E.G.R. Question(s)
Thread Starter
Heel & Toe
Joined: Jun 2017
Posts: 17
Likes: 0
Actually I would like to do that. How do I go about having the ECU reprogrammed? Also Are there any issues or problems that may come from doing this?
Team Owner
Joined: Jul 2004
Posts: 28,502
Likes: 3,302
From: Hartford WI
Thanks Much I will do that!
Got the fuel pump back in today and the car started right up.Runs okay but still does not want to idle when it`s warmed up. I also notice that it seems to be "loading up" I think that yes the next step would be to test out the injectors and that EGR.
Got the fuel pump back in today and the car started right up.Runs okay but still does not want to idle when it`s warmed up. I also notice that it seems to be "loading up" I think that yes the next step would be to test out the injectors and that EGR.
Team Owner
Joined: Jul 2004
Posts: 28,502
Likes: 3,302
From: Hartford WI
You can, if you are not going too far with your mods, pay someone to "guess a tune" and remove the EGR code. Issues are you will void your warranty with GM
Instructor
Joined: Feb 2016
Posts: 130
Likes: 17
It's very easy to disable the EGR in your bin which is in the chip if you have the right equipment and tuning software, so it's not like you are asking a lot if you know someone who can do it.
Racer
Joined: Jun 2017
Posts: 311
Likes: 24
From: Ohio
From what I have read when retuning ECM for EGR delete all one would due is raise the EGR activation temp to a point where the engine would never reach. There are some systems that are simply on/off but I don't think the ERG is one of them. So I don't think there would be much "guessing a tune". But I still don't think the EGR is your problem. I would try to fix the problem before moving on to mods or deletes. It may compound the problem leaving you more frustrated and discouraged to work on your car. I have tried to follow this post but I'm not sure if you have mentioned exactly how it runs when its just idling. Does it surge and then die? Or does it just simply idle down/running rough then die?
Racer
Joined: Jun 2017
Posts: 311
Likes: 24
From: Ohio
It would be best to find someone in your area, maybe part of a GM OBD1 type car club, and see if anyone has a programming tool that will work with a 85 chip and just offer to pay them a little. The 86+ have different ECUs and chips. For example, I modified my 85 ECU to use 86+ chips because that's what most tools for that era are compatible with. I can't write the 85 chips.
It's very easy to disable the EGR in your bin which is in the chip if you have the right equipment and tuning software, so it's not like you are asking a lot if you know someone who can do it.
It's very easy to disable the EGR in your bin which is in the chip if you have the right equipment and tuning software, so it's not like you are asking a lot if you know someone who can do it.
Thread Starter
Heel & Toe
Joined: Jun 2017
Posts: 17
Likes: 0
Well it idles fine until it starts warming up. The closer to around 180-200 degrees it gets the worse it idles. It will surge and stall.
So far I cleaned the throttle body,Put in a new Idle control valve,New TPS,new plugs,cap and rotor,, New fuel filter and pump,also a new pvc valve. I got a new coolant temp sensor but haven't put it in yet.
So far I cleaned the throttle body,Put in a new Idle control valve,New TPS,new plugs,cap and rotor,, New fuel filter and pump,also a new pvc valve. I got a new coolant temp sensor but haven't put it in yet.
Racer
Joined: Jun 2017
Posts: 311
Likes: 24
From: Ohio
Thank you, it might not be a bad idea to swap the injectors bc I'm sure they have some crud in them but I don't think they are the problem. If they were the problem the issue would occur at all times. Bc the problem only occurs while the engine is warm I going to say that it is a sensor problem. It wouldn't be a bad idea to swap out the temp sensor but I'm not sure it is your problem. Correct me if I'm wrong anyone but it sounds like once it warms up and swaps into open loop it senses something is wrong and the computer is trying to swap between open and closed loop. During closed loop the car runs off what is programmed into the ECM, during open loop it runs off sensors and that is where your problem occurs. I may be wrong but as far as I know this is the basics of how it operates. Honestly it sounds like my car does the exact same thing as yours but less often. Sometimes when I pull up to a stop sign in my 84 it will surge going from higher rpm to lower rpm but mine doesn't die. Sorry for the long reply
Last edited by MikeP84; Jul 3, 2017 at 01:34 PM.
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Team Owner
Joined: Jul 2004
Posts: 28,502
Likes: 3,302
From: Hartford WI
Thank you, it might not be a bad idea to swap the injectors bc I'm sure they have some crud in them but I don't think they are the problem. If they were the problem the issue would occur at all times. Bc the problem only occurs while the engine is warm I going to say that it is a sensor problem. It wouldn't be a bad idea to swap out the temp sensor but I'm not sure it is your problem. Correct me if I'm wrong anyone but it sounds like once it warms up and swaps into open loop it senses something is wrong and the computer is trying to swap between open and closed loop. During closed loop the car runs off what is programmed into the ECM, during open loop it runs off sensors and that is where your problem occurs. I may be wrong but as far as I know this is the basics of how it operates. Honestly it sounds like my car does the exact same thing as yours but less often. Sometimes when I pull up to a stop sign in my 84 it will surge going from higher rpm to lower rpm but mine doesn't die. Sorry for the long reply
Racer
Joined: Jun 2017
Posts: 311
Likes: 24
From: Ohio
Haha you are correct, I always swap the two. For some reason when I think about open loop I think open to sensor input and closed to input.
Thread Starter
Heel & Toe
Joined: Jun 2017
Posts: 17
Likes: 0
Been off the forum for a while but on the plus side I got the Car running pretty good.After cleaning the fuel tank out and putting a new fuel pump and filter in I decided to check the timing, ( something you really should t half to do on this car) Well it was way off. Got that dialed in and replaced a few vacuum lines. Took it out for a spin and all seems well even idles good.
So now I started trying to straighten out some of the wiring issues.One dumb question... Should my Security light be flashing all the time? (when the engine is not running). If not what might be going on here?
So now I started trying to straighten out some of the wiring issues.One dumb question... Should my Security light be flashing all the time? (when the engine is not running). If not what might be going on here?
Supporting Vendor
Joined: Oct 2004
Posts: 761
Likes: 68
Hello there,
I am going to put my 2 cents in here.
The EGR is not a bad thing to have on your car. When mine failed it made a huge mess because I did not know it at the time. I was at the emissions station and then I learned my NOX was so high that my car could not get approval.
I came home and tore into it. My EGR was replaced after much work to the entire intake manifold system. In the process of fixing my car I ended up rebuilding my fuel pressure regulator and finally found the reason my EGR failed in the first place. The little solenoid that attaches at the thermostat housing had failed. The Vacuum lines were very brittle as well. So after installing a new throttle body, EGR, the EGR Solenoid and the Cold Start Valve I had learned a lot. I also changed all the old vacuum hoses and now even my Cruise Control works great.
I live in Northern Virginia and a car's emissions have to be tested every two years until the car is 25 years old. My car does not need to be tested but I still go through the process anyway. I like to know if my emissions systems are working, I want them to work properly. For $18 I get a pretty good checkup on my car and its engine's emissions system.
There are a lot of people that like removing things they consider detrimental to all-out performance. I am not one of them. I will keep my car running with the systems it was designed with. My emissions are now within the bounds of the laws here and my car runs strong and CLEAN.
I wish you the very best in getting your Corvette fixed right.
I am going to put my 2 cents in here.
The EGR is not a bad thing to have on your car. When mine failed it made a huge mess because I did not know it at the time. I was at the emissions station and then I learned my NOX was so high that my car could not get approval.
I came home and tore into it. My EGR was replaced after much work to the entire intake manifold system. In the process of fixing my car I ended up rebuilding my fuel pressure regulator and finally found the reason my EGR failed in the first place. The little solenoid that attaches at the thermostat housing had failed. The Vacuum lines were very brittle as well. So after installing a new throttle body, EGR, the EGR Solenoid and the Cold Start Valve I had learned a lot. I also changed all the old vacuum hoses and now even my Cruise Control works great.
I live in Northern Virginia and a car's emissions have to be tested every two years until the car is 25 years old. My car does not need to be tested but I still go through the process anyway. I like to know if my emissions systems are working, I want them to work properly. For $18 I get a pretty good checkup on my car and its engine's emissions system.
There are a lot of people that like removing things they consider detrimental to all-out performance. I am not one of them. I will keep my car running with the systems it was designed with. My emissions are now within the bounds of the laws here and my car runs strong and CLEAN.
I wish you the very best in getting your Corvette fixed right.
Drifting
Joined: Mar 2017
Posts: 1,897
Likes: 165
From: Nashville TN
2017 C4 of Year Finalist
Been off the forum for a while but on the plus side I got the Car running pretty good.After cleaning the fuel tank out and putting a new fuel pump and filter in I decided to check the timing, ( something you really should t half to do on this car) Well it was way off. Got that dialed in and replaced a few vacuum lines. Took it out for a spin and all seems well even idles good.
So now I started trying to straighten out some of the wiring issues.One dumb question... Should my Security light be flashing all the time? (when the engine is not running). If not what might be going on here?
So now I started trying to straighten out some of the wiring issues.One dumb question... Should my Security light be flashing all the time? (when the engine is not running). If not what might be going on here?