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Does anyone have directions on removal of the air pump. I don't even know where it is.:smokin:
 

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Sorry to dig up an old thread. Any adverse effects from removing it?
Right now I'm looking at the TSP long tube headers and thye do not have the EGR fittings in the headers. Will the removal of the EGR and Air pump have any negative effects on the engine?
 

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Sorry to dig up an old thread. Any adverse effects from removing it?
Right now I'm looking at the TSP long tube headers and thye do not have the EGR fittings in the headers. Will the removal of the EGR and Air pump have any negative effects on the engine?
Short answer, maybe.

Detailed answer requires that you understand what the Secondary Air Injection System is. Here we go.


The Air Secondary Injection (AIR) pump on the C5 is designed to lower the exhaust emission levels after engine start up.

The Powertrain Control Module (PCM) commands the AIR pump relay ON, by supplying a ground to the relay control circuit. This action energizes the AIR pump which forces air (oxygen) into the exhaust stream. The PCM also commands the AIR vacuum solenoid valve ON, by supplying a ground to the control circuit of the AIR solenoid. With the AIR solenoid activated engine vacuum is then applied to the AIR shut-off valve. Freash air from the AIR pump then enters into the exhaust stream. The air that is introduced into the exhaust system accelerates catalysts operation reducing exhaust emission levels. When the AIR system is inactive, the AIR shut-off valve and check valves prevent airflow in either direction.

The system includes the following components:

The AIR pump relay-- The AIR pump relay supplies high current to the AIR pump voltage supply circuit. The PCM commands the AIR relay ON by suppling a ground on the control circuit of the relay. This action closes the internal contacts of the AIR relay, energizing the AIR pump.

The AIR pump--The AIR pump supplies fresh air through the secondary air injection system into the exhaust stream. The PCM supplies a ground for the AIR pump relay. Battery voltage is then applied to the AIR pump. The inlet filter is the only serviceable part of the pump.

The AIR vacuum control solenoid--The AIR vacuum control solenoid controls the AIR shut-off valve. When the AIR system is enabled, the PCM supplies a ground to the solenoid. This enables the solenoid, allowing engine vacuum to be applied to the AIR shut-off valve.

The AIR shut-off valve--The AIR shut-off valve is vacuum operated. When the AIR system is enabled, engine vacuum is applied to the valve. The vacuum opens the valve and allows air from the AIR pump to flow to the check valves. When inactive the shut -off valve prevents airflow in either direction.

The check valves--The check valves prevent back flow of exhaust gases into the AIR system. A shut-off valve that has become inoperative, shows indications of exhaust gases in the outlet port, or heat damaged hoses may indicate a check valve failure.

The Pipes/Hoses--The pipes/hoses carry the air from the AIR pump to the exhaust stream. The pipes/hoses can be tested for leaks using a soapy water solution. With the AIR pump running, bubbles will form if a leak exists.

Results of Incorrect Operation

The PCM detects a system airflow problem by monitoring the heated oxygen senors (HO2S) and Short Term Fuel Trim (FT) values during normal open loop system operation. This is called a passive test. If the passive test indicates a pass, the PCM takes no further action. If the passive test fails or is inconclusive, the PCM diagnostic will proceed with an intrusive or active test. The PCM will command the AIR system ON, during normal closed loop operation and under normal operating conditions. This is called an active test. The active test will pass or fail based on the response from the HO2S. A lean HO2S response indicates that the AIR system is functioning normally. An increasing Short Term Fuel Trim value also indicates a normally functioning system. The AIR diagnostic consists of the combination of the passive and active test. It requires failure of the passive and active tests on two consecutive key cycles to illuminate the malfunction indicator lamp (MIL) and store a DTC. If the PCM detects that the HO2S and Short Term FT did not respond as expected on both of the engine banks DTC P0410 sets. If the PCM detects that the HO2S and Short Term FT did not respond as expected on only one of the engine banks DTC P1415 bank 1 or P1416 bank 2 sets.

If incorrect voltage is present on the vacuum control solenoid or the pump relay control circuits the device will not operate. This will be detected by the control module, and DTC P0412 for the solenoid or P0418 for the relay sets.

The following DTCs can set if a secondary air injection fault is detected:

P0410-- A system flow problem has been detected.
P0412--A vacuum control solenoid control circuit problem has been detected.
P0418-- A pump relay control circuit problem has been detected.
P1415--A Bank 1 flow problem has been detected.
P1416--A Bank 2 flow problem has been detected.

From all that, I can tell you that doing so will cause the MIL to illuminate and codes to set. There are other things that will be affected also, but I don't know if they will affect the performance of your ride. That annoying MIL indication is enough to make me not even think of doing this. It just makes your car look like a piece of crap (at least in my mind).

My suggestion? Leave it alone unless you design engines for a living.
 

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Like Junkman said, if you just go and remove everything you're going to set codes. However, you could have it all tuned out and then there really isn't cause for concern. Most of the guys I know have done this, including me on my "other" LS1.
 

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Junkman, thanks for the write up. Lots of useful info there.
Its my understanding that the Air system shuts off soon after start up and only cuts down emissions until the cats heat up, which is why they are there in the first place. Since it is my plan to get Long tube headers with no cats and a cam, I'll be in need of a tune and will have the Air tuned out, among other things.
I don't plan on taking the Air system off till I do that though. And that's not till late spring early summer. Just getting all my research in. Thanks to all for the info.:buhbye:
 

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Think long and hard about removing the cats from the system. I kinda wish I hadn't done that. For the small gain in horsepower, you might be kicking yourself when inspection rolls around. The way that emissions are being watched, it's only a matter of time before most if not all modern vehicles will need visual, sniffer, etc. I'm fortunate enough now to know people that do it for a ;)
 

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I doubt that you would pass an emissions test without that thing so if you live where they do testing, I wouldn't mess with it either. I agree with PSU in that the horsepower gain will be very minimal.
 

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Ohio has no emissions test what so ever but I'm sure the TSP long tube system could be fabbed up to accept cats if needed. If not I'll probably go with the LG Streets.
 

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Ohio has no emissions test what so ever but I'm sure the TSP long tube system could be fabbed up to accept cats if needed. If not I'll probably go with the LG Streets.
I guess it depends where in Ohio you live. I live in Lorain county and have to get the e-check done every 2 years !
 

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I live down in Columbiana County. The only thing we have to worry about is a visual inspection in the event we get pulled over.
 

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new member question

I agree with the Junk man. my passenger side check valve has been down for at minimum 50 thousand miles.I recently learned the secret about a dic message ground fault detected.Its the after market alternator i got from parts america. or is it a bad key switch lock. I will know soon. I just purchased a Valeo on eBay wit the original part # reconditioned for $109.00. Im praying it does the trick. this is a constant pop up on my 2001 z06. Question? will a slightly old battery as long as I make sure its fully charged before i in stall the right alternator be OK?
 
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