On Wednesday afternoon, Donna and I rode the Spyder to our CPA, George Montgomery’s place to prepare our tax return. We spent about 45 minutes going through things to be sure it was all clear. George is a former full-time RVer and knows what the lifestyle is all about and what deductions we’re entitled to.

After we left, we stopped at Sprouts at Higley and Southern Avenue to pick up a few items. We were in the store for maybe 15 minutes and it was hot out. When we left, I stowed the groceries in the front trunk – called the frunk on Spyder forums and fired up the Spyder. It didn’t seem happy – in fact, it seemed like it was only firing on one cylinder.

I pulled out of the parking lot onto Higley Road and stopped at the traffic light. The Spyder was running rough. I shifted to neutral and revved the engine, but it didn’t change anything. When the light turned green, I accelerated but the Spyder wasn’t so responsive. It was only hitting on one cylinder and the acceleration was sluggish. With the throttle wide open, I was thinking we had a fuel problem. To be precise, I was thinking we had a vapor lock situation in one of the fuel injectors.

Fuel refineries change their formulations seasonally. Fuel intended for use in the winter is more volatile with a higher concentration of light end components. This makes the fuel easier to ignite on a cold morning and the light end components don’t vaporize and pollute the air in cold temperatures like they would in high ambient temperatures. Summer blend fuel is less volatile and doesn’t vaporize as easily thus reducing air pollution.

Here in Arizona we have unseasonably hot weather. Average temperatures at this time of year show highs in the mid-70s and lows around 50 degrees. We’ve had highs in the mid to upper 80s. I don’t think the fuel refineries anticipated the hot weather.

Back to the Spyder issue. The high ambient temperature combined with a 15-minute heat soak was causing an issue. Heat soak occurs when a hot engine is shut down for a short period of time. During this time, the underhood – or under tupperware in the case of the Spyder – increases. That’s right- the engine coolant temperature and surrounding air temperature actually rises after the engine is shut down.

When we were leaving Sprouts, the engine temperature was high. I think the fuel in one of the injectors was boiling – causing a vapor lock situation. The engine wasn’t making much power. When we left the stoplight on Higley at Southern, I gave full throttle to accelerate away with a misfiring engine. After a couple of seconds, as we cleared the intersection, the fuel flowed through the injectors and the Spyder had full power. It took off like a rocket! Luckily Donna had her right arm around my waist as she was lowering her helmet face shield with her left hand or she might have fallen off the back!

Today I plan to replace the front tires on the Spyder – they have plenty of tread, but I’ll explain why I’m replacing them in my next post.