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HELP!!! I have a 94 gmc safari sl mini van 4.3 v6 and it’s having acceleration problems from 0 to 40 it lags when i give it gas and this comes and goes. I tried checking the catalytic converter, fuel pump, fuel filter and still nothing same problem. I think its a computer problem or they did a diagnostic with a tech 1 already and it was saying catalytic (* spelling ) converter and fuel filter which have been checked professionally and its not the problem. They checked the fuel pump not the problem. All wires seem ok. I did have computer issues last year they changed the computer and that could be the problem but if anyone has any other suggestions. The distributor to spark plugs is not it or spark plugs. This is a throttle body engine and uses old computer that’s read only by tech 1 testers for diagnostic. Someone suggested i get a “Breakout Box” to do a deeper diagnostic but they don’t have those anymore. Not even in authorized gmc corporate affiliated mechanic/dealers have them. If anyone knows where i can get one online asap. Tomorrow i go to a mechanic who claims he can fix it and has 35 years of experience. We shall see. But any suggestions please help. One last thing it could be something to do with the throttle body positioning system or with the “Shaft” is what they told me or the throttle body itself or something that’s just one theory of many.