Northstar Engines and System Technical Discussion Discussion, EGR removal on 1997 seville w/ northstar? in Cadillac Engine Technical Discussion; I was going to remove/replace the egr valve on my 1997 seville and there are only two bolts....one is easy ...
EGR removal on 1997 seville w/ northstar w/ss fuel rail?
I was going to remove/replace the egr valve on my 1997 seville and there are only two bolts....one is easy to take out, the other i removed the nut only to find the other nut/bolt(i am not sure how it comes out yet) blocked by the stainless steel fuel line brace...i don't want to break anything so i was hoping for some help. does anyone know how to do this or do i need to remove something else...thanks for the help. btw, i was thinking of trying to clean up the old one as this was recommend by a buddy at the chevrolet place...is that good advice....thanks again.
Yes it has...i am sorry i didn't mention that....i just recently noticed i needed to. I am going to edit my first post to mention that. thanks. i hope i don't have to take it to the dealer for this job.
It would be easiest to remove the fuel rail first. 4 bolts in the center, then you just kinda wiggle it out. You don't have to remove the fuel lines or anything, just move it out of the way so you can get to the EGR stud. When you put it back in, make sure all the o-rings are on all the injectors, and line everything up, and pop all the injectors back into their holes. Then button it down. Go easy on the torque, it should be just a little over hand tight. Shouldn't take you more than 15 minutes.
Remove the four acorn nuts that hold the engine cover in place. Then remove the engine cover. Two stud-bolts fasten the EGR valve in place. The forward stud-bolt utilizes a hex-nut to fasten the fuel lines retention tab. Remove the forward nut from the base of the EGR valve. If you were removing the old plastic fuel rail for EGR access you would now pull the tab off the stud and remove both stud-bolts and then the EGR valve but when removing the EGR with the S/S fuel rail in place it takes a few more steps. The S/S fuel rail is very rigid which makes it necessary to lift the rail along with the attached fuel injectors up out of the intake manifold. To remove the S/S fuel rail pull up on the two purge line retainers at the forward stud-bolts remove the large plastic line that connects the throttle body to the front valve cover, remove the rear plastic PCV line and then the four fuel rail retention stud-bolts, now pull up on the fuel rail one side then the other maybe a 1/2” at a time until the assembly is free (the fuel injectors and wiring will remain attached to the rail). Since the rail is all one piece including the fuel lines retention tab at the EGR valve, the forward stud-bolt becomes accessible upon the S/S fuel rail removal. Now remove the two EGR stud-bolts and the EGR valve.
There are other threads you can search as to EGR cleaning. I removed and cleaned mine three times twice when the plastic fuel rail was in place and once with the S/S fuel rail in place. I ended up replacing the EGR because after three cleanings it still set a P0404 code.
I included a picture of my EGR valve to give you an idea of the location of the pintle valve. The valve, shaft and its corresponding seat are what need cleaning to remove the carbon deposits. I used throttle body cleaner along with a small acid brush to aid in the cleaning. They say the rule is to always keep the EGR valve upright (as installed on the engine) while cleaning to avoid damage to the electrical parts in the upper part of the unit.
Reinstallation of the S/S fuel rail is the reverse order of the removal but make sure the retention tab is on the forward EGR stud-bolt as you seat the injector/rail assembly into the intake manifold. When installing the four long fuel rail retention stud-bolts make sure the threads are clean and dry. Tighten these four stud-bolts to 71-inch/pounds then and additional 120 degrees. Reinstall all lines, recheck your work and if all looks ok start the engine and check for fuel ad vacuum leaks. If everything checks out ok, stop the engine and install the engine cover (tighten the four acorn nuts to 106 inch pounds).