Forum Discussion

BFL13's avatar
BFL13
Explorer II
Dec 27, 2017

Air Pipes to Catalytic Converter Question-Photo added

Update--question reposted here on 1 Jan-- For the 1991 E350 rig in the sig. Question is which of the two air intakes to the catalytic converter comes from which two pipes up by the engine? At...
DiskDoctr's avatar
DiskDoctr
Explorer
Dec 27, 2017
Here is a thread explaining some things about the air pump Thermactor system: https://www.ford-trucks.com/forums/1076650-air-injection-and-smog-pump-delete.html

Sorry I don't have the answer you are looking for. But I am still searching.

From my pics, it seems that if the lines don't cross, the one at the middle of the catalytic converter (not the front) is closest to the engine.

Does it matter which line is which? I don't know or why?

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