Egr Solenoid Rebuilding? (Page 10/10)
Kitskaboodle OCT 17, 09:58 PM
Patrick, my cat is a brand new, California certified cat. Not even 50 miles on it.
EGR valve and O2 sensor are also brand new.

On a different note, I performed another test today that you all might find important:
I decided to do a manual vacuum test on two Fiero V6 egr valves, one brand new and one that I removed from my 86 GT with about 10K-15K miles on it. Both egr valves were sitting on my workbench for this test. With my MightyVac vacuum gauge, I slowly applied vacuum to each egr valve. As I did this, I observed the pintle begin to retract upward. I noticed that it would travel upward as you applied more hg’s of vacuum. (yes, I know this is an obvious statement) Anyways, I determined that both egr valves were “fully opened” only after hitting about 5 1/2 to 6 hg. Less hg, less open, etc…
The point is (and yes, I’m assuming here) that in order for the egr valve to allow exhaust gases to re-enter the egr tube/intake manifold, it has to significantly open for the whole egr process to work, correct?
If so, my other point then is that the egr valve needs to get 5 hg of vacuum from a vacuum source. So maybe the MightyVac book reference of 5 hg minimum is correct.
Kit
P.S. I see Notorio’s point about going to a different shop but I had already paid them $50 even though it failed. Re-tests are only an additional $10 dollars.
Kit
Patrick OCT 17, 11:38 PM

quote
Originally posted by Kitskaboodle:

I determined that both egr valves were “fully opened” only after hitting about 5 1/2 to 6 hg. Less hg, less open, etc. The point is (and yes, I’m assuming here) that in order for the egr valve to allow exhaust gases to re-enter the egr tube/intake manifold, it has to significantly open for the whole egr process to work, correct?



I don't know if it would be correct to make that assumption. It's possible the EGR valve opens far enough to have the required effect at whatever "low" vacuum (within factory specs) is being directed to it by the EGR solenoid.

I do know for a fact that the 2.8 (or probably any engine) will not run properly if the EGR valve is “fully opened” at all times, as I experienced and reported Here.
Notorio OCT 18, 02:11 PM

quote
Originally posted by Kitskaboodle:

Patrick, my cat is a brand new, California certified cat. Not even 50 miles on it ...

Kit



Kit, another recommendation I found was that New Cats should be run for at least 100 miles in order to fully burn off the protective coating they come with and that before 100 miles they won't be fully operational. Perhaps others will comment on if this is important or not.
Kitskaboodle OCT 30, 03:07 PM
I found this egr troubleshooting chart in my FSM. (see attached)
In the top left area of the page there is an instruction to remove the double vacuum line that goes to the egr solenoid vacuum port nipple, then rotate it & reconnecting just the egr valve side, then hooking up a vacuum gauge to the manifold side egr port, (on the egr solenoid) then turn the ignition switch to ON, then apply vacuum and then egr valve should not open. Well, when I apply vacuum with the vacuum gauge and start pumping, it will not apply vacuum no matter how hard I pump the vacuum gauge. I did this same test on my 86 GT (which has no known egr problems) and the results were the same.
Am I doing something wrong?
Kit
Kitskaboodle OCT 30, 05:27 PM
While I was doing some additional testing, I reconfirmed (again) that A) the vacuum line that goes from the underside of the throttle body to the egr solenoid (manifold side) is good and has no leaks. I also reconfirmed that the vacuum line that goes from the egr valve to the egr solenoid (the port that has a tee junction on it) is good also and has no leaks.
Kit
Mike in Sydney OCT 31, 04:23 AM
When you replaced your EGR valve did you replace the orifice plate? When I purchased a replacement for mine the instructions said something about matching the orifice plate to the engine. There were several orifice plates with different sized holes. I'm guessing they allow different amounts of exhaust to be recirculated which could change the emissions readings
Kitskaboodle OCT 31, 11:33 AM
Yes, I used the orifice washer that is stamped number 11. You have to “peen” it on all 4 sides.
Kit
Kitskaboodle OCT 31, 09:42 PM
Ok, I might have made some progress today. (Here’s why)
There is a thread I saw here on the forum and it’s been on my mind. The thread raised the question about the egr tube gaskets as far as which one goes on the plenum side and which one goes on the egr valve side. As you may know, one has a restriction and one doesn’t. Just to confirm, I called Steve at the FieroStore and he said the gasket that has the smaller opening goes on the intake manifold side and the bigger opening gasket goes on the egr valve side.
So…… because I recently put on a new egr valve, I recall doing the opposite. I took my egr tube off and yes, I can confirm I put the smaller opening gasket on the egr valve side. Here is a pic of the parts on my workbench in just the order I put the egr tube on.
Kit

[This message has been edited by Kitskaboodle (edited 10-31-2022).]

Kitskaboodle OCT 31, 09:54 PM
To further ponder on this smaller orifice gasket…
I did order some extra egr tube gaskets from Rockauto and they are the “normal” big hole version. (See pic)
So, where do you get this special smaller orifice hole version?
What if I ran both sides with the bigger, normal gaskets? Maybe this might fix my high Nox issue?
Any Calif. guys run both ends that are the normal size? (No orifice restrictions)
Kit
Kitskaboodle OCT 31, 10:00 PM
As a side note, I had not really focused on my pcv valve in a long time. I took it out today and found out that, though it would rattle when shaked, it was quite gummed up and I could still blow a little air through it. Shame on me for overlooking this.
I ordered two tonight..
Kit