Problem throwing the same code... I give up
07-22-2016, 01:28 AM
#1
Problem throwing the same code... I give up
First off the car a 1996 CE LT4 starts instantly and runs and drives perfect but the SES has been on throwing a P0118 code. So I replace the sensor in the water pump and clear the code. 5min later the same code makes the SES light come on again.
Before I replaced the sensor and after the car won't start when warm or hot unless I put the gas pedal to the floor and it starts idles at 2200rpm and slowing comes down.
Does this sound like the ICM? I don't understand I replaced the sensor so why is it still throwing the same code.
Oh and the harness is fine and it's getting 5.3vDC.
I'm just out of ideas other than replacing the ICM but wanted your opinion before I spend $100.
Before I replaced the sensor and after the car won't start when warm or hot unless I put the gas pedal to the floor and it starts idles at 2200rpm and slowing comes down.
Does this sound like the ICM? I don't understand I replaced the sensor so why is it still throwing the same code.
Oh and the harness is fine and it's getting 5.3vDC.
I'm just out of ideas other than replacing the ICM but wanted your opinion before I spend $100.
07-22-2016, 12:50 PM
#3
Team Owner
Pro Mechanic
You already did play the guessing game by throwing a sensor at it. That didn't work. There is more to diagnosis than replacing the sensor that an DTC is referencing.
Test (ohm) the sensor. Test the harness for continuity from the sensor to the ECM. Report back.
.
Test (ohm) the sensor. Test the harness for continuity from the sensor to the ECM. Report back.
.
Last edited by Tom400CFI; 07-22-2016 at 12:52 PM.
07-22-2016, 02:39 PM
#4
Racer
tom 400 is right,, i had the same problem and my problem was 2 fold, new sensor was not good enough,,, and a loose connection on the connector to the sensor . do a scan if you have a -400 then you have an open, of course your car would run crappy or hard start..
07-22-2016, 04:56 PM
#5
Tested the harness I have the 5volts and continuity? But when I have my scanner plugged in it shows ECT -40 degrees so I haven't a clue what's that about. And the gauge is spot on its not like the gauge is acting crazy.
Before I put this one in I checked the ohms at room temperature then put the tip in simmering water and checked again and they both correlated for a graph I saw on here once.
The harness terminals look like new so I know it's not a bad connection.
It's just the live data thing that has me stumped... does anyone know if they will pass/fail a nys inspection just for this one stupid code.
Before I put this one in I checked the ohms at room temperature then put the tip in simmering water and checked again and they both correlated for a graph I saw on here once.
The harness terminals look like new so I know it's not a bad connection.
It's just the live data thing that has me stumped... does anyone know if they will pass/fail a nys inspection just for this one stupid code.
07-22-2016, 05:27 PM
#7
The sensor is good I had it at different Temps and checked the ohms and it correlated with a graph I saw on here.
Should I get a new harness and cut the old one out and splice it in?
Should I get a new harness and cut the old one out and splice it in?
07-22-2016, 05:57 PM
#9
Melting Slicks
Member Since: Aug 1999
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If so you press that button until you see temperature of the Engine Coolant Temperature sensor displayed in the Dash Cluster LCD.
The dash temperature analog gauge uses a different sender.
07-22-2016, 06:24 PM
#14
I just dont understand how the gauge can work perfectly but its still throwing the p0118 code. Also i dont know if this means anything but the digital gauge doesnt go past 193 degrees.
07-22-2016, 06:40 PM
#16
The harness connectors are nice and shiny with a tiny bit of di electric grease on it. I tested the one side and got the 5v the othe side do i just test the continuity from the harness to ground from the harness to the ecm ”box” or a certain pin when you remove the ecm harness?
07-22-2016, 06:56 PM
#17
Team Owner
Member Since: Mar 2001
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I'm sure there is, that's where my knowledge ends
Careful on the ECM connector, they get fragile with age
One of my clips has already broken from getting brittle.
Careful on the ECM connector, they get fragile with age
One of my clips has already broken from getting brittle.
07-22-2016, 07:51 PM
#18
Thanks for everything. Alot of people have been saying the harness may be bad but if that was true wouldnt the temp gauge not work. The fact that the temp gauge works to me means the signal is making it back to the ecm.
I wonder if the ecm could somehow be bad.
I wonder if the ecm could somehow be bad.
07-22-2016, 10:42 PM
#19
Race Director
The analog temperature gauge uses a CTS (Coolant Temperature Sensor) in the passenger side head. The ECM uses a CTS in the water pump. The ECM is the source for the digital temperature display.
07-22-2016, 11:35 PM
#20
Yes I know all of that, it'sy fault but anytime I said gauge I meant the digital gauge, it has never been out of whack once. My buddy has a 1996 lt1 corvette I think I'm going to try switching ecm's and see what happens.