On a quick reference in the 110 manual, 07.3.2 11a-140/9, looks like the fuel pump relay supplies power to the warm-up compensator off pin 7 via a 0.75 black/green/white wire...
Section 'D' in the 07_3-500 PDF. The other culprit *may* be the decel valve..
Wiring is section E
There should be 2 little valves on the firewall with vacuum ports. to test the decel valve you disconnect the top lines from the valves and plug the lines together while the engine is running. if the engine stalls then the decel valve should be working OK.
You can remove it and spray it with carb cleaner, then spray a bit of silicone lube in it to make sure it works OK. or mity-vac it to test..
Whats the cold control pressure and whats the warm control pressure? As someone stated, WUR is powered by fuel pump relay. Is your control plunger sticky? What about vacuum leaks? And pinching AAV hose like djenka said when cold is good way to knock that off suspect list.
WUR is only going to change the mixture. If the mixture is off the idle speed will most likely go down or possibly up by no more than 10%. Sounds like air is getting by somewhere.
Try eliminating external air sources by pinching off vac lines.
Power booster
Charcoal canister
Especially any vacuum lines controlled by relays or thermo switches.
Thanks for the suggestions, everyone. Obviously you can't possibly have been following my whole history on The PIG's issues so I'll just say....been there and done all that.
I changed the plug end on the WUR harness and idle dropped in 150 seconds (as per).
Then it stalled. I had it WAY leaned out to overcome the WUR.
I'll see tomorrow when it's back to cold....but for now....it seems like it is right.
Wow. Congrats on tracking it down. Thank you for learning it the hard way and sharing it with everyone else... so we don't need to also learn it the hard way.
Fuel and air delivery systems are all brand new....and ignition 75% done.....still have the original distributor.....but I have 2 spares to muck around with.
Not really. If it looks good and it has 12V...then why bother?
I replaced that plug end 7 years ago because it was rotten. It lives in a bad place on the M110...subject to more abuse than if it was on top of the engine.
7 years later it was rotten again and only working intermittently.
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