LT1-LT4 Modifications 1993-97 Gen II Small Block V8

First Start Rough Idle, Shaking

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Old Aug 27, 2012 | 01:10 PM
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Default First Start Rough Idle, Shaking

I just put in my recently rebuilt 95 lt1 into my 95 firebird formula

after priming the engine started it up for the first time, has great oil pressure, got to temp fine, no knocking. The issue is the car shakes and the engine is missing badly. The SES light is flashing on the cluster.

I borrowed a scanner and there are no codes present.

The car has new oem spark plugs and wires, and a "new" gm reman opti spark. The only mod to the car is pacesetter headers (they were on the car when I bought it)

This is my first lt1 and I was wondering where should I start diagnosing?

I did some searching and came up with a few ideas:

-Obvious thing that popped into my head is opti is bad?
-Coil?
-If I adjusted the rockers too tightly would this cause the issue? It was my first time adjusting rockers and am wondering if we got them too tight.

The method I used was spin the pushrod with my fingers tightening until I couldn't spin the pushrod very easily. Then tightened 3/4 turn. Would that be too tight?

The oil might smell slightly like gas as well


Any ideas would be great
Thanks
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Old Aug 27, 2012 | 01:22 PM
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From: Jackstandican
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Dead cylinder(s) is my guess. Unplug each fuel injector/ plug back in until you find the cylinder where the idle is not affected when injector is unplugged.
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