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I'm getting this P0410 code. Cleared it, and it's returned (with a C). Have no other P codes currently. No P1415/1416, no P0412/0418 codes.
I've searched a bunch and seen a bunch of info. Based on that info:
1) I tried swapping the smog pump relay and horn relay, and well, the horn worked before and still works, so it seems the relays are good.
2) I disconnected the rubber hose (thanks Bill Curlee for the great pic) on a cold start, and I get air blowing out of the left/fore hose stub, and vacuum into the right/aft stub (not sure how much vacc there should be but there's enough to feel it with my finger). This seems to indicate that the smog pump is functional, that there is no problem with the vacuum line to the pump and the control valve, that the hoses between air filter and driver side check valve are OK, and that the drivers side check valve is functioning.
Are my assumptions above correct? What should be my next step(s)--what to check/swap next? Is there an easy way to check the rear/passenger check valve?
When I purchased my 2001 it had the P0410 code. I looked into moving the check valve from behind the manifold to the passenger side of the car. I then just bit the bullet and removed the manifold and replaced the valve. It was not that difficult of a job and just better to do it and get it over with. The original valve had 144,000 mile on it so I do not think I will have to do this job again while I have the car. I am 67 years old and still able to do my own work, but there are garages out there that would do this job for reasonable amount. Good luck with your repair. It is also possible to have someone just tune out the code.
Thanks. I'm almost 100% certain I can remove the manifold, but my question is more whether I'm on the right track.
When you had the P0410 code, did you have any other codes? How did you know it was the passenger side check valve that needed to be replaced? Did you also replace the drivers side?
Thanks. I'm almost 100% certain I can remove the manifold, but my question is more whether I'm on the right track.
When you had the P0410 code, did you have any other codes? How did you know it was the passenger side check valve that needed to be replaced? Did you also replace the drivers side?
When I purchased the car the PO told me that the P0410 code was tuned out due to the passenger side check valve leaking. I had the PCM reflashed for the fuel gauge problem and I had the code again. I then checked the pump output by taking the hose off and feeling the air flow which seemed fine. I tried spraying WD-40 into the line going to the passenger side check valve and it did not solve the problem. I then pulled the intake manifold and replaced the passenger side check valve and the code went away. Later I replaced the driver side just because it had the same amount of miles as the rear one. When I removed the valve I had to take the valve and tube off the car to get it changed. Here is a picture of the valve location
Most often it's the check valves that cause these codes---They carbon up and won't close- and leak---They are pesky---and hard to diagnose---
On my 98 I finally gave up and installed air tube block off plates on each side of the exhaust manifold---They look like thick gaskets so a smog shop won't know they are blocked----You will have to turn the air pump OFF in your tune as well as to unplug the air pump pigtail-------THEN you must all set all the secondary air codes in your tune to read "not reported" and "no mill"----This will eliminate this problem forever--
As far as smog goes---No affect on the sniffer-- and the readiness tests for the air pump system will read "ready"permanently
So, from what I can tell, the rear check valve is threaded directly onto the hard line that is bolted to the passenger side exhaust manifold, and connects to a rubber hose that is connected to another hard line on the drivers side. That hard line in turn connects to another rubber hose on the drivers side.
Is the rear check valve hard line bracketed to the engine at all? Zachaeous, your 2nd pic shows a bolt head and bracket, basically right in the center. Does that hold the hard line down, or is it for something else?
So, from what I can tell, the rear check valve is threaded directly onto the hard line that is bolted to the passenger side exhaust manifold, and connects to a rubber hose that is connected to another hard line on the drivers side. That hard line in turn connects to another rubber hose on the drivers side.
Is the rear check valve hard line bracketed to the engine at all? Zachaeous, your 2nd pic shows a bolt head and bracket, basically right in the center. Does that hold the hard line down, or is it for something else?
Yes that is exactly right. The bolt holds the hard line to the engine cyl head. The bracket is slotted so you can loosen the bolt and after taking the rubber line and the two bolts off the right side exhaust manifold out you can lift the whole assy. up and out. That bolt on the back of the head is a little hard to get at but it can be done. I think I used a 1/4" drive ratchet with a flex head to get to mine in the car. The reason I had to take the whole line out to change the valve I could not get the wrenches I had in the area to unscrew the valve from the tube while it was bolted in, no room to work.
2 yrs ago I had the rear giving the code,,, disconnected them (both sides) and from the Y..
Sprayed brake cleaner in the lines (lots of it) and used my air hose to blow back and forth till it was clean.. keep blowing it out with air in both directions until it's dry...
After that I put a fair amount of W-D40 in the lines, and connected it all back...
Started it up and all was good...Still working after 2 years,,,NO more codes.
Hope this helps,, and less work too.
mike v
When I purchased the car the PO told me that the P0410 code was tuned out due to the passenger side check valve leaking. I had the PCM reflashed for the fuel gauge problem and I had the code again. I then checked the pump output by taking the hose off and feeling the air flow which seemed fine. I tried spraying WD-40 into the line going to the passenger side check valve and it did not solve the problem. I then pulled the intake manifold and replaced the passenger side check valve and the code went away. Later I replaced the driver side just because it had the same amount of miles as the rear one. When I removed the valve I had to take the valve and tube off the car to get it changed. Here is a picture of the valve location
So, once I get that bolt out will I be able to remove all my air pump lines completely? Can I get it out without removing the manifold? I have no air pump, I've already removed part of the system, had it tuned out, and my car still passes NJ inspection. It sure makes it easier seeing and getting to the spark plugs.
It sure seems that way. You'll need some kind of blockoff plates for the manifolds, unless you just crimp the hard lines to a stub and weld the crimp shut.
OK, so I got around to this. I decided to replace both valves. I was unable to get the valves off with the tubes attached to the car. The drivers side tube was easy to get off--2 bolts w/ 10mm heads, a hose clamp. For the passenger side I had to break the intake loose to get at the rear. Loosened the bolt at the back (seen in the photos above) with a 13mm socket and a flex ratchet, and the 2 bolts at the manifold. Breaking the valves free of the tubes was yet another ordeal. I ended up using a 1" deep well socket on the drivers side valve, with a 22mm open end wrench on the tube hex. Even then, I needed to use a torch to heat up the threaded section of the valve to get it loose. Same with the passenger side, except with the socket the valve just spun (guess the stamped edge/seal had loosened up, so I had to use a crescent wrench and hammer on the hex of the valve, plus heating up the threads on the valve.
I had this problem too with the P0410. It turns out my smog pump was intermittent, and I traced it down to the actual harness pack at the top of the pump (e.g. impossible to get to). And as murphy's law would have it, any time I had the car parked and I tried to diagnose it, it would work. Eventually, I jumpered the power terminals in the fuse box to bypass the relay then crawled around, finding the intermittent condition. Cleaned and bent the weather pack pins then dielectric greased the crap out of the gasket.
It was probably from old age- car is a 98 and 205k miles, daily driven even in the snow/salt. Not sure if this is your problem, but based on what you've said so far, it's worth checking out.
I remember that you checked the pump output before you changed the valves. If in fact it is not a intermittent problem with the pump not running I would get someone with a scanner that can watch what your front 02 sensors are doing in real time. They can log what voltage changes are taking place when the car is first started. Good luck with your repair.
I had this problem too with the P0410. It turns out my smog pump was intermittent, and I traced it down to the actual harness pack at the top of the pump (e.g. impossible to get to). And as murphy's law would have it, any time I had the car parked and I tried to diagnose it, it would work. Eventually, I jumpered the power terminals in the fuse box to bypass the relay then crawled around, finding the intermittent condition. Cleaned and bent the weather pack pins then dielectric greased the crap out of the gasket.
It was probably from old age- car is a 98 and 205k miles, daily driven even in the snow/salt. Not sure if this is your problem, but based on what you've said so far, it's worth checking out.
OK, so how do you get at the harness pack at the top of the pump?
Latest: I decided to check things out at the pump. Removed the 7mm head SEMS screws for the plastic panel covering the pump. Pulled off the rubber vacuum elbow. Stuck a boost gauge on the end while starting the car and got no needle movement. Should have just tried to blow on it first, because when I did that I discovered I was able to blow (and suck) air, with the motor off. I was able to hear air coming from somewhere towards the passenger side. No way to determine exactly where while blowing. Undid some more screws on passenger side, reaching into fender for vac tube ends. I'm assuming the plastic vac tube cracked at some point along the run between the secondary AIR solenoid and the valve at the AIR pump. I've read about folks with similar experiences having their battery leak acid which perforates the tube, but I saw no evidence of acid--probably the plastic tube just cracked from heat or age or physical stress.
Ended up breaking off the nipple on the vacuum reservoir and had to take off the fender to get access. Used Amazon Prime to get a new solenoid (also inside the fender, above the reservoir) just because I didn't want to have to go back in a second time. The plastic vac tube is largely wrapped up in the harness spiral wrap, so there's no easy way to replace it in kind. So I just left the tube in place and ran a rubber hose from the solenoid to the AIR pump valve, routing it along the OEM location with the harness and tying it to the spiral-wrap with a few zip ties. I also replaced the piece of hose from the solenoid to the vac tees with rubber.
Previously the P0410 code would come back in a day or two, and so far it's been 3 days and it hasn't come back (knock on wood), so I'm hopeful that this problem has been solved. As to why I was able to get airflow out of the pump, I don't know. Maybe the crack in the tube was small enough to let the valve operate, but big enough to pop a code. Hopefully this thread helps someone else out in the future. Check the vacuum hose even if you're getting air out of the smog pump!
P0410 code
