belief, but not trust

I believe in coincidences, but I don't trust them.

Here is the story

I wasn't happy with the performance of the Vega's carb when I first got the car. So I got a 'rebuilt' carb off fleabay and put the original on the shelf.

I finally decided to have it built, and swapped them out. Spent about thirty minutes tuning it in, and took a quick trip, about five miles round trip. It did ok, but seemed to surge a bit. But, next time I drove it, real trouble. It would only give power for about three seconds, then would not run above idle for at least ten seconds. Like the fuel wasn't feeding, and it was sucking the bowl dry.

So, a quick check on the fuel pressure showed a whopping one pound pressure. Also I noticed the fuel guage suddenly reading past full.

Obviously, the fuel pump and guage cannot be affected by the carb, but it is a pretty big coincidence.

I got a stock replacement for the fuel pump ( O'Reilly's had it in stock ) and popped it in the tank. Found a high resistance at the plug terminal for the sender unit. spun the terminal post, and the 400 ohm resistance dropped to zero. Cleaned the prong for the ground terminal.

Got the tank back in, fuel pressure checked @ 2.5 psi, guage working fine.

But now, the car won't run. Would start and idle for a few seconds, but not run.

Got tired of dinking with it, and put the old carb back on. It needed a few tweaks, undoubtedly because of the higher fuel pressure. Now it runs great.

I'm convinced the fuel guage issue was the high resistance at the terminal post, but the rest has me shaking my head.

Can't really decide if it was all an "everything at once" coincidence, or if swapping the carbs somehow triggered it.

Your story triggered my "Vega memory" when I first ran into the composite float in the carb, which over time absorbed fuel, got very heavy and much less buoyant, and finally didn't float much at all. Similar performance issues, and when I finally figured out that it was flooding out the bowl to the point of over flow on corners I bought a new float and was amazed two fold. First, the old float weighed about three times the weight of the new; and two, the car ran amazing because everything on it was checked, double checked and adjusted to spec by then from chasing the problem. Moral, don't trust that the solid composite float is OK. They're cheap, and they fail slowly over time.