air pump
Thread Starter
Intermediate
Joined: Jul 2017
Posts: 43
Likes: 3
air pump
hi,
recently I had my annual car check and it failed the exhaust smoke test.
I found out that the car has an air pump, which dilutes the smoke with air through the headers. Is it correct that the air it blows through the headers is sucked down by a tube coming from the airfilter box?my car has an aftermarket air filter. and the tube is plugged, see picture. is there a way to test if the airpump still functions? should i unplug the hose to see if it sucks air in? does the pump always pumps when the car is running or just on certain rpm's ? any information on the workings of the airpump system is much appreciated.
recently I had my annual car check and it failed the exhaust smoke test.
I found out that the car has an air pump, which dilutes the smoke with air through the headers. Is it correct that the air it blows through the headers is sucked down by a tube coming from the airfilter box?my car has an aftermarket air filter. and the tube is plugged, see picture. is there a way to test if the airpump still functions? should i unplug the hose to see if it sucks air in? does the pump always pumps when the car is running or just on certain rpm's ? any information on the workings of the airpump system is much appreciated.
Le Mans Master
Joined: Sep 2014
Posts: 5,278
Likes: 539
From: Kelowna BC
The AIR system draws air from the filter box and pumps it into the exhaust manifolds on cold start only to warm up the cats quicker. I think something else is causing your failure. Although the plug off could perhaps give a visual fail.
What else is not stock? Headers? Does it have cats?
What else is not stock? Headers? Does it have cats?
Thread Starter
Intermediate
Joined: Jul 2017
Posts: 43
Likes: 3
it has a K&N airfilter, Cooks headers (with the airpump intake manifold), and a cam, and high flow cats. so I understand the reason why it fails. just thought that perhaps fixing the airpump would make it a pass. couldn't, I just bypass the power wires to the airpump and make it pump continuously with a switch when going through the annual check? or would that mess up all sorts of sensors, which make the car run normal?
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so they test emissions in the tailpipe where you are located instead of the obd2 port?... ughhh
, if that's the case good luck getting it to pass with a cam
, if that's the case good luck getting it to pass with a cam
Thread Starter
Intermediate
Joined: Jul 2017
Posts: 43
Likes: 3
Acct Suspended APR 2026 by request
Joined: Dec 2010
Posts: 10,367
Likes: 1,272
2020 Corvette of the Year Finalist (performance mods)
C5 of Year Winner (performance mods) 2019
it depends where you live really, here in the states many places use the obd2 port on cars 96 and newer which makes things much easier
Acct Suspended APR 2026 by request
Joined: Dec 2010
Posts: 10,367
Likes: 1,272
2020 Corvette of the Year Finalist (performance mods)
C5 of Year Winner (performance mods) 2019
I don't think the people in charge really care when it comes down to it, it's basically all about money
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Le Mans Master
Joined: Sep 2014
Posts: 5,278
Likes: 539
From: Kelowna BC
it has a K&N airfilter, Cooks headers (with the airpump intake manifold), and a cam, and high flow cats. so I understand the reason why it fails. just thought that perhaps fixing the airpump would make it a pass. couldn't, I just bypass the power wires to the airpump and make it pump continuously with a switch when going through the annual check? or would that mess up all sorts of sensors, which make the car run normal?
Unsure what to say TBH... it's a tailpipe sniff for sure that failed it?
Thread Starter
Intermediate
Joined: Jul 2017
Posts: 43
Likes: 3
its almost time for the annual check, so I need to get things in motion. the above states that when the engine is warm, adding additional air wont help? but I would think it dilutes the smoke coming out, thus the test would read lower readings (particles per litres of smoke). anyway, if I would want the airpump to function by flipping a switch. how would I best get this done? get a + wire from the fusbox through a switch and hooked up to the red wire on the airpump?
Burning Brakes
Joined: Feb 2013
Posts: 904
Likes: 296
From: Sacramento, California
Running the air pump after the system has gone into closed loop won't change your emissions and "might" actually make it worse since the AF ratio will appear to be lean which causes the PCM to add more fuel which would most likely create higher emissions and more smoke. The air pump system only adds more oxygen during start up while the system is in open loop to heat up the catalytic converters faster to reduce emissions, but again only during a cold start up.
I would make sure your cats are in good working condition and maybe also do a tune up if it hasn't been done in a while. I would also run a bottle or two of some good injector cleaner through 1 tank of gas to clean the fuel system. Once you've done this try to find to one of those bottles of "garanteed to pass" emissions cleaners and run that through half a tank before you do the tailpipe test. It also helps to get the cats very hot before the test, so do some hard driving right before you go to test it. If all of this fails then your cam is just to big to pass a tailpipe test.
Steve
I would make sure your cats are in good working condition and maybe also do a tune up if it hasn't been done in a while. I would also run a bottle or two of some good injector cleaner through 1 tank of gas to clean the fuel system. Once you've done this try to find to one of those bottles of "garanteed to pass" emissions cleaners and run that through half a tank before you do the tailpipe test. It also helps to get the cats very hot before the test, so do some hard driving right before you go to test it. If all of this fails then your cam is just to big to pass a tailpipe test.
Steve
Last edited by killian96ss; Dec 31, 2018 at 10:45 AM. Reason: Added information