Slow Car Fast
June 23, 2011 - Ah, nuts.
I spent a couple of hours running around some local roads shooting a bit of video and generally having fun with the car. The exhaust noises started coming back as the car got hot, but otherwise it behaved itself. Even with an ambient temperature around 95F or so, it didn't have any overheating problems. It did act a little cantankerous on a couple of hot starts, but cycling the key solved that. Quick car, let me tell you. The video will be along soon.

But unfortunately, the fuel problem returned. After running happily for all the video, I was heading home when the car started to stumble and then died in front of a gas station. I pushed the car into the lot where it was safe, and started poking around. My electrical connection seemed fine, but again the pump sounded a bit labored when it ran. I could sometimes get the car to fire up, but it would only fire a cylinder sporadically, just enough to keep it turning over but not much else. So I left the car and occupied myself elsewhere for half an hour.
When I got back, it fired up happily. I made it almost all the way home before it stumbled to a halt again. I parked it by the side of the road and again, a half hour later, it fired up.
So whatever is wrong is probably related to heat. I'm thinking it might be the pump itself. The pump I'm using is one that was sitting around my garage, and probably last saw action a decade ago. Foolish, maybe. But it's been working happily so far. The pump is fairly well protected from heat, although there is one of the exhaust pipes about a foot away. It doesn't feel hot to the touch, nor do any of the fuel lines.
It's possible that the input screen on the pump is clogged. Because the filter is also the regulator, the pump is pre-filter. It's quite likely there was a bit of debris in the tank despite my best efforts. I'm not sure that would manifest itself quite like this, but I'll investigate it none the less. I'll probably just swap in a new pump of the same type to be sure.
tags: debugging