Service Engine Soon help
Thread Starter
Burning Brakes
Joined: Feb 1999
Posts: 1,157
Likes: 3
From: Encino CA
Service Engine Soon help
My 95 LT-1 has actually been driving pretty good and my gas mileage has also been better than normal of late. However, I was driving home today at about 35-40 mph when the Service Engine Soon light suddenly came on. I have never gotten this light before. I used the paper clip method to pull codes and got the C12 (which I believe is a good thing). When the display was cycling through the various modules I got an H32 at module 4 (specifically module 4.1). I believe this might be a history code having to do with EGR?
That was the only code that showed up. How do I address? Is it basically the EGR valve that needs replacing?
Thanks,
Doug
That was the only code that showed up. How do I address? Is it basically the EGR valve that needs replacing?
Thanks,
Doug
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 207
From: Orlando FL
There is an EGR solenoid which is electrically operated and controls the vacuum to the actual EGR valve. The PCM monitors the solenoid directly which could be the problem.
The EGR valve which is solely vacuum operated has no electrical connection. However the way it works and effects the exhaust can show up indirectly in other codes like O2 which monitors the mixture. I wish I was more up on this specific situation since I only read about it in the past which was not completely informative. In that case an indirect indication could point to the EGR valve.
Use this information as a guide to figure out what’s going on. I would clear the codes and see if it re-occurs again. However it seems to be an electrical fault but cannot look at book now to confirm what is monitored to trigger code 32.
The EGR valve which is solely vacuum operated has no electrical connection. However the way it works and effects the exhaust can show up indirectly in other codes like O2 which monitors the mixture. I wish I was more up on this specific situation since I only read about it in the past which was not completely informative. In that case an indirect indication could point to the EGR valve.
Use this information as a guide to figure out what’s going on. I would clear the codes and see if it re-occurs again. However it seems to be an electrical fault but cannot look at book now to confirm what is monitored to trigger code 32.
Team Owner
Joined: Oct 2000
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From: Fort Knox, KY
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Check you EGR valve. It could be clogged with carbon and/or the diaphragm on it might be cracked from age/engine heat, allowing it to lose vacuum. That's what happened to mine.
I replaced the valve, cleared the codes, viola! No more Code 32 for me!
I replaced the valve, cleared the codes, viola! No more Code 32 for me!
Thread Starter
Burning Brakes
Joined: Feb 1999
Posts: 1,157
Likes: 3
From: Encino CA
Before starting today, I glanced at the connections to the solenoid, checked the vacuum lines and connections running to the EGR, and also manually pushed the diaphragm by sticking my finger in the slotted cover of the EGR. I then started the car and there was NO Service Engine Soon light (I assume this goes off automatically and resets when the ignition is turned off), and the car drove fine with no apparent problems. I wonder if the code 32 was triggered by my new style of driving to get better mpg. Basically, I drive like there is an egg between my foot and the pedal and when up to speed, back off pretty quickly and essentially coast. When the light came on yesterday, the auto was in overdrive and I was coasting down to about 30-35 upon going through an intersection. Maybe it was the weak vacuum under those conditions that did not properly suck the EGR diaphragm because that is precisely when the light came on--just guessing.
What a crummy way to drive a Vette
. However my mpg has gone from about 14-15 to more like 16-17 for my 6 miles to work and 6 miles back home daily drive.
Doug
What a crummy way to drive a Vette
. However my mpg has gone from about 14-15 to more like 16-17 for my 6 miles to work and 6 miles back home daily drive. Doug
