Cold Start Valve

[Pritchard]

I have a stock "74 2.0L engine. I have a few questions regarding cold starting.Last night the air temp was about 40 degrees. So I figured it would be a good time to test the cold start valve. I removed the CSV from air intake distributer, leaving fuel line and wires connected, and placed it in a vial. I then tried to start the car, w/o the coil connected of course. No fuel came out of the CSV. So I plugged in a FI connector to the CSV, tried to start the car, floored the gas pedal, again no fuel through the CSV.

I checked the resistance of the CSV and got 6 ohms. My questions are: 1-have I tested the CSV sufficiently, and 2-what should the resistance of the CSV be? Is it 2.4 ohms like the injectors?

By the way, three injectors are reading 2.3 ohms and one injector is reading 2.2 ohms. These values are below what is recommended. Are they too low?

Another question just popped in my head. If the Temp Sensor #1 is on top of the air intake distributor, what is the sensor located on (NOT IN) the block just to the right and in front of the air intake dist.? It is a single wire sensor. This thing is a big sensor. I got no reading when trying to get the resistance from it.

Thanks for any and all advice.

PRITCHARD

[Dave at Pelican Parts]

The best way to test the CSV is to provide +12V to one of the pins in its connector, and a ground to the other pin. Then look to see if it squirts fuel. I'm not sure what the resistance is supposed to be.

The sensor you've found is the thermo-time switch. This one sits kinda horizontal, on a bracket off the right-front of the manifold, right? Then it is the TTS. This switch controls the operation of the cold-start valve.

The CSV works if and only if two conditions are met: 1-if the yellow wire going to the starter solenoid has +12V, and 2-if the TTS provides a ground.

The TTS usually is an open circuit--no connection to anything. When it gets "cold enough" (not sure how cold that is; I have heard numbers from 50F - 30F), the switch closes and the single wire going into it is shorted to ground. (This is by way of the switch's housing and the bracket to the manifold to the engine case.) So it may simply not be cold enough to trigger the TTS, which would prevent the CSV from working.

I am not certain about the resistances of the injectors. I don't know how critical they are; I presume that "anything in the general range" would be OK. But I'm not certain about it.

--DD

[John Rogers]

An added bit of info, if the wire drops off the TTS and grounds against the engine, the engine will stop..... We had an intermittent stopping problem and the wire had come loose and would briefly touch sheetmetal and cause the engine to stop and then it would restart????? A new connector fixed it.