alextnecc

2000 s4 tip
I am seeeing the 17831 and 17819 errors in vag-com and doing a search I see many have seen this with a Flow too low. I am seeing both these errors with a flow too high.

Has anyone every seen this ? Any ideas ?
After clearing the codes I can usually drive the car for a few days before the error is repeated. Suddenly the error will come up when the car is started. Usually after the 3rd time cold starting...

Any ideas would be appreciated....

Bracketracer

Output testing or readiness monitor generation?

Secondary air systems are relatively easy to diagnose on these cars. If you're getting the code on both banks, which it looks like you're getting, then normally you can rule out the combi-valves.

So, the first thing you should do is an output diagnostic test to find out if the 2nd air pump is actually running. If it is, then you have either a pressure hose leak or a vacuum source leak.

alextnecc

Wouldn't both those errors show a low pressure problem and not a high pressure problem ?

Bracketracer

that I have in the Bentley manual. Is it the Vag-com that's saying flow too high, or some other information system that's saying this?

P1411
17819
Sec. Air Inj.Sys.,Bank 2

Flow too low 2)
- Check fuse for secondary air injection pump
- Check vacuum hoses
- Check piping from pump to secondary air injection valve (Combi valve)

Repair Manual, 2.7 Liter V6 5V BiTurbo Engine Mechanical, Engine Code(s): APB, Repair Group 26, Exhaust system, Secondary air injection system

P1423
17831
Sec. Air Inj.Sys.,Bank 1

Flow too low 2)
- Check fuse for secondary air injection pump
- Check vacuum hoses
- Check piping from pump to secondary air injection valve (Combi valve)

Repair Manual, 2.7 Liter V6 5V BiTurbo Engine Mechanical, Engine Code(s): APB, Repair Group 26, Exhaust system, Secondary air injection system

alextnecc

My bad its flow to low. I'm gonna get into the car and replace a bunch of hoses and vacuum test all the stuff under there... Soo many hoses soo little time.

Bracketracer

can you hear large volumes of air hissing out anywhere? If not, then yeah, you either have a 2nd air vac solenoid problem, or more likely, a vacuum hose leak.

alextnecc

I don't hear any hissing but I really haven't had a chance to check it out in depth. Perhaps monday night I will get a moment. I think that I will have to replace a bunch of older hoses. I think that I will just get in there and replace all or as many of the lines as I can. Does this sound like a good idea ? Any suggestions for upgraded line to use ? Should I use some silicone based hi quality stuff?

Bracketracer

when the 2nd air pump is running, then yeah, you're probably looking at a vacuum problem.

As far as the type of hose to replace the existing ones with, I tend to use the factory 3.2x1.9mm cloth braided stuff, but that's just me.

Careful when you're trying to get those hoses off of the various solenoids and vacuum tees, since the plastic is likely very brittle at this point, and will have a tendency to break, as I've found out more than once.