I have a 1994 Z29 5.7 L Auto....I have been having a rough hesitation that is not there if I rev in park (I know But I thought I could tell) in park it was fine and all gauges good...gooding down the road about 1500 rpm it starts to "Buck".. I drove it acrosss country 4 years ago and it was fine maybe once or twice...I fill up the tank and store it full ..winter gets down to 20 below sometimes but it is under cover and I never start it unless it is over 45 and I let it run 15 minutes too circulate...my x never to be named again kept it is his shop yard and tried dry gas....so I really need to tackle this..is it a bad fuel filture, a fuel pump going or injector...help

 

All I can offer is a bad coil... When mine went out (more than once) it was on the way to higher rpms and it would cause bucking. However I recommend you actually have someone diagnose the issue before dropping a bunch of money (although coils are not very expensive and quite easy to swap).

 

Let's move this to LT1 Based Engine Tech.

 

Does the car have old gas in it? That could be one cause. Can you check the fuel pressure? If the fuel filter has over25000 miles it should be replaced. Any check engine light?