P0410 OBDII code

What model and year car?

Mike

It just means your air pump system is not working. This will not affect anything in the way the car drives, the only effect will be an increase in cold start emissions. (And the check engine light as well.) Probably what's happened is the SAS (SAS = secondary air system) valve has failed in the slightly open position, allowing exhaust to flow into the air pump, which is helpfully located at the lowest possible point so condensation fills it and eventually works its way into the motor, ruining it. However there's a control system, partially vacuum, partially electric, which can fail as well.

The details on your car are slightly different than the 850, the relay is in the "Main Fuses" box, but look at:

er..Mike..What kind of car is it??

It's a 1998 S70 T5.

Those Bay13 pictures are great. Is there any possibility that battery acid might have eaten through anything, and thus added to the problems? Battery acid ate through the connection of a cluster of wires at the positive terminal.

The car has been feeling sluggish lately ... does this air pump have any bearing on that?

2004 was a terrible year for my car (79,000 miles now)... replaced both cv joints replaced an inner tie rod replaced a wheel bearing replaced engine mount bushings unfixed so far- passenger door handle is jammed pending - this air pump issue

In the interest of keeping this thread going...

I keep getting the SAS Malfunction code as well, but I can't bring myself to replace the $300 blower for the following reasons:

1) The light never comes on at startup or during the first two minutes of driving. It usually comes on after the car is warm and has been running for 15-20 minutes. I'm under the impression that the SAS pump only runs for two minutes at startup, so why would it kick off a code so much later?

2) I can feel/hear the pump running for the first couple of minutes after startup so I know the motor's not burned out.

3) The light only comes on once a week or so, not every time, so I know the motor's not burned out.

So perhaps I have a wiring problem that occasionally wiggles itself to simulate a fault?

Can anyone tell me what exactly triggers the fault, i.e. what electrical signal indicates a fault? Is it the current draw on the SAS pump motor? Is it the O2 sensor level at startup?

My Haynes manual only dedicates one sentence to the SAS system, acknowledging its existence, and it doesn't appear on the schematics.

Thanks,

-RL

The computer has no reliable way of sensing if the air pump is working at cold start. So, it's tested after the car is warmed up. When you come to idle, sometime after the car is warmed up, the computer stops adjusting the mixture and monitors the front oxygen sensor, then turns on the air pump system. If the oxygen sensor does not report more oxygen in the exhaust within a few seconds, then it believes there's a problem with the air pump system.

These test conditions may not occur in every trip you take, and if the A/C comes on, or the throttle goes off idle, the test is aborted. 2 aborts and the computer won't try to retest until after the next cold start.

If your pump is running, chances are it doesn't need to be changed, no matter how noisy it is. In addition, there is a solenoid valve that needs to open to allow engine vacuum to open the SAS valve. And of course the purple vacuum hose between the solenoid and SAS valve has to be OK. The wires can come off the solenoid valve, something can go wrong with the vacuum supply, and the SAS valve can be seized closed.

On my '98 V70 the pump has been noisy for more than a year, and still works fine. The SAS valve would not fully close, so I changed that last year when I first noticed the pump noise. On my '98 S70, the pump was dead (burned out motor, seized shaft) when I bought it in '02. Also the SAS valve was seized closed. A friend with a '98 V70 had a noisy pump in the fall, I counselled him to ignore it after letting him hear mine, but his was dead within 2 weeks.

If battery acid gets anywhere, it's going to wreck things. Air pump failure has no symptoms other than the check engine light.

So, what's my best approach to the fixes now? Replace both the valve and the air pump? How would I know if both need replacing?

$295 - air pump $86 - valve $5 - clamps and gasket

Yikes

How safe is a $175 used air pump? If this part is often a problem, it's not a safe bet, right?

If this part is in short supply at FCP Groton, and the Volvo part is $400, would you go the used route? Would it be safe to wait until FCP gets the part?

Thanks, Mike mikechiu AT overlunch DOT com

In the "main fuses" box are 2 yellow relays. Pull the one furthest from the fender and jump the 2 larger terminals and see if it runs and pumps. Note that the air pump draws a lot of current, a thin jumper wire will get hot enough to burn you almost immediately and the ends of your jumper will weld to the terminals. If the pump runs, it won't need to be replaced, at least not right away. The SAS valve is simply a vacuum valve. It should be sealed tight when no vacuum is applied to the small vacuum connection, and open when vacuum is applied. If it won't seal tight, then it needs to be replaced.

I wouldn't chance a used part unless it was a lot closer to free than $175. Not fixing this immediately will only cause annoyance from the check engine light, and if you have another problem, you won't know about it. The air pump not working will not cause any other consequential damage. Under the battery is an electrical connector for the air pump, disconnect it from the car harness or just leave the relay out if it's not working.

I took another look inside the car today when it was bright outside. The black rubber where the purple vacuum line meets the SAS valve is in bad shape. Do you know if the rubber serves as a hose or if it's just protection for the vacuum line connection. If it's a hose, then that is obviously the place I should start.

Can this vacuum line be replaced without replacing other things? Where does the other end lead?

Thanks. Mike

That elbow does indeed carry vacuum, so you need to replace it (it's available separately) and if you're lucky that will be your only problem. The purple vacuum line goes under the distributor and ends up at the solenoid that is mounted on the fan shroud. From the solenoid you can follow the other vacuum line to the intake manifold.