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Discussion Starter · #1 ·
Hi All,
First time post here but I have been searching the forums (here and elsewhere) but haven't found the info I'm looking for. Just for grins we removed a blown 2.5 w/722.4 from my 1990 124 and dropped in a 3.0 w/722.3 from an 87 124 that I'm parting out. Install went smooth and most vacuum lines and electrical connections were identical except for a couple and thats where I need help. Starting with the vacuum I have decided to eliminate the EGR. The wastegate on the 3.0 is not vacuum controlled so no biggy there but there is an air recirculation valve physically located between the EGR and wastegate valves - what is it's purpose and does it need to function? It doesn't even show up in the EPC but I did find it in a vacuum schematic for Federal Emission vehicles. Also, any ideas as to which of the 3 vacuum switch circuits I might could use to control it if needed? Maybe the circuit used to control the air flap on the 2.5?
I am having to use the air meter from the 87 due to fitment of the hose between it and the turbo. Everything else seems pretty much the same (IP, C/C, etc).
Thanks in advance,
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