high rpm surge

[TSL]

Any suggestions for a high rpm surge? Surging bad
72- (350SLC) 116 engine fuel injection. Above 4500 it starts. And then sometimes it doesnt do it, comes and goes. Part throddle, idle and just cruising is just fine and coming into it slowly is just fine.
4speed auto - super low first gear revs all the way, first gear above 5000 it starts a little, 2nd gear fine up to 4500 and same with 3rd.
Gas mileage is good.
New dist cap and rotor
New wires
Replaced points for Pertronix
Plugs good
Air filter clean
The faster you go at full throddle the more it becomes, performance is great until you put petal to the metal
Important car show coming up and need her to be running her best.
Thanks,
Tim

[bdemir]

try replacing the o2 sensor and the idle control speed vavle. I did mine and it is fine i think. Took it to the dealer and they said that this should cure the problem. Lets see i will post again if it comes back.


Bedros

[TSL]

Bedros,
Thanks for the suggestions, I discovered what had happened. It was the spark plugs. Took them out and they were all a bright red. I guess it came from the fuel injector cleaner I had put in, or the water injection I had put on, don't know which. Less than 7500 miles on them, popped old ones back in just for a quickie test and runs great. Just a guess but that did it.
Again thanks.
Tim