The car is a 1986 automatic. Recently installed a set of Bosch GenIII's from FIC and now the car runs smooth as new. The hot start issue is no more as well. But now I am getting the SES light with a code 32 (EGR) when I run it a few miles at freeway speeds. If I clear the code and don't go on the freeway, it doesn't happen it seems.
Thanks to Agent86 I have the EGR section of the FSM and thanks to the member(sorry I can't remember the nick) with this link:http://www.geocities.com/jgkov/index.html, I have another write-up on the EGR system.
With what I've read, observed and tested, there are two ways the EGR code gets set: One is when the engine is started, the computer checks to see if the wire to the Temperature Diagnostic Switch is open or connected to ground. If it is connected to ground, the code is set. The other is after computed conditions have called for opening the EGR valve and a set period of time has elapsed and the Temperature Diagnostic Switch has not reacted to the hot exhaust gas passing by its probe on its way through the EGR valve and into the intake and has not closed its switch connecting the wire to ground, then this will set the code.
Although it seems bass-ackwards to me, and according to the EGR section of the FSM courtesy of Agent86, the EGR solenoid is energized by the computer to prevent vacuum from reaching the EGR valve when no EGR is called for and it de-energizes it to allow for EGR. The write-up from the other website says just the opposite. Also, the other write-up says I should expect to see 5Vdc on the Temperature Diagnostic Switch when it is open. I get full battery voltage there and the FSM EGR section's minimal schematic indicates 12 Vdc is correct.
I bent the tip of a small rod to use to feel the diaphragm of the EGR valve to know whether it is opening. I can also use it like a prybar to manually force it open.
Yesterday, I manually forced the valve open while monitoring the Temperature Diagnostic Switch wire with my voltmeter and didn't see it change. That certainly makes the switch suspect.
Today, I verified the operation of the EGR solenoid to be as the FSM EGR section says in that pulling the wiring harness plug from the solenoid, thus de-energizing it and revving the engine, I could feel the EGR valve opening. When I plugged the harness back in and ran the same test, I couldn't feel any movement of the EGR valve diaphragm. This seems to imply that the solenoid is energized as it should be to prevent any EGR action while idling, in park, or neutral.
This brings me to the reason for this post: A voltage measurement on the pink/black wire to the solenoid showed only 2.4 Vdc. I was expecting to see full battery voltage. Thinking that I might have a high resistance open, I raked that lead quickly across a ground point and was surprised to see a much more substantial arc than I would expect from a 2.5 volt source. After that, I am now measuring less than 2 volts. To test for a high resistance open in that wire, I unplugged the harness from the solenoid so that the solenoid coil couldn't supply a load to cause a voltage drop and still I measure less that 2 volts. Has anyone tested voltage on their pink/black wire at the solenoid and if so, what voltage was measured? Less than 2 volts doesn't sound right to me although my first test seems to show the solenoid is being energized by that low of a voltage.

 

And the third is a vacuum leak.

How's it idle when warm?

 

After the FIC injector install the engine runs like new smooth and has a very smooth idle.
I was hoping to get verification of the voltage to expect at the pink/black wire in the EGR solenoid harness. Further, I was hoping for a comment as to why the two documents I referenced are so at odds with each other.

 

Check your "GAGES" fuse and test it again. It should be B+ voltage.
Your other tests point straight at the EGR diag. switch. They are
easy to break when you are in there working nearby. Very easy.
Benny

 

Did you happen to pull the runners off while swapping the injectors?

Are you sure the correct gaskets were placed in the correct position?

Just a thought.

 

You nailed it! The Gages fuse was blown. Replaced it and have full battery voltage at the pink/black wire. Now I'm second guessing myself. I think I blew that fuse when I struck the wire to ground judging from the arc it drew. Now, I must have either misread the meter's display as in I didn't see the 1 preceding the 2.25, or the meter for some reason failed to light the segment, making it look like it was reading 2 volts instead of 12.
Since the diagnostic switch is a $10 part, I will replace it and see what happens next time out on the freeway.
Thanks everyone for the replies.

 

I had a similar problem on my 87. When I would drive home in the afternoon from work (26 miles mainly freeway) I would get a code 32. Driving around town and also cooler morning temperatures driving to work never set a code. While I was working on changing the manifold gaskets I bought an EGR from AutoZone and now I don’t have any more codes. I noticed the old one was really full of carbon where the EGR flange and manifold flange met.

 

Not sure if this helps, but I was having the same symptoms...only set an Code 32 when driving on the highway after about 15 minutes. Followed the diagnostic in the Shop Manual and figured if I was going to take the plenum off to get to the EGR valve, I better have a new valve on hand. When I got to the EGR valve itself, it seemed to be holding a vacuum okay but the little sensor that screws into the base of the EGR valve was loose. I ended up replacing the EGR valve which came with a new sensor and this stopped the code from happening. I've always wondered if the solution was all in the loose sensor and not the EGR valve itself, but since the EGR itself was not that costly and I didn't want to have to go back in there a second time, I'm okay with having changed a part that might not have been defective. If you find the sensor on the base of the EGR is loose, or not grounding that might be the problem and not the EGR valve itself.

 

Any progress on the conflicting documents?

 

No, but i have finally figured out the forum member's nick whose site at http://www.geocities.com/jgkov contains the document. It is 65Z01.

 

Pulled the EGR Temperature Diagnostic switch out today to check its operation. I found the porcelain on the switch was not broken, but rather the piece that the wire is crimped to that screws into the porcelain is loose and free to turn. It appears that how far it is screwed in sets its trip point when heated.
Went online to get the part numbers for a couple makes for the '86 at the NAPA website. Took those numbers to the local NAPA store to try to purchase a replacement. No go. Don't have it and their warehouse doesn't either. OK then, I'll just do an online order from Autozone. They're 50% cheaper anyway. Got to checkout and they don't have it in stock. Tried Schucks and they don't even list one. So the heck with it, then! I'll just see if I can repair the thing myself. I removed the switch, clamped it in a vise, put my ohmmeter leads across it, turned the piece that has the wire crimped to it in until contact was made, backed it off until contact was broken, heated it with a torch to see if it would make contact to ground and it did, let it cool down to see if it would open back up and it did. I put super glue on the threads to hold that adjustment and put it back on the vehicle. I started the engine and forced open the EGR valve while observing the voltage on the switch lead. After a bit, the switch closed and the voltage went to zero.
I won't know for sure if this will work until I can take it on a freeway run. If it doesn't, I am going to do a mod to fake the computer into believing the switch has closed as in 65Z01's document although that will require using a relay with its coil across the EGR solenoid harness and its NC contacts connected in place of the diagnostic switch terminals.
Finally got out on the road today and got the code again. Apparently the switch repair didn't work.

 

I have noticed I'm in need of the same part. I think I have found it @ ECKLERS part number 35050 for 85's and 35029 for 86-89. Its like $13 there...Just a heads up..

 

Ask them for the camaro switch. The wire is a few inches longer but
I have found it to be available when the corvette part isn't. Its about
the same cost. Or there is eckler's. Benny