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SoGT Folks: 1994 Blazer 4.3 "W" CPI "EGR" Removal/(DELETE?) Question

Hello friends,

Well, this question may be for the Sonoma GT (SoGT) folks (since their CPI 4.3 is same as my engine configuration), moreso than you SyTy folks but I appreciate anyone chiming-in with their thoughts/suggestions.

I own a 1st Gen 1994 S-10 Blazer two-wheel-drive, 4.3L "W" with CPI 'Spider', 4L60 auto, and air conditioning.
I purchased this Blazer from the original owner in Glendale Arizona in 2007.
It currently has 150,000 miles but has had no major repairs; it was well cared for and is in excellent overall condition.

Last summer I found a small amount of antifreeze in the oil when I did an oil change so I removed the intake and found a few problems:
1. The 'Spider' fuel pressure regulator (FPR) was leaking and washed a bit of the interior of the intake clean in that area of the FPR.
2. On all four corners of the intake, the water jackets at the intake mounting surface were corroded/pitted and caused antifreeze to undermine the intake gasket and seep into the lifter valley and down into the oil pan.
3. Both Cylinder Heads EGR Ports were closed off (Carbon clogged) and considerable carbon was built up throughout the CPI intake & EGR Valve

I've removed the EGR valve a few times during the summers of 2007/08 to clean it when rough idle symptoms started happening. I use the screened EGR gasket but continue having issues.

So, last summer I removed the complete CPI intake. I thoroughly washed all carbon contamination from the upper & lower CPI intake with bottle washer brushes and gasoline & cleaners; NOT necessary I know...
I repaired the lower intake water jacket port mating surfaces with JB Weld as per suggestion from the local engine rebuild shop who stated they have done that similar repair frequently verses welding the pitted area and machining the intake mating surfaces smooth.

Well, after reassembling everything including installation of a new CPI 'Spider' assembly and fully cleaned EGR Valve, and FELPRO gaskets, fresh antifreeze & oil change, I continue to get ever-so-little antifreeze seeping into the motor oil so I suspect the JB Weld hasn't worked.

This winter I searched the internet and found a brand new, CPI intake assembly that was removed from a GM assembly line "take-off" engine that was used for dry run testing. The fellow I purchased it from sent me everything complete including all sensors. When I separated the upper & lower intake plenum, everything was shiny clean aluminum having never been heat soaked or subjected to a fire-up.

I am now getting ready to break down my engine again, including removing the heads to replace head gaskets, to swap in the new CPI intake.

1. My question for you folks is whether I can "DELETE" the EGR Valve on this particular "CPI" engine?
2. IF so, what is the process required to fool the computer that the EGR has been disabled?
3. Will the EGR removal cause issues with engine timing, fuel/air mixture issues or any other challenges?

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