2.3 Egr?.........

[Bryan22]

next tiem you should plug/unplugg in the opposite directions and see if milage is consistant with dpfe unplugged or with direction of travel.

 

[Duane867]

If you clear the computer and start driving again with out the EGR in place wouldn't the computer relearn new patterns and adjustments ? OR is it actually hard programmed in a chip ?

 

[Sidewalk]

Holy thread resurrection!

 

[kimcrwbr1]

I always wondered how the egr helped lower the temperature in the combustion chamber it makes sense now by displacing the oxygen in the air fuel mix it wont burn as hot at least that is how I understand it. And when you think about it it amazes me how the computer can control the pulse of fuel through the injectors to get the precise amount of fuel when running at 3500 rpm it must be in like micro seconds

 

[chasracer]

A tip for the original question. Make yourself a block-off plate from a piece of sheet steel or aluminum. If you can remove the egr without tearing the gasket up, you can even reuse it.

 

[Sidewalk]

I always wondered how the egr helped lower the temperature in the combustion chamber it makes sense now by displacing the oxygen in the air fuel mix it wont burn as hot at least that is how I understand it. And when you think about it it amazes me how the computer can control the pulse of fuel through the injectors to get the precise amount of fuel when running at 3500 rpm it must be in like micro seconds

Injector opening is usually measured in milliseconds.

 

[Duane867]

If you clear the computer and start driving again with out the EGR in place wouldn't the computer relearn new patterns and adjustments ? OR is it actually hard programmed in a chip ?

Any one ?

 

[zekew64]

If you clear the computer and start driving again with out the EGR in place wouldn't the computer relearn new patterns and adjustments ? OR is it actually hard programmed in a chip ?

Actually, it's both.

I say this because, from the factory, there are what is known as "baseline parameters;" that is, what every system in a vehicle (especially an EFI vehicle) is set to do, so that the vehicle will run from the factory.

Once you drive a certain amount of mileage (I've heard anything from 15 miles to an equal amount of mileage for a full tank of fuel), then the computer starts to "learn" how you drive to keep your driving style as close to the factory specifications as possible, as well as compensating for things like uphill and downhill driving, as well as stop-and-go driving.

Basically, the computer learns how you drive to keep the vehicle as close to the baseline parameters that are set from the factory, and thus, the fuel mileage that was expected from the factory.

On the other hand, when you block off the EGR and then reset the vehicles ECU (the car's "brains") you force it to learn to do things that can, as has been stated, be detrimental. You might get more power out of your truck, but at what cost? In my mind, and nobody has brought this up, if you disable the EGR, what are you actually doing? Where do the exhaust gases go? They would go to the catalytic converter. Given enough time, without an EGR system, the catalytic converter will clog--and when that happens, your car becomes a ticking time bomb, because the converter being clogged will sooner or later force the backpressure in the exhaust back through the engine and cause an engine to literally explode from the pressure buildup.

At least, that's from the mouth of my auto instructor when I was going through my first year in college.

 

[Wicked_Sludge]

Your instructor is full of shit.

The PCM is continuously writing to the adaptive tables to maintain a given air-fuel-ratio under given conditions. It doesn't start or stop doing so at any particular mileage.

Disabling the EGR will have no effect on your cat converters. The tiny amount of exhaust gas that would have passed through the intake (and back out the exhaust port) just goes out the tailpipe along with the rest of the vehicles exhaust.

What kills cat converters is vehicles running rich for long periods of time. The cat converter will burn the un-burnt hydrocarbons sent to it by the motor causing it to run very hot (think: throwing gasoline on a camp fire). Eventually the sustained high temperatures will cause the substrate to melt and break down.

A clogged cat converter will strangle an engine. Volumetric efficiency drops off causing a loss of power and poor running. The more clogged the converter is, the worse the motor will run until it simply cannot pump any more gas through itself and stops running. A clogged cat cannot blow up an engine.

 

[Mark_88]

Holy thread resurrection!

Your instructor is full of shit.

Well, if that's what it took to get you to come back I'm going to look through and resurrect a few more to get other long time MIA members to show up on here...

How you been??? I think your last post was just a few years ago~

 

[Wicked_Sludge]

Well, if that's what it took to get you to come back ...

Just couldn't take the "he said she said" misinformation in that post. It made me twitch.

All has been well. I haven't really been gone...just occasionally lurking on the boards. I respond to any PM's or e-mails I get so I'm not hard to get hold of

 

[Mark_88]

Cool~!

Someone was asking where you'd gone and I suggested to send you a PM...that was only about a year ago...good to see you're still alive and kicking...

 

[Wicked_Sludge]

Makes me feel all warm and fuzzy inside to know I was missed!

I've missed you guys too. TRS is an awesome community. If there were more hours in a day I would probably have the time to be active again but you know how life is...

 

[Sidewalk]

Well, if that's what it took to get you to come back I'm going to look through and resurrect a few more to get other long time MIA members to show up on here...

How you been??? I think your last post was just a few years ago~

 

[zekew64]

Your instructor is full of shit.

Really? Do you even know how a cat even works? According to your own words, you don't:

The PCM is continuously writing to the adaptive tables to maintain a given air-fuel-ratio under given conditions. It doesn't start or stop doing so at any particular mileage.

Disabling the EGR will have no effect on your cat converters. The tiny amount of exhaust gas that would have passed through the intake (and back out the exhaust port) just goes out the tailpipe along with the rest of the vehicles exhaust.

What kills cat converters is vehicles running rich for long periods of time. The cat converter will burn the un-burnt hydrocarbons sent to it by the motor causing it to run very hot (think: throwing gasoline on a camp fire). Eventually the sustained high temperatures will cause the substrate to melt and break down.

A clogged cat converter will strangle an engine. Volumetric efficiency drops off causing a loss of power and poor running. The more clogged the converter is, the worse the motor will run until it simply cannot pump any more gas through itself and stops running. A clogged cat cannot blow up an engine.

While I do agree with you that a cat will clog a car, causing it run poorly and then to quit, you, sir, fail to understand why.

Do you even have a basic concept of chemistry, to understand the process?

The catalytic converter does not "burn" what goes through it; there is no combustion or ignition within the catalytic converter itself. The reason why a catalytic converter feels warm is from the heat of the exhaust, first of all, which was produced in the engine itself; the second reason is that, during a catalytic conversion of CO and NOx to nitrogen, carbon dioxide, and water, there is a conversion that takes place that also includes a rise in temperature that the catalyst is, itself, unaffected by (catalyst: a chemical compound that acts as a reagent during a chemical reaction that is itself unaffected by that reaction).

While the high temp sustained in rich-running cars will cause the catalyst to eventually melt and break down, in a properly running system, this does not happen. Rather, the heat from the exhaust gases themselves, whether or not the system is operating correctly or not, is what causes the substrate to melt and clog the system.

As to your first statement, if that were the case, why did he show me pictures from the shop he worked at where a customer had to have an engine replaced, due to a piston blowing out of the motor because the cat had gotten clogged? In essence, the way he explained it to me is that the pressure blew out the piston with the highest compression through the oil pan, with all the other seals and gaskets still holding, just like you have the same results when you have a coolant system failure--wherever the system is weakest at, the pressure will blow at that point first.