EGR Diagnostic Switch
Thread Starter
Melting Slicks
Joined: Apr 2003
Posts: 3,110
Likes: 6
From: Red Sox Nation! RI
EGR Diagnostic Switch
For the life of me, I can't find this SOB. Manual says it's a dark green wire back near the distributor. Can I get at this switch w/o pulling the plenum? TIA
Pro
Joined: Nov 2005
Posts: 602
Likes: 0
From: North Bay Ontario
I'm in the same situation (85 L98, with iron heads)...I can't find a tube coming from the exhaust manifold to the EGR. Yes, the ERG valve is nicely hidden under the plenum but for the life of me, I don't see a tube going to it. Does anyone have a picture or diagram? I just got the car last year and don't have access to previous owners to find out what they did. I'm wondering though, if my exhaust manifolds have been changed and the tube didn't get installed...
Thread Starter
Melting Slicks
Joined: Apr 2003
Posts: 3,110
Likes: 6
From: Red Sox Nation! RI
Benny, thanks. I'll check that tomorrow. I'm guessing you mean the pipe with the ugly *** heat shield on the passenger side. I saw that, it just didn't match the service diagrams I had and the color code was wrong.
Pletz, I could try and e-mail you copies of the diagram, but I've already found a few errors in them. Location of the EGR solenoid is one.
Pletz, I could try and e-mail you copies of the diagram, but I've already found a few errors in them. Location of the EGR solenoid is one.
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
On my 86E my EGR pipe is deleted and the ends that go to the intake manifold and exhaust manifold are blocked off. The single dark green wire in question is located in the wiring harness out of the firewall next to the distrubitor more to the pass side. You might have to dig through the wires to find it. I was searching around after replacing my intake manifold gasket and ran across this wire and wondered what I forgot to connect. Then realized it was for the EGR pipe switch that I don't have. The EGR only has one vacuum going to it and that's all. The EGR solenoid located under the TB/plenum has a two wire connector and three vacuums that connect. When trying to service the EGR or solenoid it is best to remove just the plenum, so to have full access and not screw anything up. The dark green wire is just taped to the harness wires and does not throw a Code 32.
Drifting
Joined: Feb 2006
Posts: 1,423
Likes: 96
From: Magnolia Tx
C4boy,
The switch pigtail is black wire. It plugs into a green wire [its usually is green] hidden down by the dist. hold down bolt area.
Pletz, Your heads incorporate the egr passage. The switch screws into the egr valve base directly. Its hard to see, and the plenum has to come off to change it. good luck to you both
The switch pigtail is black wire. It plugs into a green wire [its usually is green] hidden down by the dist. hold down bolt area.
Pletz, Your heads incorporate the egr passage. The switch screws into the egr valve base directly. Its hard to see, and the plenum has to come off to change it. good luck to you both
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Drifting
Joined: Feb 2006
Posts: 1,423
Likes: 96
From: Magnolia Tx
Glad to help. I've had to do this to both my cars. One of each style. The plenum is not very hard to pull off. Intimidating the first time. Use good quality torx bits. The lower end stuff can mess up the bolts. If it doesn't pop out pretty easy, you probably missed a bolt.
Pro
Joined: Nov 2005
Posts: 602
Likes: 0
From: North Bay Ontario
Since I will have my plenum off, to change the EGR temp sensor, it would seem like a good idea to clean my EGR valve while I've gone that far. Any tips on cleaning the EGR valve, presuming that when I vacuum test it, it tests out okay.