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ossiblue ossiblue is offline
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Join Date: Oct 2005
Location: Capistrano Beach, Ca.
Posts: 7,235
Quote:
Originally Posted by tkmoore View Post
Guys, I know I'm coming at this issue in unconventional manner but I'm working on a warm start issue on my 83 SC. I had WUR fixed and adjusted by a good shop last fall to fix cold start problem. Now upon warm start, car quickly dies if hot, or if semi cooled idle fluctuates up and down for a few minutes then eventfully idles stray as it should. I've not got access to guages right now to check pressures, but I've checked for vacuum leaks (seem to have none) and scoured the fuel lines for leaks(finding none). Studying my Bentley I started checking my Cold Start Valve system today. On warm start today car had same symptoms but as soon as I unplugged the CSV it idled fine. Does this indicate a bad CSV or is it likely the thermatic temp switch is telling the CSV to spray fuel improperly? I appreciate the help as I'm still learning about the CIS. Thanks,
Could be either one.

Unplugging the CSV removed both power and ground circuits to the CSV so unless the valve was stuck open or leaking, it would provide no fuel. That solved your issue, but leaves you without knowing the culprit.

Next time, disconnect the wires from the thermotime switch, preferably just the red/black one. That is the ground circuit to the CSV, but the CSV will still be getting power through the yellow wire at its connector. If that fixes your issue, then the thermotime switch was the faulty part as it was not breaking the ground circuit, when warm, as it should.

If the issue remains, then either the ground wire that you disconnected is shorting to ground (allowing the CSV to operate)or the CSV is faulty and is grounding itself.

BTW, you can do an alternate test with a trouble light or multimeter. With the engine fully warmed, unplug the connector to the CSV. Connect one lead of the light/meter to a power source, and touch the other lead to the socket in the connector for the ground (red/black wire.) You should get no light/reading. If you do, the wire is still grounded and either the switch or the wire is faulty. Repeating the test at the switch itself (with the wire disconnected) will tell you if the switch is bad.
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Last edited by ossiblue; 04-18-2015 at 07:01 PM..
Old 04-18-2015, 04:21 PM
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