I am trying to get my 88 t2 to pass emissions. The air pump and secondary air injection system are working and I changed my spark plugs and air filter. I just replaced my main cat and noticed that there is no air tube running to the cat at all. I am positive that this tube must run from the air pump somehow, but do know where it runs from. Can anyone let me know where this tube originates? Also, can I possibly pass emissions without the tube, as I hear the air pump only helps the cat at low rpms? Any help is greatly appreciated.

 

Based on my knowledge of 1st gen systems, I would guess that you will pass emissions but your cat will soon burn up without that air tube being hooked up.

But wait for a 2nd gen expert to speak to this before making any decisions. Good luck...



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95% of air pump air is fed to the exhaust ports, while only a tiny bit ever goes down the split air pipe to the cat. I'd bet that you could pass a sniffer test with the pipe missing, but not the visual. The pipe normally hooks up to an opening on the lower intake manifold, next to the turbo coolant feed line.