The injectors were more of an issue than the cam sensors. If you have good spark to that cylinder but it misfires I would go to the injectors
Reference the GM bulletin below
Bulletin No: 00-06-04-003
File In Section: 06 - Engine/Propulsion System
Date: January, 2000
Subject: Rough Idle After Start, and/or a Service Engine Soon (SES) Light
(Unstick and Clean Central Sequential Fuel Injection (CSFI) Poppet Valves)
Models:
1999-2000 Cadillac Escalade
1996-2000 Chevrolet and GMC C/K, S/T, MIL, G, P Models
1996-2000 Oldsmobile Bravada
with 4.3 L, 5.0 L, 5.7 L Engine (VINs W, X, M, R RPOs L35, LF6, L30, L31)
This bulletin is being revised to add new information to the Correction section. Please discard Corporate Bulletin Number 87-65-07A (Section 06 - Engine).
Condition
Some customers may comment on rough idle after start-up, especially if the vehicle has sat overnight. These symptoms may be intermittent. The Service Engine Soon (SES) light may also be illuminated. Current misfire, or history misfire codes may be detected with the Tech 2 scan tool.
Cause
A deposit build-up on the CSFI poppet valve ball and/or seat may cause the poppet ball to stick open or closed. In either case, the specific cylinder will be mis-fueled, resulting in a cylinder mis-fire condition.
Correction
A new injector unsticking and cleaning process has proven to be effective in restoring poppet valves to an "as new" condition. Injector replacement should NOT be considered as a correction for this customer concern.
The first step in this process is to make sure that the poppets are operational. The cleaning procedure will be ineffective on a poppet nozzle that is stuck closed. The J 41413 Evap Pressure/Purge Station, in conjunction with the J 44466-10 pressure regulator/ hose assembly, provide the required high pressure (150 psi) source to perform the unsticking procedure.
The J 39021 fuel injector tester and accessories provide the means to "energize" the injector. Some later model-year vehicles may utilize the Tech 2 to "energize" the injectors.
The second step of this process is to run the engine on a solution of 5% Top Engine Cleaner and 95% gasoline. This will effectively clean any deposits from the ball and seats of the poppets. It is very important that the engine fuel system is separated from the vehicle fuel system. Top Engine Cleaner may have detrimental effects on the fuel pump.
Parts Information
Part Number Description 12345382 Threadlock 1050002 Top Engine Cleaner (U.S.) 992872 Top Engine Cleaner (Canada) 12345104 Port Fuel Injector Cleaner (U.S.) 10953467 Port Fuel Injector Cleaner (Canada)
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use:
Labor Operation Description Labor Time J5645 Injector, Fuel Clean 1.3 hrs S/T J5645 Injector, Fuel Clean 1.0 hr G, M/L, P J5645 Injector, Fuel - Clean 01.1 hrs C/K
Diagram/instructions for replacement are attached below
Images (Click to make bigger)
Saturday, November 17th, 2018 AT 5:02 AM
