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Judging by its condition yes someone had messed with it before. To make it worse my dad started screwing with it yesterday after I told him NOT to screw with it. Not the first time he hasn't listened to me when it comes to vehicle 🤬. Last time he didn't listen he about lost a wheel going down the road after I told him that the CV axles on his 98 Chevy help hold the bearings together……
I rebuilt my first motor with my dad (he built engines) and had to rebuild it for the opposite reason you have! I was doing the driver side head install while he was showing me on the passenger side. He showed me how to torque the heads bolts and read the beam. He then climbed out to smoke. He never torqued hood side down past the first pass, said he figured I would finish!
Get truck nice and warm, unplug IAC and assist screw so it barely runs (550 rpm). Shut truck off, plug back in and disconnect neg battery cable for 30 minutes to reset computer.
I rebuilt my first motor with my dad (he built engines) and had to rebuild it for the opposite reason you have! I was doing the driver side head install while he was showing me on the passenger side. He showed me how to torque the heads bolts and read the beam. He then climbed out to smoke. He never torqued hood side down past the first pass, said he figured I would finish!
Get truck nice and warm, unplug IAC and assist screw so it barely runs (550 rpm). Shut truck off, plug back in and disconnect neg battery cable for 30 minutes to reset computer.
So I used some aluminum from a knife tin to block the EGR off and ran it hard for a few miles to get her warm. Drove like a dream, so what does that indicate? I don’t know much about EGR systems on gassers
Either the EGR is intermittently sticking open (even if just a small amount is unaccounted for air) or something, computer command or evr keeping small amount of vacuum, is telling it to not fully close. You can preliminary test this by removing the plug and running the truck. When it does it again, pull the vacuum line to see if it immediately goes back to normal rpm. If it don’t, EGR is sticking. If it does, then something is telling it to stay open.
Other option, depending on how much you care about it. Leave the piece there and never deal with it again!
Last edited by 90project5.0; Apr 26, 2026 at 11:38 AM.
Either the EGR is intermittently sticking open (even if just a small amount is unaccounted for air) or something, computer command or evr keeping small amount of vacuum, is telling it to not fully close. You can preliminary test this by removing the plug and running the truck. When it does it again, pull the vacuum line to see if it immediately goes back to normal rpm. If it don’t, EGR is sticking. If it does, then something is telling it to stay open.
Other option, depending on how much you care about it. Leave the piece there and never deal with it again!
I am about to leave it in the thing lol. Unplugging the electrical end doesn’t make a difference on how it runs, (checked the voltage at the plug and it was 5v which from what Ive read is correct) same with the vacuum line so that tells me it is sticking (unless I misread what you said). Also would adding the gasket affect running with the block off plate? I ask this because when I pulled the valve off the first time to add that plate there was no gasket. I bought one and added it to the plate and it went on the fritz again haven’t added the plate back yet because my dad was trying to convince me that it’s something else lol
Last edited by AvtomatKentucky101; Apr 27, 2026 at 08:55 PM.
I am about to leave it in the thing lol. Unplugging the electrical end doesn’t make a difference on how it runs, (checked the voltage at the plug and it was 5v which from what Ive read is correct) same with the vacuum line so that tells me it is sticking (unless I misread what you said). Also would adding the gasket affect running with the block off plate? I ask this because when I pulled the valve off the first time to add that plate there was no gasket. I bought one and added it to the plate and it went on the fritz again haven’t added the plate back yet because my dad was trying to convince me that it’s something else lol
Not having a gasket could have definitely caused the problem in the first place! Nothing to take out the gaps with thermal expansion.
5v is the correct voltage. Making sure I understand what you’re saying. EGR,plate, intake gives no problems (stops issue). EGR, gasket, plate, intake gives problems?
Not having a gasket could have definitely caused the problem in the first place! Nothing to take out the gaps with thermal expansion.
5v is the correct voltage. Making sure I understand what you’re saying. EGR,plate, intake gives no problems (stops issue). EGR, gasket, plate, intake gives problems?
I figured it should have one, but yep when I add one it gives me issues
As far as I know the gasket doesn’t effect the old egr valve, probably because it doesn’t work anyway. But as for the plate yeah its bigger than the hole. I am going to try it again this evening after work without the gasket and see if it fixes it again lol
Last edited by AvtomatKentucky101; Apr 28, 2026 at 07:15 AM.
As far as I know the gasket doesn’t affect the old egr valve, probably because it doesn’t work anyway. But as for the plate yeah it’s bigger than the hole. I am going to try it again this evening after work without the gasket and see if it fixes it again lol
Blocked it off again with a new plate made to the exact specs as the old one. It’s runs good! And since I don’t care about emissions it’s staying blocked off. Thanks fir the help, hopefully I won’t have to but if anything changes I will give a update here. Thanks again!
I ran mine the same way for about 1 yr before I said screw it and completely removed it and the tube. Hopefully nothing new comes up!
The problem with that is the ECM/ PCM is looking for a closed voltage and then a different voltage when the EGR is command open. There are probably codes in the computer even though the light is not on.