Started it up yesterday and it would stall and wouldn't idle smoothly, after keeping on the gas for abit it smoothed out and got a little better. I then got a code 15. Anyone have any ideas? 305 TBI

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88'Camaro
305 TBI

 

did you check the tech section to see what that code was?
I think that is a CTS failure but dont take my word for it

 

I checked what the code meant:
"Low temperature indicated at engine coolant temp. sensor"

So does anyone have an idea what this means?

 

Yes, there's a problem with the connector at the coolant temp sender or in the harness. The ECM will be in open loop all the time because the coolant temp is too low. This code only sets after about 2 minutes of driving right????

The ECM will run off pre programmed tables on the prom. Your fuel economy will really suffer.

Check the sensor/connection/harness

Marck

 

actually i get the code about 15 seconds after i start the car, that is if i manage to keep it going. Once i get it warmed up abit it runs pretty decent, but still rough

thanks for the help, i'll check those connections.

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________________________
88'Camaro
305 TBI

 

A new CTS should run you around $8 so if you don't find a problem with the wiring, it's a cheap thing to try.

I had this problem when I had been testing sensor voltages... I had put the voltmeter probe into the connector socket, lo and behold I'd flattened out the contact in there so it wasn't pressing tightly against the sensor's pin any more. A little work with a needle to bend the connector tab back up and I haven't had the code since.

Take an ohmmeter and measure resistance across the terminals of the CTS. 177 ohms = 212F, 467 ohms = 158F, 1459 ohms = 104F, 2796 ohms = 77F, 5670 ohms = 50 F, ..., 52700 ohms = -22F. These are approximate.

If it reads way low or way high, your CTS is probably bad. If it reads about right, it's probably a wiring issue. Check that there's 5 volts between the yellow (positive) and black (ground) wires in the connector for the CTS. Then make sure the connector really is good :-).

Also the CTS shares a ground with the TPS and MAT/IAT sensors. So check their connectors too if you don't find any other problems.

 

thanks, i'll give that a try and see what happens. Appreciate your time

jon