Cold Start Valve fires when hot.

[dmcnc]

Greetings from Florida!

I've been having Hot Start Flooding issues for a while. My Cold Start Valve engages on crank regardless of engine temperature. I tested the Thermal switch with a multimeter and the W and G ohms looked good for above and below 95F categories so my guess is it’s working correctly: over 100 Ohms when hot. With the CSV disconnected, car requires open throttle when cold (as expected), and starts up like a dream when hot (doesn't requires an open throttle). I pulled the CSV out, plugged the air pipe, and placed the CSV in a bottle for testing. The Hot-Start relay is not jumped.

Results:CSV activates when car is cranked even under hot conditions. CSV, however, does not leak fuel at all once you let go the crank, which tells me the valve is working as its told. The active CSV on hot starts has been flooding my car for a while. Question is, what's making it go off with the starter under hot start conditions if the TTS is working correctly? Is there any way/where CSV and starter circuits could cross?

-Rafael

[content22207_2]

Try to ring the other TTS terminal (Blue/Black) to ground (body of the pump) when the coolant is hot. If it rings through, the TTS isn't breaking contact in response to hot coolant temperature.

Whenever Blue/Black is grounded through the TTS the cold start injector will spray while cranking (Red/White).

The TTS uses a bimetalic strip to make and break contact, just like an old fashioned turn signal flasher. Wouldn't surprise me if that strip eventually wears out just like an old fashioned turn signal flasher. Only difference: replacement turn signal flasher only costs a couple of dollars.

Bill Robertson
#5939

[dmcnc]

Try to ring the other TTS terminal (Blue/Black) to ground (body of the pump) when the coolant is hot. If it rings through, the TTS isn't breaking contact in response to hot coolant temperature.

Whenever Blue/Black is grounded through the TTS the cold start injector will spray while cranking (Red/White).

The TTS uses a bimetalic strip to make and break contact, just like an old fashioned turn signal flasher. Wouldn't surprise me if that strip eventually wears out just like an old fashioned turn signal flasher. Only difference: replacement turn signal flasher only costs a couple of dollars.

Bill Robertson
#5939

Hi Bill! Just rang the Blue/Black TTS terminal with the water pump body once the car warmed up and got a reading between 120-130. The other terminal reads 60.

-Rafael

[content22207_2]

Put your meter on the beeper setting and see if it rings through. If it does, your cold start valve will fire (whenever Red/White is energized).

Bill Robertson
#5939

[hmcelraft]

You might want to check and be sure the fuel CPR wire and the cold start wire are not switched.

[dmcnc]

Bill - I had it under continuity test mode: FullSizeRender.jpg
No beep when hot, only the readings above.

- break -

Funny those two connectors are interchangeable, but yes, I do have the blue on CSV and black on CPR.

[content22207_2]

Did it beep? If the meter beeps, TTS is conducting well enough to close the circuit.

Bill Robertson
#5939

[spikeygg]

I just checked mine (I'm having cold start problems as well). Is the top wire supposed to be Blue/Yellow and the bottom wire supposed to be Blue/Black? That's what mine are. With a cold engine I probed the top prong (Blue/Yellow) of the thermo-time sensor and it was 30Ω to ground/body of the sensor. I probed the bottom (Blue/Black) of the thermo-time sensor and it was a 0Ω short to ground/body of the sensor.

Anyone know if this is acceptable? Also interested in the values of a functioning engine when hot if available.

Thermo-time Switch.jpg

[dmcnc]

Did it beep? If the meter beeps, TTS is conducting well enough to close the circuit.

Bill Robertson
#5939

Did not beep.

[dmcnc]

I just checked mine (I'm having cold start problems as well). Is the top wire supposed to be Blue/Yellow and the bottom wire supposed to be Blue/Black? That's what mine are. With a cold engine I probed the top prong (Blue/Yellow) of the thermo-time sensor and it was 30Ω to ground/body of the sensor. I probed the bottom (Blue/Black) of the thermo-time sensor and it was a 0Ω short to ground/body of the sensor.

Anyone know if this is acceptable? Also interested in the values of a functioning engine when hot if available.

Thermo-time Switch.jpg

That should be fine under cold conditions (under 95F):
The resistance value between "G" and ground should be:

At a temperature below 35 degree C: about 20 Ohm.
At a temperature above 35 degree C: about 60 Ohm.
The resistance value between "W" and ground should be:

At a temperature below 35 degree C: 0 (zero) Ohm.
At a temperature above 35 degree C: about 100 Ohm.

Ref: http://www.sl113.org/wiki/Engine/ThermoTimeSwitch