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Hello, kind folks of CZC, long time lurker here! Normally I can figure out my issues through the vast information already here but this is the first problem I came across that I feel the need to post and get some more direct answers. The car cold starts every single time and runs from anywhere to 30 seconds to 2 minutes. The RPMs bounce from around 750 to 1,000 until it puts up a fight to stay alive and then stalls out. Very occasionally white vapors will pour out the carbs trying to crank her right back up. After that I will have to wait about 5 minutes for it to crank back up. Now the problem first arose with some bucking on the highway, normally around in the 2,000 to 3,000 RPM range. Then it slowly came to the state that it is in now. Little bit about the car. 1974 260z. Stock 2.6L with Ztherapy carbs. Electric fuel pump. 77,xxx miles. Daily Driver. Owned about a year. I started the search for engine harmony in the ignition. Pulled plug wires until I came across #1 to see the tip of the plug and plug wire was rusted completely. I then replaced with NGK plugs and wires along with cap and rotor thinking that had to be the problem. Same symptoms afterwards. I then started to believe I became victim of the timing chain jump myth but after checking TDC with marks on the rotor, cam, and piston everything seemed to be in line. Timing set to 8 degrees at 750 RPM's the few times I had it running well enough to do so. Valves were adjusted tight a couple months ago. Moved on to a dry compression test and the results seemed consistent enough to rule out any issues there. 1. 160 2. 160 3. 165 4. 175 5. 170 6. 170 I then moved over to carbs and disassembled the majority of the body and cleaned out what I could do the best of my ability. I came across a crack in the top portion of one of the floats. Would that possibly cause flooding issues after a certain period of time of running and cause the white vapors from the carbs? I redone the fuel tank and cleaned out the lines when I first bought the car so I believe all is good there. Clear fuel filter installed so I do see clean amounts of fuel flow going through it. Been running the same fuel delivery setup for months. Brake master vac always had a leak in it but spraying carb cleaner around other lines had no effect on RPMs. I grew a terrible stubble of facial hair to profusely scratch while trying to think of a solution to no avail. I feel like the problem is so minuscule and I may feel like a dummy afterwards but better a dummy that has a running car than none. I'm losing days at work, patience, and money at parts to trying to get it going again. Sorry for all the reading material. Any input appreciated guys!