Air Pump Question

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Jul 10, 2002 | 11:13 PM

harley

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Air Pump Question

I have a 94 F-150 4x4 5.0L and recently installed headers with glass packs but no cats. There was a tube running to one of the original cats that it appears comes off the air pump up by the alternator. I am calling this an air pump cause the only thing I can see that it does it blow air out the tube. I am wondering if this can be removed from the truck? Does it serve any other purpose? Will I gain anything by removing it or only cause myself more problems?

Thanks for any help you can offer.

Bob

Jul 11, 2002 | 06:47 PM

topo4u2

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Joined: Jan 2002

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Air Pump Question

If the pipe you are talking about is the one I think it is an air pipe alright which comes off of the check valve at the rear of the engine. This air tube heads to the catalytic convertor to send air in it to aid in lowering the Oxides for emissions. If you have emission testing where you live, removing it could cause you some difficulty in passing testing but performance wise not a problem.

Jul 11, 2002 | 09:30 PM

harley

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Air Pump Question

Thanks Mike for the info. We do not have emission testing in PA yet so I can get by for now. I was hoping that the pump only served the cat. I can see the line run along the right side of the engine and then between the engine and firewall but I was not sure if it branched out to something other than the cat. Now I will have to be sure I can get a drive that will fit with the pump removed.

Thanks again for helping out.

Bob

Jul 12, 2002 | 07:46 AM

swirk

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Joined: Aug 2001

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From: New England

Air Pump Question

From what I understand, that air pump also aids in keeping the convertor cool enough to keep the ceramic inside from melting into one big blob. Without the air pump, your convertor will get cherry-red and possibly clog up. I heard this from a mechanic. I have removed my air pump, but have not witnessed the cherry-red convertor myself.

Jul 12, 2002 | 08:10 AM

winfordr

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Joined: Jan 2001

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From: Rural Florida Panhandle

Air Pump Question

The air pump furnishs fresh air to two places; exhaust ports at the rear of the heads, and to the convertor. This is accomplished by two different air diverter solenoid valves, controlled by vaccuum, between the air pump and exhaust ports and converter tube. Since you don't have converters you can probably just let the tube pump to atmoshpere. If you remove the pump, your o2 sensors will give you a false reading when the computer opens the solenoid air valve to the exhaust ports, because it will be expecting the oxygen content to change. You will probably get some check engine codes.

Winford

Jul 12, 2002 | 07:58 PM

HippieCustoms

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Joined: Jul 2001

Posts: 250

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From: South Carolina

Air Pump Question

Ok I'll tell ya how I heard it. The thermactor pipe going to the back of the head is there to pump air into the exhaust when the engine is cold. This will allow the o2 sensors to see more air and give more fuel , making the mixture more rich much like a choke would on a carb. Once it warms up alittle, the thermactor closes to the head and goes to the converter. The extra o2 is required by the catalyst in the converter to operate properly. If this is all so, removeing the air pump can do two things. One, plug up the converter, and two, make it alittle cold natured. I have had the pump off of mine for a while and have not had any noticable problems. I don't have any thermactor ports in the back of my heads and I removed the cats. I hope this helps and sorry it was so wordy. Good luck. Later, Hippie

Aug 14, 2002 | 07:46 PM

groundrat

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Joined: Jan 2002

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From: New Hampshire

Air Pump Question

If someone would be so kind as to clarify this for me I would appreciate it. I just installed a set of shorty headers. I have a 2 1/4 " dual exhaust kit for it as well that I am reluctant to put on because of all of this emissions junk. I am a resident of the great state of New Hampshire and they do not test emissions. Can I remove all of this stuff and not see the check engine light come on? Or should I have an exhaust shop weld that little pipe from the heads to the exhaust pipe? I will eventually put high flow cats on it, but only when required. Thanks in advance for your help.

Bill