Now that I think of it, the van accelerated on its own before the tuneup as well. It accelerated more than I would assume normal without gas pedal when I tested the brakes. Just never saw this code til now.
Everything is connected where it should be to the best of my knowledge.
Ok, here is where I'm at:
Blue: is areas I directly checked and were good. No leaks around intake manifold gasket, no leaks on blue lines, vacuum present and engine change where blue connectors were disconnected, ie working normal. Don't see cruise control on diagram, but its lines and connecters didn't react to spray. Both sides of PCV & brake booster line are normal.
Yellow: Did not check. I checked all of HVAC under center of dash, but a few lines went off behind glove box I didn't get to. Moved all HVAC controls to all positions, no change in RPM. Also, gas tank is full, so can't access on top of it now. Did not drop EVAP cans, but sprayed a lot on top.
Green: No Vacuum present, no change unplugging them. The EVAP vent did nothing when sprayed directly. the service port did nothing, and the rearward line off purge solenoid had no vacuum or change when disconnected. I'm guessing since neither of those did anything, they pretty much cover all the gas tank lines I couldn't get to anyways. I'm assuming they only get vacuum(or leak) when that purge solenoid activates anyways, so probably normal operation.
Orange: I'm not sure which is MAP sensor. Front of throttle has one vacuum line only for EVAP. Rear has IAC valve, drivers side has 2 sensors, unsure which is MAP, both appear flush on throttle, no vacuum line there anyways...
Red: possible leak. I went through 1/2 can throttle cleaner, full can starting fluid, 1/3 can brake cleaner. Tried someones dumb idea of WD40, but that's way too flammable near exhaust... I sprayed every line and fitting except glove box area, and over gas tank. Did water once I ran out of chemicals.
Out of all that, I thought once, the engine changed speed where I have circled red. All 3 of those lines are in the valley between intake man & drivers valve cover. Thought engine bogged down once while spraying there. Removed all the plastic wire loom shields(grey outlined) off those 3 lines, sprayed again, and bogged once (I think). When I moved lines out of the valley, none would set it off sprayed individually. intake manifold under them wouldn't do it either. I'm not even positive I heard anything, it was barely a change in RPM (my imagination?). Can't feel any cracks or see any problems on lines. Seems 98% leak free, real hard to tell so far.
I reset the code for now in case it was just a fluke incident, but I'm guessing creeping forward up to 25mph without gas pedal input is not normal. Still does it today without a code present(yet).
What should I check next?
Also, can I just cap off some of these lines right at the intake manifold to test everything but one section at a time? Or will that cause any vacuum issues to interfere with troubleshooting?
Can I run a short hose to bypass the EVAP solenoid(like a constant completed circuit) to check vacuum further back on EVAP lines that didn't have vacuum previously without solenoid on?
Would butane or propane make a more noticeable RPM change on a leak?