vacuum line problem??
 

1993 Camry 4Cyl....250K miles..

took some time today to clean the throttle body and the vacuum lines out with carb cleaner today. saw some posts that this would help the notorious rough idel problem the toyota's seem to have...

I've done everything else imaginable and recommended over time from this forum to smoothen the idle as much as possible with as many miles as it has (clean EGR, temp sensor, OX sensor, cleaned injectors, full tune-up, spark wires, cap and rotor, done other things I can;t remember at the moment...you name it!). it seems to be pretty good now, but never smooth as when it had only 100K miles...

Question...
there is a row of three vacuum line pin connections on the top part of the TB just above the connection for the big air intake tube. looking at these three pin lines from the drivers side, I removed the small vaccum rubber hoses and sprayed carb cleaner in all three, noticing that the carb cleaner spray came out the other side in the throttle body from only two of them. Spraying into the far left connection, the spray didn;t seem to go anywhere (this is one of the 2 lines that would run from the TB to the EGR Valve modulator)

here is a link to see a picture of the vaccum line diagram. You will notice the vacuum line to the EGR modulator that is labeled with the letter "R" that is the one I'm asking about...

http://opc.mr2oc.com/online_parts_ca...m_diagrams.pdf

Spraying carb cleaner into the far left vacuum pin connection, should I see the spray come out into the throttle body? or does it run somewhere else?

just wondering if this would help the rough idle improve more...
Brian

One of the TB ports going to the EGR exits on the engine side of the throttle plate, perhaps you are not seeing the fluid when the plate is closed.

thanks toyomo...

I thought that being clogged might have been my issue, but it turns out I found a vacuum leak on one of the hoses to the vacuum switching valve. very hard to get to being on the back side of the engine, but replaced the hoses and decided to connect it to the firewall instead for easy access next time around!

thanks!