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-   -   EGR (https://www.nopistons.com/2nd-generation-specific-17/egr-6238/)

1Revvin7 10-12-2002 09:02 PM


Originally Posted by dac' date='Oct 12 2002, 08:49 PM
[quote name='alton316' date='Oct 12 2002, 10:29 PM']I dont know how they tested it, does anyone know of any addetivies that

i can put in they might help clean out some of the carbon?

If so maybe i can give it a try before i tear it apart.

No additives will help if it's clogged. It is outside of the combustion chamber. The only thing that runs throught it is exhaust which is thick black carbon. My honda wouldn't pass due to the EGR and it was fully blocked. I put chucked up a CHOKE CABLE to the end of my drill (ala: rotor rooter style) and fed it down the EGR hole until I got it cleaned out.



I never have understood the Mazda EGR, because it is on TOP of the motor. So I'm not sure where it gets it's Exhaust from to feed into the intake.



[/quote]

i think there is a hole on the exhaust manifold where it is fed to, atleast thats what i saw when i took my manifold off.

alton316 10-16-2002 12:15 AM

well, went to a differant smog shop today, passed no problem.

and i didn't change a thing . looks like the guy at the other shop

was trying to rip me off.

isamu 10-16-2002 02:11 AM

Good to here you passed. Too bad about the other shop.

pengaru 10-16-2002 03:50 AM


Originally Posted by dac' date='Oct 13 2002, 01:49 AM
[quote name='alton316' date='Oct 12 2002, 10:29 PM']I dont know how they tested it, does anyone know of any addetivies that

i can put in they might help clean out some of the carbon?

If so maybe i can give it a try before i tear it apart.

No additives will help if it's clogged. It is outside of the combustion chamber. The only thing that runs throught it is exhaust which is thick black carbon. My honda wouldn't pass due to the EGR and it was fully blocked. I put chucked up a CHOKE CABLE to the end of my drill (ala: rotor rooter style) and fed it down the EGR hole until I got it cleaned out.



I never have understood the Mazda EGR, because it is on TOP of the motor. So I'm not sure where it gets it's Exhaust from to feed into the intake.



FROM THE NET:

EGR has been successful in reducing NOx in gasoline engines. When an engine uses EGR, a percentage of the exhaust gases are drawn or forced back into the intake, at the direction of the engine's electronic control module (ECM), and mixed with the fresh air and fuel the engine is ingesting.



The purpose of using EGR is to lower the peak flame temperatures inside the combustion chamber. Forcing some exhaust back into the cylinder slightly reduces the concentration of oxygen and slows the burning a bit, making things a little cooler. EGR also absorbs heat, further cooling the process.[/quote]

There's two small port holes in each exhaust port sleeve, you may have noticed them before, they are clearly visible in this photo of my S5 turbo rotor housing exhaust port:

http://pengaru.com/~swivel/cars/rx-7...2/IMG_1656.JPG

the exhaust gases travel through those holes, into a passage inside the rotor housing which goes down then out to the intermediate and end housings (similarly to the way the water flows) then goes up to small ports below the intake ports on the end and intermediate housing... this particular engine is an S5 though so theres no EGR. However, if it were an S4 I believe there's a passage on the intermediate housing that goes from this same passage up to the EGR... I don't have pictures of that though. There are also holes below the exhaust ports but those seem to go from the manifold to the same passage the holes in the sleeves lead to... and are usually blocked by headers... The exhaust passages exist to bring exhaust to the intake manifold (lower) for the ACV which is also usually removed and blocked off for headers.... (this is why the ports still exist on the S5 even without EGR, it's still needed for the ACV).



I've been trying to find a source for replacement exhaust port sleeves that don't have the holes but I have not had much luck... Since I do not have ACV or EGR on my motor.



hope that helps https://www.nopistons.com/forums/pub...IR#>/smile.png Damn, that camera can take some decent pictures when it feels like it, maybe I should read the manual.

j9fd3s 10-16-2002 11:55 AM

actually i think it migh be the bottom 2 holes under the port, when you put an 89 turbo on the manifold bolcks off the egr



mike

pengaru 10-16-2002 02:28 PM


Originally Posted by j9fd3s' date='Oct 16 2002, 04:55 PM
actually i think it migh be the bottom 2 holes under the port, when you put an 89 turbo on the manifold bolcks off the egr



mike

When I was tracing the passage back from the holes under the intake ports air was exiting out of the holes in the exhaust port sleeve and the holes under the exhaust port. If you block off the holes under the exhaust port with a header or turbo manifold, those holes in the exhaust port sleeve are still bring exhaust gases to the passages. Odds are though you've probably blocked off the ACV And EGR anyways (or didnt have EGR to begin with). The gases still go to the intake manifold though with the ACV blocked off which I imagine can't be good for intake air temps, hot exhaust sitting in your LIM.

j9fd3s 10-16-2002 02:49 PM

yeah but i dont think its that bad either. do remember that on my 88 t2 with 89 turbo that the egr didnt have any exhaust gas going to it. but with the stock turbo it did.



mike

evilT2 10-17-2002 12:45 AM

hey man, you can have my old egr if you want to pay for shipping. i cant gurantee that the thing works properly, cause im not really sure that it did to begin with, but since there are no emissions around here i dont have to worry about it.

anyway, it would be a start.

alton316 10-17-2002 08:29 PM

dont need 1 now it passed

dac 10-18-2002 10:59 PM

Nice picture! Thanks for clearing that up. I wondered why I didn't see any EGR hoses like most cars have.


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