EGR Block OFF?

[thehondardm]

Have any of u tried blocking off EGR on J32 or OBDII?
Pros?
Cons?
the only negative thing i see is that your timing wont be as aggressive, worth it blockin it?

[wolydotmatrix]

the only negative thing i see is that your timing wont be as aggressive, worth it blockin it?

What do you mean by this?
The EGR is only active at mild to medium loads.

The EGR system reduces oxides of nitrogen (NOx) emissions by recirculating exhaust gas through the EGR valve and the intake manifold into the combustion chambers. The ECM/PCM memory includes the ideal EGR valve position for varying operating conditions.

The EGR valve position sensor detects the amount of EGR valve position and sends it to the ECM/PCM. The ECM/PCM then compares it with the ideal position in its memory (based on signals sent from other sensors). If there is any difference between the two, the ECM/PCM cuts current to the EGR valve.

EGR Valve
The EGR valve is designed to lower peak combustion temperatures and reduce oxides of nitrogen emissions (NOx) by recirculating exhaust gas through the intake manifold and into the combustion chambers.

The main difference which IMO is minimal is that while the EGR is being blocked there will be a slight lean condition under is normal operation parameters. The ECM adjusts the injector pulse to accomodate the unburned fuel from the exhaust gas being recirculated (takes up space in the combustion camber).

My has been blocked for two years with no issues.

[thehondardm]

U right , but when u unplug egr, pcm thinks egr not working, meaning that temp is gonna raise and its gonna ping, so pcm reatards timing, sense part of the egr's job is to keep chambers temp down

[wolydotmatrix]

True but the EGR does not operate at WOT so temps are going to be there regardless. The lower combustion temps are for emissions not engine tuning.

[thehondardm]

egr is big emission thing and once chamber temps get over pcm gonna retard timing to prevent ping = poor performance

[wolydotmatrix]

egr is big emission thing and once chamber temps get over pcm gonna retard timing to prevent ping = poor performance

Iguess you answered your own question.

I will try this one more time.

When combustion temperatures exceed 2500 degree F., atmospheric nitrogen begins to react with oxygen during combustion. The result is various compounds called nitrogen oxides (NOX), which play a major role in urban air pollution. To reduce the formation of NOX, combustion temperatures must be kept below the NOX threshold. This is done by recirculating a small amount of exhaust through the "exhaust gas recirculation," or EGR. valve.

The EGR valve controls a small passageway between the intake and exhaust manifolds. When the valve opens, intake vacuum draws exhaust through the valve. This dilutes the incoming air/fuel mixture and has a quenching effect on combustion temperatures which keeps NOX within acceptable limits. As an added benefit, it also reduces the engine's octane requirements which lessens the danger of detonation (spark knock).

EGR is considered a `metered intake leak' and was developed to reduce the combustion temperatures to below 2,500 degrees, the threshold where NOx is created. Not unlike putting a brick in your toilet to lower the volume of water used, the EGR valve meters a readily available inert gas (actually exhaust gas which contains a lot of very inert Carbon Dioxide) into the combustion chamber to effectively reduce the volume. Smaller effective displacement means less fire, and less heat and thus lower temperatures, thereby controlling NOx emissions.

Obviously we don't want to `reduce' the volume of the combustion chambers (effectively reduced engine displacement) during hard acceleration, so EGR is turned off when you need full power (WOT (Wide Open throttle) conditions). At idle, the engine is very sensitive to air/fuel mixture ratios and swirl in the combustion chamber, so introducing EGR at idle is not on either. However at cruise the Fuel/Air mixture is set as lean as possible for maximum economy and this in turn generates the highest temperatures. All this being said the EGR will not affect WOT tunning

[JpowerVdub]

Quick question when yall say blocked... are you removing and disconnection the EGR valve as well? THanks

[thehondardm]

ya

[HickamHatch]

Here's how I blocked mine off

http://i32.photobucket.com/albums/d7/93civic96ls/J32%20Project/6847956f.jpg