98 Blazer Misfire

My 98 blazer with the 4.3L misfires bad when it is accelerating around 2k rpm and up (especially uphill). It happens mostly in first gear when it’s getting close to shifting. It misfires in cylinder 4 and 5(though it misfires much more in 4). Sometimes it drives so bad it won’t shift into overdrive. Replaced spark plugs, cap and wires and O2 sensors. The odd thing is once it warms up I will turn it off and when I turn it on it runs perfect. If it’s running bad it doesn't matter if it’s fully warmed up or not it runs bad but once I turn it off then turn it back on it runs good. .

When its running bad the engine will vibrate the car slightly (but definitely noticeable) at idle, but when running good the car doesn't shake/vibrate at all.

I've read many forums about people with misfire problems in their blazes but nothing about it running better after turning it off then back on.

Replacing the injectors next but would that have anything to do with running good after being turned off?

Any ideas what it could be?

Also engine is relatively new, only around 50k on it.

THANKS IN ADVANCE!!!

could be a fuel pressure issue. do you know what the code numbers are when its not running right?

No sorry I don't know the specific codes, just that it gives misfires in cylinder 4 and 5

if you don't have access to a code reader most auto parts stores will check them for free

A family member has a high end scanner and we have driven around with it while it was driving good and bad and there are no error codes that load up, it just shows misfires.

I had a 4.3 1998 Blazer that i was working on for a friend and i found that under the intake there are plastic lines going to the injector that was bad they call it spider line that come off a valve that feed fuel to all six injector hope that help.