Do fuel injector cleaners actually work?

Verified-purchase reviewers consistently report smoother idle, reduced hesitation, and modest drivability gains on higher-mileage or neglected engines, particularly with PEA-based concentrates like Chevron Techron and Red Line SI-1. Results are usually most noticeable on vehicles with existing deposits; a clean, well-maintained engine may see little change. Note that our data here is dominated by retailer reviews rather than independent lab testing.