I’ve had my car, a Mazda MX-5, for almost six years now. In that time, I’ve raced it in autocrosses, driven it in rallies, and destroyed the engine in a flooded street. Since that flooding event, I’ve given up on the hard-driving autocrosses, but it hasn’t slowed down much at all. I still put about 30k miles a year on it. The body and transmission have 174k miles. The engine, a little less at 100k.
Lately, it seems like I’ve been having to work harder at keeping the system running well. I was having a problem with cold starts on cooler mornings. This was cleared up by cleaning the IAC valve – the Idle Air Control valve. It’s a simple procedure involving unscrewing something and dousing it with cleaning fluid. You should do it each time you change the air filter, but I seemed to have to do it more frequently than that.
Then I started having problems with the engine bogging down when I decelerate to a stop. This was solved by cleaning the throttle body. That’s a slightly more involved procedure involving unbolting a part and dousing it with cleaning fluid, then wiping off the carbon buildup. I had to do it twice because I wasn’t thorough enough the first time.
Lately, things just didn’t feel quite right. I knew I needed some critical safety maintenance, like brakes and tires, so I got both of those taken care of. That made the ride much more smooth and quiet, but something was still off. The engine seemed like it was struggling and the shifting was rough. So I planned on doing some internal cleaning.
I stopped at AutoZone and picked up some Seafoam. I’ve used Seafoam on my cars for a while and each time I do, I am surprised by the results. There is a great argument as to whether it really does anything at all or whether it’s all in your head, but I am a believer.
I added a full can to my half-tank of gas yesterday when I got home. When I started the car up and drove it this morning, it was immediately noticeable that something was better. The engine was smoother, the acceleration was better, the shifts weren’t clunky anymore.
The weirdest thing was the accelerator. My car is drive-by-wire, so there’s no cable literally pulling on the throttle body. Yet somehow, the pedal was more responsive. I didn’t have the previous sensation of one position having too little power and with a slight pressure change, suddenly having too much power. That was causing me to surge in my driving, and I would spend a lot of time speeding up and slowing down. Now, I could hold a position exactly where I wanted.
When I noticed that the car was running smoother, I reset my MPG sensor. From almost six years of ownership, I know that my highway drive to work after resetting the computer would show about 34 MPG, and then it would drop as my city driving would factor in. Getting to work today, the MPG read 36.8. That has to account for something, right?
But I’m still not done. I’ll also be adding Seafoam to the intake line this weekend. Then I should be caught up on that level of maintenance. Cheap and easy fixes are the best.