Code 63 issues

[Alibi]

Hi all. This is in the '88 LeSabre. I've been fighting a code 63 ever since I've had the car. IIRC, 63 is improper ERG flow. I have swapped EGR's with one out of a wrecked car and still get the code. I can swap in another EGR off my '89 if need be but I'm suspecting other issues.

I believe newer versions had issues with the EGR pipe cracking, is that a possibility on my Vin C? If so, do I just get it welded up or can I JB weld it? Or just outright replace it?

Anyone have any experience troubleshooting this? I have a FSM so I'll refer to that next but hands-on experience from someone here is always good too.

[Alibi]

I'm still not making much progress on this. My FSM is telling me to either replace the EGR (which I've already done with a junkyard unit but can do with yet another one) or check the ECM.

So.... looks like I'm going to swap in one of my spare ECM's and the EGR off the '89 and see what happens.

Any other suggestions?