[propuckstopper]

Greetings everyone. I hope all is well. Just last night, my 1965 GTO Tri-Power car began bucking or surging. The idle is good, but from about 1000-1600 RPM it goes down the road and kind of acts up. It is not terribly bad, but it is bad enough that I noticed it, as did my wife from the passenger seat.

A little history: stock engine completely rebuilt five years ago (low miles still), carburetors rebuilt at the same time by me with proper parts and DAG sealant, and distributor completely rebuilt as well. Up until last night, the car was as smooth as a brand new car regardless of RPM. I never run ethanol fuel.

The only thing that has been touched since my last drive (one month ago) were the slotted airhorn screws and washers. When I rebuilt the carbs five years ago, I re-used the old screws and washers as the vendor was out of stock on them. I finally got around to ordering new ones, and I installed them. Now, I did remove the front carb airhorn to take a look inside the carburetor for dirt (none), but did not touch anything else on any other carburetor, save for changing the airhorn screws slowly and one by one.

So, does anybody care to take a stab at what this new issue may be? It seems like it could be lean in that RPM range, but why all of a sudden? I can't see anything having changed with the carburetors, but I did "touch" them recently so naturally this is what I am suspecting.

Again, idle is good and wide open throttle is good. It is just cranky from about 1000-1600 RPM. Thanks!