Secondary Air Injection Pump; Troubleshooting Questions...

[chris22104]

Ok, so I'm pulling up the code for the secondary air injection pump. Checked it, and it is not running at all, and has not been. I know it isn't supposed to run all the time. The service manual says when fully warmed up, it should turn on about 20 seconds after start up, and run for about 5-10 seconds. No-go. Trouble-shooting starts. First, 12 volt directly to the air pump; it blows just fine. No noises at all, bearings, nothing, just perfect full force air, as it should. The air pump itself is fine. Second, the correct fuse on top of the battery. Perfect, tested with ohm meter too. Good continuity. Not the fuse. Third, the relay. Pulled it and checked with 12v and ohm meter, the relay is definitely good. Fourth, jumped the 2 main leads that the relay plugs into (crosses the current over when the relay is closed.) Pump blows strong and is fine. So, the next step is, what? The smaller 2 leads (that open and close the relay) go to the ecm and ground, right or wrong? Continuity check in order, but where do these 2 wires from the relay, that dissapear into the wire loom go to? Thanks guys....

[cep]

I thought it ran after a cold start, not a hot start.

Seems to me that a)the ECM is failing to send the signal, or b) the ECM is getting an erroneous signal that the engine is always warm. (coolant temp sensor?)

At any rate, what is the downside of it not running?

[gforce1108]

See if there is anything in here that might help you:
http://www.newbeetle.org/forums/showthread.php?t=31906

[chris22104]

The Air injection pump will not run AT ALL, hot or cold, no matter what. The service manual says it should run after fully warm, start the car, and within 20 seconds, it should go on for 10 seconds or so. That's right out of the service manual. I'm pulling an 0411 code. The car runs fine, but I have to fix it in order to get the car to pass inspection. Again, any input from anyone in the know on where the smaller leads from the relay go (one to the ecm and the other grounded?), in order to check their continuity? Thanks again!
PS: thanks for the lead to the article, but it still leads me to believe what I already know; it in the wiring that closes the relay, or in the ecm itself. Anyone? anyone? Buehler? Buehler? anyone?

[cep]

OK, we got a conflict between your service manual and mine (Bentley).

From page 26-16 of Bentley:

The secondary air injection (AIR) system on the APH gasoline engine uses an air pump to inject fresh air behind the exhaust valves for approximately 100 seconds during cold starting.

Specification
1.8L: Engine coolant temperature for secondary air injection on initial start up.....5-33 deg C (41-91F)

2.0L: Engine coolant temperature for secondary air injection on initial start up.....15-35 deg C (59-95F)

Then it goes on to say:
Also, after each subsequent engine start (up to 96 deg C (205F) max engine coolant temperature), the seondary air injection system will, after a 20 second delay, switch in for 10 seconds during idle and is then monitored by the system.

So I was wrong. It does run on a hot start, but only for 20 seconds and after a short delay.

What does your service manual say about cold starts?

[chris22104]

My manual says the same as yours (I have the 2002 1.8 Turbo S.) Nonetheless, the pump will not run at all, no matter what or when, unless bypassed, as explained above. So my question remains about the 2 wires to the relay that send the signal to close the 12v to the pump...where do they come out, so I can do a continuity test on both the leads? They disappear into the looms. I guess there really isn't going to be a simple answer from anyone who has diagnosed these signal wires in the same situation. I suppose I'll just have to get in there and get down and dirty to track them down....If I can locate the ends of both leads and they test good for continuity, the problem must be in the ecm itself. Simple process of elimation. But if that ends up being the problem (the ecm,) then what??!! I'm not shelling out a thousand on this car, that's for sure....

[Vatchy]

Did you ever find out what the problem was? I'm having the same problem with my wife's 2001 Turbo.

[TanitaA25]

I am having this issue now! New Beetle owner! pump works but no volts making it to the pump.