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P0411, replaced combi and saip, help!

6K views 14 replies 7 participants last post by  onepoint8tee 
#1 ·
Okay so I threw a P0411 code, secondary air insufficient flow blah blah. My combivalve was bad, and my saip was full of water. I bought a new valve and pump from rreyes. Had it put in, code came back. Im not hearing any sort of jet engine like im supposed to.if the pump is turning on. Besides the pump being bad.. anyone have any other ideas?
 
#5 ·
It only sounds like a jet engine when it's failing really, otherwise it sounds like a higher pitched radiator fan for the first 30 seconds of idle, from ONLY a cold start. Have someone else turn on the car, while you stand in front of the car with the hood up. You're listening around the airbox area for the pump to turn on (sounds like a vacuum cleaner), in fact an easy way to tell is to remove a corrugated black hose from the front of the airbox (it snakes down under the airbox where the pump is, you should be familiar with what I'm talking about) and see if it is sucking air. When it cuts off it sounds like a vacuum cleaner turning off (this will be after about 30 seconds.) If the pump is sucking air, and turning on, you have a vacuum leak, or clog, somewhere in the lines that go to the engine, more black corrugated plastic pieces to play with.

Here's the before mentioned hose coming off of airbox:
Auto part
 
#11 ·
airbox hose part number

It only sounds like a jet engine when it's failing really, otherwise it sounds like a higher pitched radiator fan for the first 30 seconds of idle, from ONLY a cold start. Have someone else turn on the car, while you stand in front of the car with the hood up. You're listening around the airbox area for the pump to turn on (sounds like a vacuum cleaner), in fact an easy way to tell is to remove a corrugated black hose from the front of the airbox (it snakes down under the airbox where the pump is, you should be familiar with what I'm talking about) and see if it is sucking air. When it cuts off it sounds like a vacuum cleaner turning off (this will be after about 30 seconds.) If the pump is sucking air, and turning on, you have a vacuum leak, or clog, somewhere in the lines that go to the engine, more black corrugated plastic pieces to play with.

Here's the before mentioned hose coming off of airbox:
View attachment 3863
do you have a part number for the hose in the picture your provided? i can't find it on ecs
 
#7 ·
The relay is highly suspect if it's never been replaced. The contacts are just barely big enough for the pump (blower)--my relay contacts were all burned up after 10 years.

A meter can be had for under $10 at Harbor Freight, etc, and you can get a pretty decent one (for auto repair, at least) for under $50.

The SAIP doesn't run immediately after a cold start. Rather, it runs after the engine has started to warm up a little. It runs for 100 seconds for the 1.8T, not as long for the V6. This behavior makes it hard to troubleshoot. If you have a VagCom, there's an SAIP test function, but otherwise...

My suggestion is to access the relay (373), in the ECM box. You can check the 40 amp fuse while you're in there. You can use a wire to jumper the relay contact terminals (30 & 87) in the relay socket and the pump should run--but remember it pulls 20 to 30 amps, and there will be quite a spark when you remove the wire. My preference is to unplug the relay, remove the cover (it snaps off), plug it back in, then use a tool to push the contacts closed.

Either of these methods will apply power to the SAIP, so the SAIP should run. You don't need the key in--the fuse is straight from the battery. You will be able to hear the pump run since everything is nice and quiet--it sounds like a small vacuum cleaner. If you want to pull the hose off somewhere upstream of the combi valve you can feel air blowing, too.

I suspect you'll find the relay contacts are very pitted and worn down.
 
#9 ·
A replacement relay will plug right in. Your CEL will go out, probably after the first cold start cycle (absent other faults).

The VW part number is 4H0 951 253A, but most any 4-pin 40 amp relay will work. It's a very standard automotive relay. The VW relay has a resistor across the coil in the relay as a surge suppressor, but others on the forum have used relays without the resistor. BUT--Don't use relays with a diode surge suppressor, as they could damage the ECM. You're most likely to find the plain relay at auto parts stores, maybe sold as a "Euro" relay. The VW part is about $25 at ECS Tuning; a generic Chinese relay is probably $10 or less.

Some tips on getting to the relay: the ECM is in front of the driver (except in Great Britain) beside the brake fluid reservoir (under the plastic cover) in a nice black plastic box. It's cover is held on with 5 bolts: 3 are easy to get to, 1 requires a ratchet, and 1 requires a long, skinny extension... Park the wipers up and remove the plastic plug near the driver's wiper arm pivot--your long, skinny, extension goes in there. If you lose that plastic plug a new one will cost you about $3 (ask me how I know). (Credit to VW there--yes it was $3, but I had that unique part in two days.)
 
#12 ·
I bought my 04 1.8 with p0411 already on can't seem to figure this out either, I also get the jet engine on startup. I'm at the point where I'm about to drop it off at the local shop. :banghead:

I havent had a chance to make sure with a full tank but it seems my mpg is suffering a little, could something connected with P0411 be responsible for that?
 
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