Fixing my egr system, all the vacuum lines have been chewed by rats. Looked at this diagram for reference.



Since the egr solenoid connects to the old charcoal canister, which I no longer have because I switched to the plastic style tank. Wondering how to run vacuum lines to get a working egr system as well as a working charcoal canister (I dont have the gas tank's canister hooked up to the intake for vacuum at this time)? Thanks for reading!

 

Nobody?

 

No EGR experts on deck????

 

The purpose of the charcoal canister is to filter the gas vapors so anything hat may leak out will not cause human harm. as you can see in the diagram the egr solonoid is hooked to under the throttlebody to a ported vacuum signal. Then to the solenoid and onto the egr valve. The ccp solenoid is also tied into this ported vacuum signal. If your tank looks like this you might try wiring up the solenoid on the tank and run a hose to t-into the ported signal. The gas tank will need to vent to prevent vapor lock. I dont know the ohms of the solenoids or there duty cycle so you might have to try it to see if it works.

 

I hope I have answered your question but im not really sure what your asking about the egr

 

So the two systems are not dependent on one another in any way? GM just decided to tie both systems together and to not drill a second vacuum hole for the charcoal canister? The new ls1 tank doesnt require two vacuum sources? I can just route the one under the tb to egr, and the one on the side of the tb to evap?

 

Correct. EGR is one system (Exhaust Gas Recirculation). Gas tank vapor collection and purge is another.

Correct. A rubber "T" fitting is cheaper than drilling and pressing another fitting into the throttle body.

Correct. Just one. To further note: Third gens had the charcoal can (vapor collection) in the engine compartment. Due to lack of underhood space in the 4th gen, the can was moved back to the gas tank. You can use the third hard line (vapor line, vs the supply and return) as your vacuum source to get from the engine, back to the gas tank.

Probably. The 3rd gen can shares the small ported vacuum line with the EGR, which looks like a control circuit. But, it also has the large "suction" line to purge the vapors caught in the can. This wraps around from the passenger side of the TB and runs to the charcoal can.