Honda Prelude Forum banner

1 - 4 of 4 Posts

·
Registered
Joined
·
7 Posts
Discussion Starter #1
Ok here is a question for anyone...does unplugging your EGR really do anything for your car? Also How can you tell if your secondaries are unhooked as well? I think mine are but Im not sure, the guy that worked on it said he did, i just want to know how do you know?
 

·
New title is new
Joined
·
9,436 Posts
EGR:
At partial throttle it adds some exhaust gasses to your intake manifold to cool the combustion temps and lower nitric oxide (nitric acid) production.
At idle and at >25% throttle it is turned off.
No benefits to unhooking it at all, and some people report detonation resulting from disconnecting it (the ECU assumes that it can advance the timing more then the non-egr intake air allows)


Secondaries:
Look at the intake manifold, on your right side of it there is a brass UFO looking thing with a rod coming out the bottem and a vacuum line on top.

With the engine off, see if you can move the lever that the rod is attached to, if it's stuck something is messed up.
Start the engine, the UFO thing will suck the rod into it, and turn the lever like you were justing doing.
If you pull the vacuum line off the rod should pop back out and turn the lever.
 

·
Registered
Joined
·
1,243 Posts
Bobnova said:
EGR:
At partial throttle it adds some exhaust gasses to your intake manifold to cool the combustion temps and lower nitric oxide (nitric acid) production.
Maybe this is a typo but you said that it cools the combustion temps. I don't understand how that is possible. How can hot exhaust gas cool IM air or the combustion temps? Please elaborate.
 

·
New title is new
Joined
·
9,436 Posts
No typo, it cools the combustion temps by adding inert gasses, they simply won't burn, and act as a buffer to the combustion.

I don't know how often you build fires, but if you do it often you've probably noticed that if you stack the wood in such a way that it doesn't get good air circulation it burns very slowly, and with much less heat being produced.


If you'd like a longer more technical version let me know, and i'll see if i can dig up some papers on it.
 
1 - 4 of 4 Posts
Top