EGR System Testing and removal problems

[camrii]

A couple of questions for you guys who have maintained the EGR system in Gen 3 Camry:

1) I noticed that the EGR valve is connected to a long stainless steel pipe next to the intake header. Is this required for removal or is there an easier way without having to strip a lot of parts out?


2) If you look at the service manual for testing a EGR system, they want you to insert a SST tool into two terminal connections. Is the SST tool nothing more than to close the circuit? And what is its purpose in diagnosis?

3) When servicing the EGR system, is it usually recommended to replace all of the units (EGR Vacuum Modulator, EGR Valve) or is it ok to just replace the defective part?

Thanks.

[Doctor J]

If EGR system is plugged with carbon deposits, it is a good idea to clean all EGR ports, transfer pipe and a valve itself.

[Kep]

On my 90 Gen 2 the EGR valve lifts off of the long tube.

When you remove the valve it will be pretty obvious if it needs to be replaced ( Cleaning will probably work and it's cheaper but will require tenacity and delicacy. I ended up using a sharp pick to get out the carbon, carb cleaner didn't work very well). I don't remember mine having any electrodes to connect so I don't know about that. I would want to verify that the vertical tube is not blocked with carbon. Also, the rubber vaccuum tube from the bottom to the modulator on mine was clogged up and the port into the throttle body was clogged up.

While you're in the neighborhood you might want to go ahead and clean the throttle body and the IAC valve.

Kep