LT4 with unstable coolant temp. readout
Thread Starter
Melting Slicks
Joined: Jul 2004
Posts: 2,295
Likes: 14
From: Grand Sport #82
LT4 with unstable coolant temp. readout
My LT4 have had a strange issue where the digital temperature suddenly would go to near 0 degree C and then start to oscillate up and down in temperature from 0-80-ish degree C. When it did the car would run very rough and rich, and be very hard to start.
The analog gauge show a rock steady temperature.
I replaced the sensor in the WP with no change, but then I discovered that the issue could be provoked by moving around with the 2 wires going from the harness at the fuel rail to the sensor. I find no sign of wire damage so I pinched the connector female connector’s a bit, and it have been running with no issue for 2 days now.
But, cruising on the high way I normally see 83 degree C, but it will sometimes move a bit around, between 80-86 Degree C, not as fluctuation, but slow changes in temperature while cruising.
I have not noticed this before, and would that be normal?
Car has a PCM tune and lower temperature T-stat wth BeCool radiator.
The analog gauge show a rock steady temperature.
I replaced the sensor in the WP with no change, but then I discovered that the issue could be provoked by moving around with the 2 wires going from the harness at the fuel rail to the sensor. I find no sign of wire damage so I pinched the connector female connector’s a bit, and it have been running with no issue for 2 days now.
But, cruising on the high way I normally see 83 degree C, but it will sometimes move a bit around, between 80-86 Degree C, not as fluctuation, but slow changes in temperature while cruising.
I have not noticed this before, and would that be normal?
Car has a PCM tune and lower temperature T-stat wth BeCool radiator.
Last edited by Lars87; Sep 10, 2014 at 06:16 AM.
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
The temp sensor is failing. Replace it before it leaves you stranded.
Here is the hard part... the parts I have bought of recent years have been garbage. I have had new out of box parts fail.
You may want to try ACDelco or Infineon. Stay clear of BWD... Wells isn't bad, either.
Here is the hard part... the parts I have bought of recent years have been garbage. I have had new out of box parts fail.
You may want to try ACDelco or Infineon. Stay clear of BWD... Wells isn't bad, either.
