Fixed my secondary air fault

[S2central.net]

I was getting intermittent faults (with MIL on the dash) for insufficient air flow in Bank 2 -that's left side for the uninitiated.

So... A quick look at the manual tells me there is vacuum controlled actuator on each bank at the back of the head. Both actuators are triggered by an ECU controlled solenoid.

The fault always pops up on Bank 2 so I know the pump and solenoid are good. I found the vac lines and followed them back to the actuator. The first touch of the hose where it meets a 90 degree rubber elbow into the valve and it breaks off. Ahah... That hose has been cracked and leaking enough to trigger the fault now and again.

So I was just able to prize off the elbow and remove the remains of the broken hose and had enough length to reroute it slightly and refit.

That *should* be that one sorted for now. If I ever get round to a remap then I shall be sure to ask for deletion of the secondary air system - it's a PITA.

[quattro-nick]

I assume this is about a v6 or v8 and not a 5 cil?

[S2central.net]

Correct - the old I5 engines never had any of this secondary air crap. Not exactly sure when it was phased in but the purpose is to heat up the CAT(s) faster by directly extra air into the exhaust flow following a cold start. Not sure how long the system runs for - it's a pure Eco thing.

[hunker7]

Correct - the old I5 engines never had any of this secondary air crap. Not exactly sure when it was phased in but the purpose is to heat up the CAT(s) faster by directly extra air into the exhaust flow following a cold start. Not sure how long the system runs for - it's a pure Eco thing.

Ah this, my dad's MK1 Octavia has it, and it's making some weird noises. Will be most likely removing the system altogether rather than replacing.

It's to warm up CATs as you said, thus ruching emmision

[S2central.net]

It's probably the air pump if it's making mad noises. If you delete it physically you will get an engine light - it has to be removed in ECU software.

If you have vcds you can easily run "output tests" which will activate the air pump - listen to that and see if it's the fault.

As a quick fix you can just unplug fuse for the pump but like I say you will get an engine light soon after.

[Monkeymagic]

The sai is a load of tosh. I used to delete them.on 1.8t all the time. Forge do a neat alloy blank so you can remove valves and all pipework. From memory you can fit a resistor to trick the ecu. I had one on a s3 where valve on head seized open and filled the pipework with moisture from exhaust.,at higher revs it was pushing water into the airbox and soaked the filter etc.

[S2central.net]

I don't think a resistor trick will work on the B6 because thats just on the N112 solenoid valve which sends vacuum to the mechanical valves which allow air into the exhaust - its the damn ECU and lambda sensors being smart and figuring out that if the signal is out of threshold during warm up then it knows something isn't right... there is no other way to measure SAI airflow per bank that I can see.

JHM, APR and others offer a V8 S4 ECU tune with SAI deleted. AFAIK - thats the only way to delete it properly on these cars.

[re2500]

I get a secondary air injection insuffiecent flow code occasionally on my B6 too.
Thanks for the pointer Paul, i'll check the vac lines!