Odd temp sensor issue

berk850 · Post by **berk850** » 18 Jul 2010, 14:59

Hi.
The car is a 1996 850 T5 2.0 auto (same as the regular T5 other than the smaller displacement)

I am having an odd issue with my car since thursday. The temperature needle in the dash started fluctuating last week so I changed the sensor. Now the situation is that:

-The car starts fine when cold but the temp needle reaches 3 o'clock position within 10 seconds!, it even does this when I test with the temp sensor unplugged.
-When starting warm the needle takes a long time to reach 3 o'clock position despite the engine being warm. It therefore does not start easily, I need to press the gas pedal for it to start and keep the pedal slightly pressed till the needle moves up, otherwise it dies. I think it thinks the engine is cold and therefore has a rich air/fuel mixture. When the needle reaches the right position it idles fine.
-I have the same issues even when test the car with the old sensor! I did not have these problems before. What do you think causes these problems? Can anybody make any sense of this?

I need to fix this before a long trip I need to take on wednesday.

Thanks in advance.

Post by **Ozark Lee** » 19 Jul 2010, 07:55

Welcome to MVS,

Since you changed the sensor and you continue to have problems the fault must lie with the connector or the wiring from the connector. I think I would start by spraying the connector with contact cleaner.

...Lee

berk850 · Post by **berk850** » 19 Jul 2010, 09:04

Thanks. I sprayed the temp sensor connector along with the ECU connector. The thermostat is also relatively new and the system is bled out. The problem seems to be in the wiring harness someplace but I have no idea how to localize the problem.