P0411 is a flow error, not electrical error.

 

Bill, the error code pops when the air pump kicks in for a second time.

Like this morning. Car was idling as I pulled it out of the garage. Air pump goes off. As I get back into the car and get ready to roll away, air pump kicks in again and the CEL with p0411 pops.

Is the code because there is a leak or because the air pump kicked in when it wasn't suppose to?

 

a few years ago my air pump would come on at odd times not just cold start. the dealer replaced it and i got it free, but i was just out of warranty, the labor was my nickle...that took care of the problem. it also ran on when the car was off!

 

CONTACTOR ASSY.
Part NO.: 39794-PCX-023
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I also went through a similar situation when I was wire tucking my S2K engine compartment. I broke one of the air nipples on the solenoid and did some research to get a new/used one. The one recommended for an S2K is (as above, retails for $143.00) I went to the local junk yard and found a similar one from an Accord that was mounted on the firewall to activate the rear motor mount (vacuum assisted). Cost $10.00 used, and has been working properly ever since. Also did the same replacement for a friend's S2K.

Don

 

Hey Max, I'd like to do this as well, since all my vacuum hoses have about 150,000mi and 9 yrs on them. What's the easiest way to figure out what needs to be replaced? Or, do you have a list or something?

 

I have never seen a s2k with code P0411 that needed a relay or any part at all. I have seen this code dozens of times. Trust me. Now CODE P0410 is a different story.

The pump is coming on as it is supposed to. The ELD is detecting a leak, because of the current draw variation of the air pump.

check your vac line routing, white check valve direction.

One other know issue is the air pump housing burns through on the back side, making a large leak.

 

It would be pretty silly to replace the air pump relay, as we all know it is obviously WORKING

 

Its common for an incorrect routing between the two vaccum lines that run by the intake manifold.

Also check the line behind the stock intake. It likes to come out sometimes. In the thread I provided below its in the first picture and it's the line where he labels Upper vaccum line. Where the white piece is the bottom line likes to come out. Hope this may help out.

https://www.s2ki.com/s2000/topic/609...-vacuum-lines/

 

Bill thank you.

I re-checked my work and a little line was not connected under the fuel rail. So thankfully, no inspecting the air pump required

 

All resolved here guys.

A small line under the fuel rail wasn't connected properly. On two passes it appeared proper but my third, and very pissed off pass this afternoon, I saw it from the right angle to fix