intake manifold & egr testing (1 Viewer)

[poomasta]

So...first posting here. Bought a 94 FZJ80 about three weeks ago (112k mi), CEL came on one week ago, started reading this board voraciously...turns out to be code 71, ordered FSM from CDan, started testing EGR components yesterday...

but i don't really know what i'm doing . I'm not mechanically inept, but i've never worked on an auto before now. Following the FSM's "egr system inspection" steps, i made it down to step 5 (page EG-186: Inspect operation of VSV and EGR vacuum modulator with hot engine) before i got stumped. Apparently I am supposed to run a hose from port R of the egr modulator "directly to the intake manifold". I know where port R is and i know where the intake manifold is, but where exactly is this hose supposed to attach to on the manifold? I fear this is a dumb question, but I'm at a loss here

Also, general question about gaskets...the FSM points out some "non-reusable" gaskets on the EGR valve and the air intake chamber. do i really need to replace these if I'm just removing the part for inspection?

thanks...

-mike

 

[Beowulf]

I know where port R is and i know where the intake manifold is, but where exactly is this hose supposed to attach to on the manifold? I fear this is a dumb question, but I'm at a loss here

Mike,
You'll see several small nipples on the intake. Run a hose from one of them to port-R. When you rev it you will get vacuum.

Also, general question about gaskets...the FSM points out some "non-reusable" gaskets on the EGR valve and the air intake chamber. do i really need to replace these if I'm just removing the part for inspection?

The EGR valve has a metal gasket that you probably can reuse. I strongly recommend getting new gaskets because you just may drop the used EGR gasket down in the bowels of the intake, never to be seen again.

-B-

 

[poomasta]

Beowulf,

THanks for the help, but I'm still not entirely clear here...

You'll see several small nipples on the intake. Run a hose from one of them to port-R. When you rev it you will get vacuum.

The intake appears to have 4 nipples in close proximity. Three of them are labeled as P, R, & E (I don't see any notation on the last, slightly larger nipple). The R & E ports both connect to the egr modulator (via a couple hoses and some metal tubing). So i COULD connect port R on the modulator to port R on the intake, but that seems like i would only be bypassing the metal routing tubing...which i assume wouldn't make any difference....so, i'm probably not understanding you correctly...

i could post a pic if that would help illustrate my question...

thanks again
-Mike

 

[poomasta]

If I'm trying to test that the EGR valve responds to the vacuum from ports E & R, couldn't i just bypass the EGR modulator (go straight from port E on the intake to the egr valve) and ensure a warm engine @2500rpm runs rough when the vacuum opens the egr valve and send exhaust gas thru? As for the VSV, where does it intervene? At the egr modulator or at the valve? I assume it could control/restrict vacuum from the egr modulator which would in turn keep the valve from opening(?)

thanks
-mike