remove the two multi-surface rubber brushes. Pull the hair-wrap guards off the ends of the rollers and clear any tangled hair or string. If the rollers are caked in grime, wipe them with a damp cloth and dry them completely.
7. Check the Clean Base. Open the lid and inspect the disposable bag. If the bag is heavy or the indicator shows it is full, replace it immediately. A full bag creates backpressure that prevents the robot from emptying its bin effectively.

If That Didn't Work

• Deep Clean the Sensors: Use a dry microfiber cloth to wipe the cliff sensors and the dirt-detect sensors on the bottom of the unit. If the sensors are coated in dust, the robot may not "realize" it is over a dirty area and will not engage the higher suction modes.
• Check for Air Leaks: Inspect the rubber gasket around the dust bin's entry point. If the gasket is pinched, torn, or missing, the robot will lose vacuum pressure. If you see a gap, the bin may need to be replaced to restore the airtight seal.
• Reset the Software: Perform a hard reboot by holding the CLEAN button for 20 seconds. This clears the temporary cache and forces the robot to recalibrate its motor speeds.
• Inspect the Exhaust Vent: Check the rear of the robot for any blockages in the exhaust vent. If air cannot escape the robot, it cannot pull air in from the floor.

Heads Up

• Filter Warning: Never wash the i3+ filters with water. The paper-based material will warp and lose its structural integrity, which permanently ruins the suction capability.
• Maintenance Cycle: Replace your filters every 2 months if you have pets or 3 months for standard homes to prevent motor strain.
• Bag Management: Do not wait for the "Bag Full" light to trigger; replace the Clean Base bag as soon as you notice the robot is leaving small piles of debris behind after a self-empty cycle.
• Brush Care: Remove the rubber rollers once a week to clear the ends. Hair buildup on the axles creates friction that slows down the brush speed, making the suction feel weaker than it actually is.