I have a 1998 Volvo s70 manual. My engine light came on this morning. Stopped at an auto parts store and the did a diagnostic for me finding it needs an Engine Coolant Temp sensor (AutoZone, #TU251 part). I need to know where that is on the engine, is there an on-line diagram to look at? How accessible is it? Could low anti-freeze cause this? When I returned home and shut my car off the engine cooling fan continued to run...also...I noticed the heat coming out of the inside vents cooled as I was coming home...my husband is thinking maybe it needs coolant...which is likely to be true...but would that have anything to do with the sensor going off and the code saying it was the Engine Coolant Temp Sensor? Thank you for your assistance.

SOURCE: Check engine light on and Troubleshooting code is P0116

Hi, I managed to find a graphic illustration of the ECT sensor.


Good luck!

SOURCE: Replace Heater Core for Volvo S70 (1999)

It is your heater core. I fixed mine for $144. Ordered the new part on Ebay and followed these instructions http://www.volvospeed.com/vs_forum/index.php?showtopic=9717 It was very simple, I'm a middle age grandmother! The hardest part was cleaning up all the antifreeze. You will need a shopvac, a small one is $20 at WalMart.

SOURCE: on my 1998 volvo s70 the floor is wet with coolant on the drivers side and when using the a/c you can smell freon and you can see a white fog coming through the vents

Your Heater Core is Bad= Coolant on Pass Floor
If A/C Does NOT blow Cold anymore the Evaperator Core is Leaking
First time I have seen them BOTH go Bad in 30 rs of Bein A Mech/Tech

SOURCE: Volvo Cooling sensor / fan arent working

My air conditioner or fan turns on when the car gets too hot. It doesn't happen every time but often enough to drain the battery. It is a 2001 Volvo S60 turbo. I don't know where to start.

Scott Young

• 91 Answers
• Posted on Aug 30, 2009

SOURCE: speed sensor volvo s70 1998. Is this an easy fix?

it is on the back side of the roter and yes it is easy to fix and no there is on special tools just undo the two bolts pull it off unpluge it and then put the new one on and have a good day

Testimonial: "Direct answer to a direct question. Replaced the paret in 5 mins. Thanks"