EGR Temperature Switch???
Thread Starter
Racer
Joined: Mar 2004
Posts: 305
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From: Houston Texas
EGR Temperature Switch???
Can anyone tell me where the EGR Temperature Switch is located on my '85 vette coupe?
I purchased a new one, thinking that if I saw what it looked like, I could find the old one. I don't have a clue. The switch screws into the engine. and has a wire plug at the end. My repair manual talks about the switch, but not about where it is at. :confused:
I purchased a new one, thinking that if I saw what it looked like, I could find the old one. I don't have a clue. The switch screws into the engine. and has a wire plug at the end. My repair manual talks about the switch, but not about where it is at. :confused:
Team Owner
Joined: Dec 2000
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From: SE NY
Cruise-In II Veteran
Re: EGR Temperature Switch??? (1slyder1)
Look on the front of your EGR valve under the plenum; the temp sensor should screw into the base of the valve just above the front bolt.
On later systems the sensor was in the EGR tube between the right exhaust manifold and the intake base.
On later systems the sensor was in the EGR tube between the right exhaust manifold and the intake base.
Team Owner
Joined: Dec 2000
Posts: 90,675
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From: SE NY
Cruise-In II Veteran
Re: EGR Temperature Switch??? (1slyder1)
If yours is indeed under the plenum then yes you will need to remove the plenum.
But that isn't such a big job; it's removing the runners where it gets to be a little more fun.
But that isn't such a big job; it's removing the runners where it gets to be a little more fun.
Team Owner
Joined: May 2002
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Re: EGR Temperature Switch??? (65Z01)
What led you to replace the temp switch? Did you follow the diagnostic procedure through the GM manual?
You can test the EGR temp switch off of the car by hooking up a voltmeter between the wire lead and the metal body of the temp switch.
Now, set your meter to check for continuity, and hold a lighter under the end of the temp switch. It should show continuity within 20 seconds or so when it heats up.
You can test the EGR temp switch off of the car by hooking up a voltmeter between the wire lead and the metal body of the temp switch.
Now, set your meter to check for continuity, and hold a lighter under the end of the temp switch. It should show continuity within 20 seconds or so when it heats up.
Burning Brakes
Joined: Apr 2004
Posts: 762
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From: Huntington ma
Re: EGR Temperature Switch??? (1slyder1)
code 32 doesn't necessarily (or even usually) mean the temp switch is Bad - it means it's ON. Why becomes the question - is the EGR valve itself stuck? Is it being left open by a faulty control solenoid (most likely cause in my experience - those control solenoids seem to me the weak link in the system). The Helms (GM) manual has a pretty good diagnostic procedure for sorting out this issue..... Don't condem the temp switch! It's usually the messenger, not the message... :nono:
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Team Owner
Joined: May 2002
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Re: EGR Temperature Switch??? (1slyder1)
I had a bad temp switch, and there was no code 32. I actually tried disconnecting it.. and running the car, and it still didn't set even when the EGR opened.
You can diagnose the egr solenoid by grounding the ALDL diagnostic ports, and there's something else... I'll check the manual. You'll also need a hand vacuum pump to see if its' actually opening and closing allowing vacuum to the egr at correct times.
[Modified by CentralCoaster, 5:18 PM 5/19/2004]
You can diagnose the egr solenoid by grounding the ALDL diagnostic ports, and there's something else... I'll check the manual. You'll also need a hand vacuum pump to see if its' actually opening and closing allowing vacuum to the egr at correct times.
[Modified by CentralCoaster, 5:18 PM 5/19/2004]
Team Owner
Joined: Dec 2000
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From: SE NY
Cruise-In II Veteran
Re: EGR Temperature Switch??? (CentralCoaster)
There is an EGR diagnostic method on my site that uses engine vacuum instead of a hand vacuum pump.
Indeed if you disconnect the temp switch the ECM "may" not set a code; it only calls for EGR during cruise if coolant temp is greater than 175deg F.
Indeed if you disconnect the temp switch the ECM "may" not set a code; it only calls for EGR during cruise if coolant temp is greater than 175deg F.
Thread Starter
Racer
Joined: Mar 2004
Posts: 305
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From: Houston Texas
Re: EGR Temperature Switch??? (rons85)
I'd rather replace the solenoid than the temp switch any day. At least the solenoid isn't buried under the plenum.
I've had this car for about 16 months, and have no idea how good (or bad) the previous owner took care of it. The way I figure it, it's an '85, and if I keep on replacing sensors, relays, etc., she'll eventually be a new car. (I have already rebuilt the tranny and replaced several relays.)
I appreciate all of y'alls help. I can always count on the corvette forum to steer me right. :thumbs:
[Modified by 1slyder1, 6:02 PM 5/20/2004]
I've had this car for about 16 months, and have no idea how good (or bad) the previous owner took care of it. The way I figure it, it's an '85, and if I keep on replacing sensors, relays, etc., she'll eventually be a new car. (I have already rebuilt the tranny and replaced several relays.)
I appreciate all of y'alls help. I can always count on the corvette forum to steer me right. :thumbs:
[Modified by 1slyder1, 6:02 PM 5/20/2004]
Team Owner
Joined: Dec 2000
Posts: 90,675
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From: SE NY
Cruise-In II Veteran
Re: EGR Temperature Switch??? (1slyder1)
Normal running temp is 200+deg F but I run a 160 deg T-stat & fan switch so my coolant temps normally run 155-165deg F. Only when air temps climb into the 90s does my coolant temp get into the 170deg range.
Team Owner
Joined: May 2002
Posts: 24,337
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Re: EGR Temperature Switch??? (1slyder1)
The way I figure it, it's an '85, and if I keep on replacing sensors, relays, etc., she'll eventually be a new car.
Now I'm starting to believe that those small expenses are just there to warm me up to the idea of dumping hundreds of dollars into it every month without hesitation.
Thread Starter
Racer
Joined: Mar 2004
Posts: 305
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From: Houston Texas
Re: EGR Temperature Switch??? (CentralCoaster)
Well, I replaced the solenoid switch last night. Reset the engine codes. So far, so good. No code 32. Now, all I have left, is to replace the knock sensor. I am not complaining. I'm just glad these are things that I can do myself. :D
