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I pulled the codes from the ECU and it went (Flash..Flash 2.5 sec delay Flash..Flash) I am guessing that is code 22 from what I have read.

My problem is that after 5-6 min of driving my check engine light will come on and my truck will begin stalling, loosing power, and often dying at lights. Would a bad coolent sensor realated to code 22 cause the truck to die at lights? If not does anyone have ideas of what else it might be. Someone suggested it could be a bad oxygen sensor but I did not get a code 25 when I pulled the codes.

I did notice that I need a new radiator cap, the old one dried up and cracked. Since a small amount of fluid is leaking through the cap could this cause a faulty read from the sensor and trigger a code 22. If not, how difficult is it to change the coolant sensor and will most places (Auto Zone, Oriely, etc.) carry them is stock.
 

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rookie
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796 Posts
the coolent temp. senser that sends infermation to the ECU ( not the one that sends infermation to the temp. guage) would cause that , because its confuzzled like and it lies to the ECU and the engine suffers the sonsequence of a lying coolent senser and dies.
 

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YOTA Master
'93 2wd P/U
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2,434 Posts
pee_cup's way of saying things is......

Always refreshing...
pee_cup said:
the coolent temp. senser that sends infermation to the ECU ( not the one that sends infermation to the temp. guage) would cause that , because its confuzzled like and it lies to the ECU and the engine suffers the sonsequence of a lying coolent senser and dies.
This is a good analogy.

With that code, and the symptoms you've described, you certainly could have a bad Coolant Temperature Sensor. However it would be prudent to check the circuit before throwing one on it. A bad connection or other wiring problem (ie, rubbed through wires) could also cause your code and symptom.

I would check the voltage at the ECM THW connector pin by backprobing before and during your symptom. When fully warmed up (about 185deg F) you should find about 0.5V at that terminal. During your symptom I would expect to see really high (near 5V) or really low (near 0V) If it is low disconnect the sensor and see if it goes to about 5V. If it is too high during the symptom Disconnect the sensor and short the wires together and the voltage should drop to 0V If this happens replace the sensor. If not then the problem is in the wiring.
 

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rookie
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On one of my other cars I had a break in the wiring right AT the harness where the wire entered the plastic body of the coolant temp. sensor harness, I had to peel back the rubber boot to find that it was all corroded and shot. sneaky bugga
 

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pee_cup's way of saying things is......

Always refreshing...

This is a good analogy.

With that code, and the symptoms you've described, you certainly could have a bad Coolant Temperature Sensor. However it would be prudent to check the circuit before throwing one on it. A bad connection or other wiring problem (ie, rubbed through wires) could also cause your code and symptom.

I would check the voltage at the ECM THW connector pin by backprobing before and during your symptom. When fully warmed up (about 185deg F) you should find about 0.5V at that terminal. During your symptom I would expect to see really high (near 5V) or really low (near 0V) If it is low disconnect the sensor and see if it goes to about 5V. If it is too high during the symptom Disconnect the sensor and short the wires together and the voltage should drop to 0V If this happens replace the sensor. If not then the problem is in the wiring.
Most excellent direction! I went through the checks you suggested: Yes, I had a constant 5V at THW and E2 lno matter what the temperature, so pulled the connector at the sensor and shorted the leads to check continuity. Voltage dropped to 0.0. While I was at it I ohmed each of the two wires from the connector back to the ECU...all good. So, it must be the senor.
Pulled the sensor this AM, and I can get just over 2000 ohms across the terminals, which will drop down to around 800 or maybe less when heating the sensor with my zippo. Without knowing what the resistance "should" be, I wonder if the sensor is indeed working correctly after all....though the plstic connector top is loose which may cause some weird action. New sensor on order....guess we'll see.
 
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