aajj1987

ok here it goes... I have a 1996 vette lt1 auto is their any way to remove the electric air/smog pump on driver front corner? if so what all do i need to do it? any information would be appreciated.

93-383

sure.. the only question is why? if you unbolt the pump remove the piping and plug the inlet to the exh manifld. to prevent a check engine light from comming on you need to install a resisor (I cant remember the ohms) in the connector to simulate the load of the motor. this way the computer dosn't think the pump has been removed or has a fault.

GT40_GearHead

here is a questioon:

what is the use of this air sistem ?

Strick

Emissions

BerniesVette

It pumps fresh air into the exhaust at the manifolds to dilute the exhaust gasses and provide more oxygen to ignite the air in the catalytic converters.
Bernie

GT40_GearHead

interesting...

but how does this not screw around with the A/F ration, the O2 sensors are also in the exhaust ???

MarkBychowski

The air pump only runs during warmup when the system is in open-loop (not using O2's), so there's no impact on A/F ratios.

Instead of using a resistor on the wiring harness, I reprogrammed the computer to eliminate the AIR pump test. This may cause problems with emmission testing though (if you need to worry about that) since you're disabling an OBD2 test. The resistor actually sounds like a good solution, though, if anyone knows how to do it.

Phil Ferency

Please.....more info on the resistor. I removed the AIR system from my 92 coupe and the "check engine" light remains on.

C4GUY

Reviving an old thread for my 1995? Is there an answer to the mentioned resistor in this. Seems easier than buying software. Want to clean up the engine compartment.

Though another thread I found said on a 1995, simply remove, cap the manifolds and no code will be set unlike on a 1996.

Any thoughts?

69427

My C4 is too old to have the electric pump, but unless you hear a more learned suggestion, how about just buying a potentiometer from Radio shack (50kOhm) and wire that up across the termials that powered the pump. Just keep reducing the resistance until the fault light goes out. (I'm assuming that the pump is monitored by an A/D circuit in the PCM.) However, if the PCM actually looks for some appreciable current (instead of just just checking to see if it's hooked up electrically) then you may have to put a decent wattage power resistor in there instead.

Just my speculation.

C4GUY

I am thinking the resistor would not work in that it would always be applying resistance. At some point the airpump shuts off shortly after start up and the computer is no longer looking for the resistance. The PCM at some point must go, OK, engine hot enough, O2 sensors heated up, turn off smog pump. If the ressitor was there it would almost act like it was always on.

At least I think so???

69427

While you're thinking, let me ask you a couple questions. Once the PCM turns the pump motor off, do you think the motor winding resistance just magically disappears? Second question: How do you think the PCM knows whether or not the pump is hooked up (or fell off after that last big pothole)?

PDQUIK95

On the 95,you can remove all the air pump/EGR piping and hoses and blank the manifold with no problem , but you do need to leave the EGR solenoid on the drivers side back of the manifold plugged in electrically in order for no code to be set. I did shut my air pump off with my software though because I decided to leave the pump in place and didn't want to hear it cycle. If you do decided to remove it without deprogramming it ,just tape the hot wire to the pump up good and out of the way. My 95 has been blanked off this way for 8 years now. No problems.
Rick

9T3VETTE

My 93 must be different. The EGR solenoid on the back of the manifold is still present and plugged in. Without the air pump a SES light was set and would run the cooling fans. This got annoying so I gutted the pump and put it back in with the connection plugged. It doens't make much nosie and the SES light went off at startup. However, after 15 minutes or so of drivng on the freeway I get an SES light for EGR. Still l havn't figured it out.

PDQUIK95

The 93 is different. Only the 94/95 can be done this way. The 95 being the last year of OBD1 makes many mods,removals, and tuning a little easier before the true OBD2 came in 96. Also things like removal of the rear O2 sensor for 94/95 without codes being set is nice unlike the 96 with the addition of a crank sensor and the requirement for 4 O2 sensors unless you use simulators for the rear sensors.
Rick

C4GUY

My intent was to say I am not sure how it works, help me understand, no need to get feisty.

9T3VETTE

Good to know thanks....any suggestions on getting the function tuned out of the ECM other than getting a tune made without the provisions?

69427

I used to design ECMs, PCMs and Ignition modules for a living. I don't throw out suggestions just to keep my typing skills from getting rusty. If my suggestions don't make sense to you please ask for clarification. I'm happy to go into additional detail if necessary. Conversely, my questions to you were an attempt to make you think about what's going on in your car, and help you arrive at a solution on your own if possible.

I assume we're both Corvette enthusiasts here.

C4GUY

Got it, well in that case, it appears at least on a 94 and 95 there is nothing triggered by simply unplugging it. But to continue my education then based on what you say and it does makes sense.

I would think (I am not certain) the ECM probably is looking for a load there, by measuring the current across a resistor (the pump iteslf if hooked up or a plug in resistor per your suggestion). So if that's the case, pump turned on or off then the resistance in the motor itself tells the ECM its there??

Of course this thread just confuses whether you can simply unplug it and move on

http://forums.corvetteforum.com/c4-t...-deletion.html

rickbraley

I am building a 383 for my 85 and like the idea of removing the air pump system if possible. Sounds like I can do this based on postings in this thread.

How will this effect the cat converter? The current system also appears to pump air directly to the converter?

Other than the pure mechanical aspect of doing this what exactly do I need to do to keep trouble codes from popping up?

I will be getting an upgraded PROM for the ECM so can this be handled then?

A quick summary would be fantastic!