Diesel Place banner

1 - 19 of 19 Posts

·
Registered
Joined
·
73 Posts
Discussion Starter #1
hey i have a 96 k1500 i need some info on the egr system on the truck what im wondering is if i delete the egr ex: drop a frost plug in the upper intake! how do i cheat the comp from goin into limp mod? and is there a better method cuz i have a bad miss around 1500 rpm and tarable fuel millage!:confused:
 

·
Registered
Joined
·
3,142 Posts
You cant cheat the PCM (computer). You have to get it reflashed to delete the EGR.
Your PCM should not go into limp mode if the EGR is not working. It will usually just light the SES light. You may have other problems besides the EGR. Check for trouble codes.
 

·
Super Moderator A Country Boy Can Survive...
Joined
·
14,350 Posts
There is one way to cheat the computer. This works on OBD I(94-95) trucks. I'm not sure if it'll work on 96+ OBD II but it can't hurt to try.

Follow the vacuum line that goes from the EGR to the solenoid bank. That line should split to a sensor that's mounted on the firewall.

Block off the vacuum connection at the EGR valve and you shouldn't get a SES light.

That sensor that's on the firewall is the "feedback" sensor more or less. It checks for vacuum at the sensor when the ECM commands the solenoid to "turn on" the EGR. If it doesn't see vacuum it throws a code.

However if the vacuum is still present at the sensor when the ECM commands the EGR to "turn on" then the ECM thinks everything is fine(even though the line is plugged at the EGR), so you don't get a SES light.
 

·
Registered
Joined
·
73 Posts
Discussion Starter #4
well i had that boost issue that the turbo master fixed but still have that stumble and poor fuel millage so i kno the egr has always had a problem i kno the white sillanode is shot! but i want to delete the egr all together want a f upper intake for it when i get some money but ill try it this way frist thanks guys!
 

·
Registered
Joined
·
73 Posts
Discussion Starter #5
so i unpluged the egr a blocked the vac line and yet it still has the stumble im not sure what it could be maybe an intake leak?
 

·
She Don't Smoke!
Joined
·
4,690 Posts
Usually a bad EGR is indicated by a rough idle or rough acceleration, not really many problems heard while cruising. You can try throwing in a frost plug in the lower intake to see if that helps or not, the EGR may not be sealing properly but like I said usually a bad egr causes rough idle and etc....

Intake leak shouldn't cause studdering or anything, you'd hear air and see it if your intake is clean. Diesel's aren't like gassers, since Diesels are fuel regulated while gas engines are air regulated.

Usually studdering is caused by something with the fuel system, but EGR can also cause under certain circumstances.
 

·
Registered
Joined
·
7,411 Posts
Is the mystery gasket under the egr? Best change manifolds... Second best is to install HD intake gasket with the built in EGR port blocked.
 

·
Registered
Joined
·
73 Posts
Discussion Starter #9
i had the upper intake off a few weeks ago to drill an tap it for my bost guage dont remeber seeing that gasket but ill pull i back off a check! thanks guys ill keep it posted! and what about manafolds?
 

·
Registered
1995 GMC Suburban
Joined
·
17,827 Posts
Also check the lines that connect everything.
 

·
Registered
Joined
·
73 Posts
Discussion Starter #12
but i pulled the vac line off the egr an pluged it so would that not elimate a vac problem?
 

·
Registered
1995 GMC Suburban
Joined
·
17,827 Posts
I suspect that you still vacuum to your solenoids?
 

·
Registered
Joined
·
73 Posts
Discussion Starter #14
Is the mystery gasket under the egr? Best change manifolds... Second best is to install HD intake gasket with the built in EGR port blocked.
this gasket is not there i just took the upper intake off and checked
 

·
Registered
Joined
·
73 Posts
Discussion Starter #15
and yes i still have vac to the the silanods
 

·
Registered
Joined
·
23 Posts
EGR Dummy

If you dont want to re-flash, this is working, maybe even on -97.
I try it on my OBH1 -95 and it's working good, no SES.
Cut the cabels to both valve and MAP and conect the dummy.
 

Attachments

·
Registered
Joined
·
73 Posts
Discussion Starter #19
now on a 96 s vin is there gasket spost to be there? and what is it called
 
1 - 19 of 19 Posts
Top