Hey fellas and ladies, im looking to eliminate the EGR and the AIR pump system on my trans am, as far as removing the components ive got that handled but now my question is how do i keep the check engine light from coming on now that there deleted. If any one has any info on how to do this please post a link, if there is someone that has documented the whole procedure with trouble sooting tips and such,great. thanx for your time

 

Either you can turn it off via PCM tune or you can just plug the EGR solenoid up and leave it disconnected from the EGR and manifold. You can buy vacuum port caps from any auto parts store. They come in an assortment of sizes.
You only need to block off the EGR port on the back of the intake. You do not have to block off the EGR exhaust pipe-to-intake passage (located on pass. side/rear of intake). Easiest way is find a LT4 blockoff plate if possible. Or you can buy a gasket, trace the pattern onto a piece of aluminum and cut it out.

 

I thought the pcm would come into play, do you know of how you would go about deleting them from the pcm, i do have access to a GM Tech scanner, i would thing that you would have to reprogram a new vin into it or a reflash but in order to do so i would have to know what to enter. Any Idea where i could find that?

 

What year is your car? It affects the answer to you question, particularly with regard to the PCM, codes, and fittings required to block off the AIR ports. Not all years of the LT1 are the same.

Why not add a "signature" showing basic info about your car - year, model, trans and any major mods are usally the minimum? That way people can provide you with more accurate answers.

 

Sorry about that guys i have been meaning to post that but i never got around to it. My car is an 95 LT1 Trans Am Automatic.

 

The motor is out of the car at the moment, ive got an eagle 383 stroker assembly MSD opti spark distributor, Pro race series crane cam roller rockers, Moroso oil pan, edlebrock headers high flow cat, flowmaster muffler, 2800 stall converter, edlebrock 52mm throttle body.

 

Since you have an OBD-I PCM, all you need to do is unplug the harness connector from the AIR pump, and make sure the fuse in the circuit is good. You will not get a code. The EGR diagnostic in OBD-I is not very sensitive. About 75% of the people are able to delete the EGR system and not get a code. That's the code for EGR flow (DTC 32). You also have to avoid the code for a missing EGR solenoid (DTC 27). To eliminate that, you measure the resistance of the solenoid, and put a resistor of similar value in the pins in the harness connector.

You will not notice any performance increase, other than what reqults from the minor weight reduction. The systems do not operate at WOT.

 

Thank you sooooo much ive been trying to get that information for a long time, as far as the HP gain or lack there of im just looking to clean up around the engine for my own satisfaction. Thanx again on for your time and patients, well done.

 

Just one more thing, with the air pump you said to leave a good fuse in for it, what about the relay should that be left in as well? Oh and do you know anything about eliminating or substitutes for the MAF?

 

Leave the AIR pump relay in, too.

If you want to remove the MAF (I guess you have some reason), you will need to get a speed density tune.

 

Is there any downside, other than increased emissions, to removing the AIR & EGR? I'm planning to get non-emissions headers, and remove my AIR & EGR also, which is why I'm curious. Are there places that sell block off plates for the two EGR connections at the rear of the intake manifold, or do people just fab something up?

 

You can get block off plates from:

http://www.sjmmanufacturing.com/

The AIR pump runs for about 3 minutes at start up to help the cat heat up faster. That reduces the heavy emissions of the rich start condition. After that is shuts off and isn't used again.

EGR is used to quench (reduce) combustion chamber temperatures under operating conditions that cause high temps, causing increased formation of NOx. Typical condition would be lugging the engine up a hill at low RPM in the wrong gear. Reducing the combustion temps also reduces the liklihood of detonation (knock) under those operating conditions. EGR does not operate at idle, does not operate above 3,500RPM, and not at WOT.

 

Thanks much for the info. Unfortunately, I have a couple more questions.

So, which part number would I need for just an AIR & EGR delete? SJM-1001? I'm assuming the EGR plate would block off where the EGR valve attaches to the manifold and the Intake Plate would block off where that pipe attaches to the rear of the intake more towards the passenger side of the engine?

Or would I need one of the 3 plate kits that include the exhaust plate? What is the exhaust plate?

I'm also going to check out the for sale section here.

Also, is there any upside to this other than cleaning up the engine bay and not recirculating exhaust gases through the engine?

Thanks again.

Edit. I may have just answered some of my questions by reading the product descriptions again. Is the exhaust plate used to seal up emissions legal headers after an EGR delete?

 

So about the MAF delete you say i would need a "speed density tune" is this just a flash for the ECM or is it a chip? Could you give me a little info on how to get and use them? Thanx alot for your time

 

BTC cars that have factory manifolds the 3rd blockofplate would go to the exhaust where the tube from the back of the manifold attached to the exhaust.