I have a 84z 305 H.O carb, I’m getting a code 15 which means CTS but I cannot find it. I looked at the thermostat housing and there are 2 sensors plugged into it and there is a sensor on the intake on the left looking st the engine of the housing. But its connected to the canister right in front of it. Is this the CTS? The connector looks nothing like the one I got from Napa. Any ideas?
NoEmissions84TA
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That is it. The CTS was redesigned due to the wires in that connector getting bent over by a hose IIRC.
The result is an intermittent in the CTS circuit and you get a CEL and error code.
You need to also buy a pigtail that matches your new sensor.
The result is an intermittent in the CTS circuit and you get a CEL and error code.
You need to also buy a pigtail that matches your new sensor.
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There are at least 2, maybe 3:
The one in the photo is the one that the ECM uses. Code 15 points to that one. Thermostat housing; yellow & blk wires. As GD says, new ones come with a new pigtail. The old kind is a total steaming POS, the new one is MUCH better. If you have any doubt at all, replace it all. Yours looks like the original and therefore needs to go in the trash immediately and get replaced. SOLDER the new wires in place w/ heat-shrink & tape, NOT crimp connectors.
The temp gauge one is in the driver's side head between the #1 & #3 spark plugs. Single green wire. Only works the gauge.
If your car has the L69 motor (VIN code G) the fan switch is in the pass side head; same hole as the above, just on the other side. Between the #6 & #8 plugs. It turns on the fan when it gets to about 23x°. Probably 234 - 235° by design, 230 - 238° normal tolerance.
Why do you ask? (besides just the light)
The one in the photo is the one that the ECM uses. Code 15 points to that one. Thermostat housing; yellow & blk wires. As GD says, new ones come with a new pigtail. The old kind is a total steaming POS, the new one is MUCH better. If you have any doubt at all, replace it all. Yours looks like the original and therefore needs to go in the trash immediately and get replaced. SOLDER the new wires in place w/ heat-shrink & tape, NOT crimp connectors.
The temp gauge one is in the driver's side head between the #1 & #3 spark plugs. Single green wire. Only works the gauge.
If your car has the L69 motor (VIN code G) the fan switch is in the pass side head; same hole as the above, just on the other side. Between the #6 & #8 plugs. It turns on the fan when it gets to about 23x°. Probably 234 - 235° by design, 230 - 238° normal tolerance.
Why do you ask? (besides just the light)