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EGR receiving vacuum at low rpm's and on acceleration

(1990 Pontiac Sunbird)
in Seattle, WA on June 15, 2014
did the egr test (snapped throttle and check if valve is open on deceleration)-chiltons) my EGR is open on acceleration and closes on deceleration? this is causing my car to idle rough and run rough under 2Krpm (anything below heavy acceleration)
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Popular Answer
on June 15, 2014
Simply unhook EGR valve.... idle ok then??..... Maybe that aint your problem!
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on June 15, 2014
im not sure what you mean? if i unhook/bypass the egr yes it does idle/run better, true. I guess what I'm wondering is, with the egr system hooked up (i believe i need this system for emissions tests I'm about to do?) it does not idle or run very good at low rpm's, because the egr seems to be opening at low rpm and acceleration (which according to chiltons it shouldn't be doing?). so I think i was wondering what cold be causing the egr to open at low acceleration/rpm, when it does indeed run better without it opening, so i would also think it shouldn't be opening.

Or, this is correct function of egr/egr-system and it is something else? what should I check?

Thank you!

(ALSO: according to the egr valve it is positive pressure:P )
on June 15, 2014
I mean pull vacuum hose off the valve!.... Got any trouble codes?? Check engine light on??
on June 15, 2014
You answered your own question, the EGR is NOT supposed to be open at idle. Verify cause , could be incorrect signal(control -NOT valve).
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on June 15, 2014
Kinda like a solenoid thing....
on June 15, 2014
Ok no i misspoke I'm sorry (it is NOT open at idle). But It does open, and effects smoothness at low rpm (under 2K rpm) unless under a load.

so it seems to be closed at idle, but as soon as i give even a little gas it opens (seems to fully open) which causes the car to jump and sputter. If i give it MORE than quarter throttle, or am accelerating even lightly while driving it doesn't jump and sputter. (it only seems to have effect if i take off lightly or am barely touching gas cruising, at this point it seems its jumping and running bad because the egr is open when it should not be) (small/weak spring in egr bad?)

No trouble codes. Yes I figured it wasn't supposed to be open, ?WHY? was my real quandary. I think it could possibly be the egr valve still, (valve has two springs maybe the lower tension spring is bad but not the bigger spring, allowing it to open a little when it shouldnt?). why or what would cause incorrect signal? (I believe mine does not have a solenoid, nor is it electronic?) egr hose connects directly to the throttle body which is actuated by operating pressure i thought?
on June 17, 2014
STOP overthinking it!
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