Fantastic explanation of Secondary Air Injection system

[Masta Shake]

I think I have a bad combi valve but I may have missed something. Have had terrible fuel economy lately. When the van starts and is cold it sputters at the exhaust which has been blamed on the combi. Before I just replaced it I wanted to see how it works and found this video. Now I have a few other things to check first.


Link

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As a good friend told me when I got the Syncro: "Welcome to the an intense love/hate relationship".

[mkscott2]

Uncanny timing. When evaluating for ease of access to the oil pressure switch, I noticed that two of the mounts on this pump were completely sheared off. Ordered replacements from GAP. Not sure how common a problem, but for other's reference, they are part # 06A133567A.

[Abscate]

I want to hire this guy for all auto videos - great explanations, keeping concise, good tidbits on how to repair things. Well done.

I tell people the whine when I start up is my aftermarket APU/Supercharger
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.ssS!

[AlexandMary]

My question is how do we simulate the circuit to satisfy the ECU?

or what makes the ECU throw a code if the pump doesn't work?

[mikemtnbike]

First check to make sure your relay works. You can do this with VCDS on a 1995, if you’ve got that.

Then there seem to be two answers to this cat skinning. One is to replace with a later model pump etc that is not NLA like our 1995s. I’ve read about this on VWvortex. You have to modify the wiring harness. You might be able to us a SAI system from another car, same era,same digifant- like a Jetta or cabriolet. Not sure about that.

The other answer is to trick the ECU with a resistor. Again, VWvortex has info on this albeit on different models.

This is all on my to do list but not until winter, I just want my check engine light to not be on all the time so I don’t have to keep checking for new codes.
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1991 Vanagon GL 2.1 AT Westfauxlia. "Frankie" Totaled https://www.thesamba.com/vw/forum/viewtopic.php?t=764510&highlight=carnage
1995 Eurovan Camper "Marzivan"
2020 GTI SE manual

[Abscate]

It probably looks for a voltage drop on the OXS to sense the extra air, in which case you want a diode, not a resistor
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.ssS!