Rough idle, after LT install and EGR delete

[BlackArtemis]

I tried attaching this to the other similar thread, but got no bites

Installed BBK headers and catted H
Removed EGR and DPFE
used the Lethal Performance EGR block plate and header cap.
Deleted 1 red vacuum line and the green one.
Now the red vacuum goes from passenger side to plenum to fuel
Checked PCV, bearing moves w/o problem
But the PCV valve hose was collapsing. I replaced it with some heater hose from ACE and tightened it with a clamp.
Told Bama tuners I removed EGR and to account for that in my tune (no more check engine light)


But I still get a drop in RPMs from 1100 to 500. When it idle it gently goes up and down. After a rev it comes down smoothly, hits 1100 and does a sharp drop, sometimes it sounds like it will stall out.

What else can I check?
Clean MAF?
O2's were brand new and have under 500miles on them
Smoke test (how could I do this?)

thanks all

 

[tangtang]

ok i had to take in to account that when installed my LT BBK's i had to raise an drop the motor to get them to go into place. when doing this i pulled a vacuum line off the backside of my throttle body rite under the throttle cable where it meets the throttle body. i would check all your lines to make sure they are connected an look for any place that looks like it needs a hose connected but there isnt one. thats most likely your problem. i had the exact same symptoms. the smoke check....well i jus lit a cigarette an blew the smoke on the exhaust. if there is a leak (epecially with the way your changing RPM's) you will see the leak push the smoke away. good luck

 

[BlackArtemis]

yeah, I read your problem, I saw a hose maybe a little less in diameter than a sharpie right in the back, ran out hoping it wasn't in, it was. I will check there again though

 

[tangtang]

yeah, I read your problem, I saw a hose maybe a little less in diameter than a sharpie right in the back, ran out hoping it wasn't in, it was. I will check there again though

jus make sure you check both ends. its a vacuum line...but not the only vacuum line either.

 

[BlackArtemis]

You know, I didn't even think about checking the other end. Don't think any lines are cracked either. This is what I got. Ignore the dirt it has sat for almost a year ( last winter, months of travel and no inspection haha).

I'm hoping I just did something stupid and it's a simple "You didn't plug in X to Y, idiot!"