Secondary air pump delete

espritv8

Well-known member
Je crois que ici plusieurs l'ont fait. Je cherche un peu d'info / commentaires sur le fait de l’enlever. Apparemment, ce système ne sert pas a grand chose et cause plus de problèmes qu'il n'en règle.

J'ai lu que sur M5 E39, ça contribue a faire des dépôts de carbone au niveau des têtes. Est-ce la même chose avec la M3 E46?
Je cherche un bon DIY pour le M5 E39 (malgré que ça semble assez facile a faire) pour faire le delete, mais j'en trouve pas. Avez vous des liens a suggérer? Je veux être sur de rien oublier ou endommager.
Est-ce qu'il y a des contres indications à le faire? Ex: ne passerait pas l'inspection lors de la vente hors province / autres problèmes mécaniques?
Si le check engine relié a ce système a été retiré par un tune, est-ce que c'est nécessaire de l'enlever quand même, ou il devient inopérant, ou il continue a encrasser le moteur?

Merci!
 
Si tu lenleve faut tu le code sinon check engine.... Tu peux laisser la piece la et juste le coder ca va arreter de le faire fonctionner
 
Si tu es une personne vert garde le , si tu ten fou enleve le lol c'est juste une chose d'anti polution qui rebrule les gaz

Not quite right.
The EGR (exhaust gas recirculation) valve is used to reuse exhaust gases, the secondary air pump/injection (SAI) is used to pump fresh cold air after the exhaust valves to warm up the catalytic converters more quickly on cold starts, usually for less than 60 seconds.
 
And who do you think that make the EGR work? If the secondary pump dont work your egr don't do nothing...
 
They operate at different times and using completely different principles.

The EGR uses a mechanical valve which allows a small amount of exhaust gas back into the intake to improve combustion efficiency and reduce certain combustion byproducts.
The SAI uses an electric pump to take air from just after the air filter to pump it after the exhaust valves towards the catalytic converters and only for the first minute or so in cold engines.

Seems that the E46 and most new BMW petrol engines don't have an actual EGR valve even if the non-return valve used to protect the SAI pump motor is often called that way. This is a misnomer.

This is what an actual EGR valve setup should look like (notice the direction of the flow of air with the arrows):
exhaust-gas-recirculation.png

BMW does not do this.
 
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In short, you can safely remove it if you don't mind polluting more as was said previously.
You will most likely get a Check Engine light eventually unless your chip allows for the removal of the pump and skips the emissions testing.

This video really explains well what we have on most cars today:

Interesting stuff.
Bimmer_686 is not wrong though as the part you need to remove to bypass the whole mess is indeed known in many cases as the EGR valve. Its just the incorrect name for the part.
 
that's why I said if your not a green person delete it , because normally if you remove the secondary air pump is because you don't have any cats on.... don't make sense keeping this on if you try to heat something that's not there even the egr dont make nothing at this point ....
 
that's why I said if your not a green person delete it , because normally if you remove the secondary air pump is because you don't have any cats on.... don't make sense keeping this on if you try to heat something that's not there even the egr dont make nothing at this point ....

For the Air Pump, like you said, it defeats the purpose to keep it so delete it.
For the EGR, its a different story. Apparently its a good thing to have on older engines (even if you don't care about pollution). Of course, since we don't have a classic EGR system on 2000+ BMW petrol engines, its a non-issue.
If you're talking about that SAI/EGR valve, then you're right, delete it and put a cover plate on it. I think ECS has some.

From wikipedia:
A properly operating EGR can theoretically increase the efficiency of gasoline engines via several mechanisms:

Reduced throttling losses. The addition of inert exhaust gas into the intake system means that for a given power output, the throttle plate must be opened further, resulting in increased inlet manifold pressure and reduced throttling losses.[6]
Reduced heat rejection. Lowered peak combustion temperatures not only reduces NO
x formation, it also reduces the loss of thermal energy to combustion chamber surfaces, leaving more available for conversion to mechanical work during the expansion stroke.
Reduced chemical dissociation. The lower peak temperatures result in more of the released energy remaining as sensible energy near Top Dead Center (TDC), rather than being bound up (early in the expansion stroke) in the dissociation of combustion products. This effect is minor compared to the first two.
 
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