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Hello friends,

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 antifreeze in the oil so I removed the intake and found a few problems:
1. The 'Spider' fuel pressure regulator (FPR) was leaking and washed in the interior of the intake clean in that area of the FPR.
2. All four corners of the intake water jacket were corroded and caused antifreeze to undermine the intake gasket and seep into the lifter valley and down into the oil pan.
3. 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 to clean it when rough idle symptoms started happening. I use the screened EGR gasket but continue having issues.

So, last summer removed the complete CPI intake. I thoroughly washed all carbon contamination from the upper & lower CPI intake with bottle washer brushes and gasoline & cleaners...
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 I continue to get 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 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?

Many thanks in advance for your responses.
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1 yes you can delete the egr valve but that doesnt necessarily mean you should.

2 to "fool" the computer you literally have to change the egr enable flag in the ecm's programming. you are not "fooling" the computer you are programming it out. i suggest searching on thirdgen.org in the prom burning section on the basics of how to do that. if you still want to go through with programming the ecm which you really should do if you delete the egr. bringing me to number3

3. this is the part where i explain why you may not want to delete the egr. the egr recirculates exhaust gases(hence the name) which is inert(to an extent) and helps cool the combustion chamber. this reduces the chance of pre-detonation/pinging allowing the engine to run more timing and leaner a/f ratios without blowing up, meaning better mileage and power from a small engine. if you were to not change anything in the programming and just delete the egr, you will get the check engine light and also could get pinging from the engine. with a higher octain fuel you could possible avoid pinging on the conservative stock engine tuning, but will still get the light. my guess is you want no check engine light, so you need to edit the programming anyways, so you might as well dig in to the rest of the tuning. here is where you make a choice. you can keep the egr and tune the engine with it and keep it clean(the tuning for this is easier and to some better as you can add more timing and less fuel). or, you can delete the egr, which will take 1running higher octain gas (might not be needed), or 2 (the "right" way) completely re doing the programming to richen the fuel curve without sacrificing the timing(tuning for this is harder and takes longer as the only way to get the most out of it is a lot of trial and error)
neither choice is wrong, and its not nearly as complex as it sounds in words and some of the negatives i have listed are worst case scenarios and may not be a problem for you. do be aware though i am not an expert on this, and have not done it myself on my blazer, i have just done the research for tuning the ecms in these trucks. i am personally in the process of learning and making the tools needed to reprogram the ecm. i may end up slightly wrong on some things but this is to the best of my ability what my research has led me to. i can help fill in some of the gaps between the thirdgen.org and our trucks when it comes to ecm tuning but you have to decide if you even want to bother deleting the egr and reprogramming the computer. if not your better off just cleaning it and checking it every 6 months or so.
also your coolant in the oil problem could also be coming from a blown head gasket or other problem as well so might ant to check that as well before dumping a lot of time and money just to have to re do it.