I have been referring back and forth to the Rotary Aviation video and one thing they show during the tear down is that the exhaust gaskets are to be positioned so that the holes are to the rear of the engine. Now on mine, the rear gasket had the hole to the rear, the front had the hole to the front. Upon inspection I see that the only one that matters is the rear, as that port feeds that strange little tube-thing in the exhaust manifold. Question: What does that port and tube do?

 

Anyone? This port feeds a steel tube that exits in the exhaust manifold.

 

EGR?

 

Is it for air coming from the ACV / Air Pump or exhaust to the EGR?

 

Wouldn't be for the air pump. It's source is from the intake pipes and the only other line is to the cat.

 

If I am looking at my shop manual correct it is labeled as EGR Switch (California Only) and it looks like a hose that comes off the EGR. It is on page F-125 of the 1993 Workshop Manual. I got the manual from Mazdatrix.com.

 

hey ryburg, since my car is originally a cali car, is the cali ECU tuned different and would I benefit more from removing emissions than say a non cali car ?

 

Holy beJesus! I've been meaning to get a service manual soon, but for $111.54 + shipping???? Why so expensive?? Are there any cheaper manuals out there, or is this THE ONE to get? Sorry Baja, not trying to jack your thread, just one of those things I noticed .

 

Ray Crowe at Malloy will get it way cheaper than that. 1-888-533-3400 or 703-490-8170

 

either that or download it for free!!! If you need a copy i can donate it to you.

 

It is for your EGR.

 

EGR it is then, it sounds like. Thanks for the replies!

 

Well, than a better question is for the people who have diabled thier EGR, do I need to have that hole opened with the gasket or can it be covered?

 

I have a question about this port also. I have a large amount of oil coming from my exhaust manifold when I try to turn the motor over and it seems to be coming out of this hole. Can anyone tell me why oil would be coming out of this? I really have no clue how this could happen unless I have a major internal crack in a housing or something. I thought that since I recently converted my turbos to non-seq that I probably put them back together wrong, but there is no evidence at all on the turbos of any kind of oil leakage, so its not coming from that side of the exhaust. I also have my oil injectors plugged and I premix, so the oil isn't coming from there either. Is there any explanation for this other than a bad internal seal?

 

It doesnt matter, you can just leave it alone -- the Mazda gaskets have the hole for it already but it wont effect performance having it there. When you remove the EGR from the intake that removes the system so nothing else needs to be done.

It is possible you have a lot of oil blowby from your turbos... how oily is the inside of your intake? I'd replace the exhaust manifold gaskets in any case as it should be atleast sealed but oil blowby shouldnt be that noticable unless your turbos are very tired...

~Kris

 

No oil at all inthe intake tract. That is why I dont think it is from the turbos. Also, on the exhaust side there is nothing really discernable to be oil. When I removed the manifold itself, there was oil residue all around that little hole under the ports.

 

Nobody has any clue? Please guys, I'm pretty much stuck right now because I think I may have to rebuild it. Anybody have any idea other than that?