CEL, P0411
#1
Moderator
Thread Starter
CEL, P0411
We all know this code, P0411, which everybody gets after installing an intake. Usually crossed vac lines or a backwards white check valve.
So while I'm doing a motor job, I decide to tackle the CEL which has been on for a long time. The guy even has "Check engine light" in his sig
BTW...I tried the flow of diagnostics in the Honda manual for 411 and the book is way off. Anybody who knows this stuff, read it carefully and you'll see why.
Anyway.....I hear the pump run when the car is cold, go over the lines and the check valve. All is good, except I don't like the way some of the lines fit as they were not the grey Honda lines that fit nice and tight. So I replace them, still get P0411 pending right away. Right away I suspect the Vaccum Control Valve, which is the little valve behind the Air Pump in the pic. (originally mounted to the airbox)
The valve clicks on and off, I can feel it. So I do my own tests, the valve opens and closes fine, and allows vac to pass at the right time. Still suspicious, I put the valve in my car and start it up, get P0411 pending right away in MY car. so I replace the valve thinking I've got it pegged, and realize this is not the only problem, but what cause the next as well.
The last think to check is the pump. It's sounds like it's spining pretty fast, with little resistance. I'm sure the ELD unit picked up on it and triggered the CEL.
Sure enough, I pull the bumper and find the pump housing had burned through, but the motor was ok and sounded fine. Enjoy :
So while I'm doing a motor job, I decide to tackle the CEL which has been on for a long time. The guy even has "Check engine light" in his sig
BTW...I tried the flow of diagnostics in the Honda manual for 411 and the book is way off. Anybody who knows this stuff, read it carefully and you'll see why.
Anyway.....I hear the pump run when the car is cold, go over the lines and the check valve. All is good, except I don't like the way some of the lines fit as they were not the grey Honda lines that fit nice and tight. So I replace them, still get P0411 pending right away. Right away I suspect the Vaccum Control Valve, which is the little valve behind the Air Pump in the pic. (originally mounted to the airbox)
The valve clicks on and off, I can feel it. So I do my own tests, the valve opens and closes fine, and allows vac to pass at the right time. Still suspicious, I put the valve in my car and start it up, get P0411 pending right away in MY car. so I replace the valve thinking I've got it pegged, and realize this is not the only problem, but what cause the next as well.
The last think to check is the pump. It's sounds like it's spining pretty fast, with little resistance. I'm sure the ELD unit picked up on it and triggered the CEL.
Sure enough, I pull the bumper and find the pump housing had burned through, but the motor was ok and sounded fine. Enjoy :
Trending Topics
#10
Registered User
Join Date: Mar 2006
Location: Elk Grove, CA
Posts: 566
Likes: 0
Received 0 Likes
on
0 Posts
interesting. well i had the code ever since i bough my car and guess what it does not even have the air pump system. so hopefully this weekend i can install my new air pump on and get rid of the annoy cel.