tom0261

Still trying to get CALIFORNIA smogged. 1988 NA

My EGR valve operates correctly (confirmed), but it fails the smog check test. This test involves applying vacuum to the valve, with the result supposed to being rough idle or stalling. My guess it that the EGR passage from the exhaust is plugged.
Any ideas on how to roto-router (no pun intended) it clear with the least amount of disassembly and replacing of gaskets?
I image that the most effective approach is to remove the exhaust manifold and work from there, but I've gotten to the point where I can remove and replace the intake (to get at the EGR valve) in about an hour, and i don't have to crawl under the car or replace the gaskets every time.

HAILERS

I've a suggestion other than the ones I gave you before.

TAke a look at your rotor housings. Look to the left of centerline of the rotor housings. Centerline being.........middle.......top middle. About three inches to the left you should see a stamped F on the front rotor housing and a (you guessed it) a R.

I'm fairly sure you can see the F on the front housing without removing much of anything. The Rear might be a little more difficult.

Why am I suggesting this????? Simple. The Front and Rear rotor housings are different. Some people look at 'em and can't tell the difference. Most of those people seem to be in the rotor engine rebuild business in my Humble opinion.

What is different is the passages for the air from the ACV to the exaust ports and in YOUR case the passage in the ROTOR housing that feeds the intermediate housing where the EGR rests.

IF a Front rotor housing is put in the rear spot, there is now NO passage for the exaust fumes to the EGR. Simple as that.

Or? Perhaps someone installed the exaust manifold gasket on *** backwards and now there is no access hole to the rotor from the exaust manifold for the EGR. I'm talking those two small holes below the exaust ports. The exaust gasket covers three of the four small half inch holes. There should be a hole in the exaust gasket for that single passage. Cover it up and the EGR gets no exaust gasses.

Or the EGR might not be opening fully to let exaust air pass from the VERY LARGE hole in the intermediate housing to the TWO VERY SMALL HOLES fhat go to the intake passages in the intermendiate housing.

tom0261

Thanks for your help.

I did confirm that the fromt rotor has an "F", but , like you said, the rear rotor marking is not visible with everything installed. I will confirm later, but I don't have any reason to believe it is other than an "R".

For that matter, I have no reason to believe there to be any other installation errors, as, when I bought it two years ago, it passed smog check then, in Orange County, CA.

Also, I have pointed out before the the EGR valve and associated vacuum lines and solenoid valve, are operating properly.

So, my question remains, exactly how is this passage way routed through the housings, and how do I open it up (still assuming that it is blocked somehow)? It sounds like you're indicating that the exhaust gas flows through the ACV, but its not clear. I'd like to know if I can run something through it, starting from the EGR valve port down to the exhaust manifold? (I wish I had a spare engine to look at!).

tom0261

Turns out the exhaust manifold gasket was installed wrong, therefore blocking the EGR system exhaust port. Wonder how the previous owner got it smogged