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Discussion Starter · #1 ·
I tried searching for someone who capped off their EGR. Does anything need to be done with the ECU because now there's a dead plug hanging there?
When I put the replacement junkyard engine in (b21 for a b21) I'm getting a really bad idle and I wanted to check the timing but the RPM's won't stay steady below 2k enough to get the timing light on it. I'm going to try the adjustments found and tricks for the irractic idle on the board tonight when I get home but I was wondering if it could be something else.
Only thing I did differently before putting the engine in is remove the egr and by-passed the tb/intake coolant lines. No leaks on any of the vacuum hoses, checked with carb spray.
Does the Ecu have to be refreshed even though the battery was out for a week?
 

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i highly doubt the EGR system causing your high (surging?) idle...search for threads there are TONS that show possible idle problems.
and about the ECU you cannot 'refresh" it in any other way besides disconnecting its power source for 10seconds(resets it) i think it is if it was out without a battery for a week its as "refreshed" as u can get.
 

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no mo mod
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if EGR was stuck open, it would cause a low idle...unless you dont have the EGR tube there and your leaking past both the valve and where the tube connected to the intake mani.
what I did was just cut the end off the old EGR tube off, had a guy weld up the hole, replaced that gasket and the EGR valve gasket and put everything back where it was. this way, I dont have EGR, but the ECU still thinks there is :) no MIL!
 

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Discussion Starter · #4 ·
What I did was welded a bolt into the nut on the on the the exhaust manifold. And I cleaned up the gaskets and RTv'd the crap out of them, fabricated plates in the same shape as the 2 openings on the intake and sealed it shut. I can spray carb cleaner all around the intake no surge in idle @ all so I know all of that is sealed shut nice and tight.
But do you necessarily need to have the connector plugged in or could this becausing my surges? Will not having the egr plugged in throw a code and the ECU will mess with fuel/air mixture?
 

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you need the egr still plugged in. mount it to the firewall or something. if you just unplug the egr valve, you will get a code and usually a CEL, and it will affect your idel greatly.

so yes, i would say that is the entire cause of your problem. bolt the egr valve somewhere, anywhere, and plug the harness back into it. extend the plug's wires if you need to. then reset the ecu, and try again.

keep in mind though, with everything blocked off, the car will still run a little funny no matter what until it warms up. once it warms up it should run fine, but until fully warmed up it will still idle a little strange and may even drive slightly wierd, again, til its warmed up fully.
 

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Memento Mori
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Actually throwing an EGR code does nothing, except light up your check engine light, there wont be any difference in idle or how it runs with or without the EGR. 3g ludes arent like some newer cars that run like shit if there is something wrong with the EGR, I feel like Honda just kinda throws it on there after the fact so they can sell cars here. :)
 
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