I'm a Honda enthusiast for many years including my L15a1 swapped Insight project however this is about my lowly 2008 Honda Fit Sport A/T with 140K miles, my current daily driver. I originally bought this car for my wife but since I'm the one that commutes 50 miles per day (and has the lead foot) I have been driving the Fit as my daily. I never really liked it as it was just a little too slow for my tastes but a car is a car..... Last winter though the car would run really rough when cold, gas fumes were present and if I didn't let it warm up it would stall which is a huge PITA with an automatic. So many things online about this I started with plugs and having a spare engine I also swapped to a known good set of coils and no change. Now if the valves were this bad I would think that there would be burnt valves or mechanical damage and when I got in there the valve were pretty close to spec... So I pulled the injectors and took them to a buddy's race shop, he has an injector matching service and while I didn't have them matched only one of them had a normal spray pattern and one passed almost no fuel until it was opened up all the way with full pressure. After the ultrasonic bath all four looked like new......

NOW THE CAR DRIVE BETTER THAN IT EVER DID!!!

Not only is the throttle response 10Xs better and it's a bit quicker but my Ultragauge confirmed average MPG has gone up from 29 to 34 in 3 months time and I'm driving faster!!

I'm not saying that additive don't work and not to try, also pulling the injectors out is not the easiest thing to do on the L15 but it's definitely worth it especially when doing the valves since you're already halfway there. If you don't have access to this service you can buy refurbished OEM injectors for under $100 on ebay and is TOTALLY worth it.

My PSA for the day!