strange egr setup

[j_tomo 0]

well mr bmws got me scratching my head again

i got sick of the noisy air-con pump/ idler so i flicked the belt off (i doesnt get warm enough to need it down here!)

while i were under there i notticed a pump unit that looks like a aircon pump (with a clutch on the front an all)

as fas as i can tell it pumps exhaust gases into the intake or vise versa

the jappas use a steel pipe with a vacuum opperated valve on one end

any one got any ideas?

cheers

jerm

[CamB 48]

I believe its EGR - the exhaust gas helps it provide a nice lean reading for emissions (even though it is BS).

[Lubed 55]

Yeah its a fresh air pump, it takes air from the intake and pumps it through the head into the exhuast ports from cold start up to help the cats work faster therefore lowering emissions.Later generations use a electric pump.

[no-coast-punk 0]

If the air pump isn't functioning correctly the cat's WILL get clogged up and fail prematurely. Especially if the car doesn't see extended high speed driving sessions.

It's best just to live with the noise and put the belt back on.

[Lubed 55]

If the air pump isn't functioning correctly the cat's WILL get clogged up and fail prematurely. Especially if the car doesn't see extended high speed driving sessions.

It's best just to live with the noise and put the belt back on.

Interesting theory on the cats blocking, how did older cars with cats that never had a air pump in the system get on?

[j_tomo 0]

cats??????

lol mine have been replaced with those turbo muflers

this is the first ive heard of using a pump to swap inlet and exhaust

sounds like someone in bmw was making a job for themselves designing things that dont need to be

----oh yay a low emission super car-----

its all good today we had the hotest day this season that i could remember

16*c

thanks