94SLUG

Would any part of the system control the idle at all? Trying to track a low rpm stumble/surge...

MTBSully

im not positive, but i doubt it. Many people including myself have done away with the EVAP system all together. Its really just to ensure that you dont smell gas around the car.

shoebox

The EVAP system does not engage at idle- only when you are moving.

Injuneer

If the EVAP solenoid is stuck open with carbon, you might have an idle problem.

System is there for emissions purposes. A fringe benefit is it reduces fuel odors.

94SLUG

For removal just disconnect solenoid, vacum cap tb? Thats what I did, which means the surge is from another area.... More looking and no codes..

eric z28

ya mine has idle surge when warm too....runs perfect when cold up to about say...185f...disconnected o2 sensors but still does it in gear at stop, however stick in n and car idles decent, although it runs pig rich...got a few wiring issues iam in process of cleaning up, cracked insulation and poor terminal connections mostly...o2 sensors switching fairly dece3nt according to snap on brick scanner,,,,not too much data on it tho...tps reading steady, maf sensor just replaced, plug wires, plugs too(autolight platinum) not too sure about those tho, would rather have delco, seems either lean missfire causing surge problem due to block learn multiplyer trying to fatten up system....o2 sensors reading predominately lean while surging...car seems to start surging when it attempts to idle at desired idle speed of approx 650 according to scanner...drops down to about 850 then misses on a cyl or two then surges up to 1200-1500 rpms and repeats pattern until pull away from stop...also starts missing badly at 1/3 throttle sudden load....lean? or ignition missfire? no miss at wot tho...having hard time telling if it cutting out spark or if i losing fuel...rite now i am leaning towards pressure regulator....also, blocked off egr at intake side in order to eliminate vacuum leak possibility....anyways...it starting to **** me off everytime i sit in stop and go traffic....any help would be greatly apprciated....thanx ya'll