1998 V70r Temp Gauge reading hot at startup

Post by **chexny** » 07 Mar 2014, 19:03

I just went to get ATF for my p/s issue (https://www.matthewsvolvosite.com/forums ... =1&t=62077) and the following happens.

3 mile drove to the store. Park spend 20-30 minutes inside. I start up the car, pull out of the parking lot and stop at a light a few hundred feet down the road. I look down and see the temp gauge reading max heat. Considering it is cold out and the car has been running for all of 1-2 minutes max at a low speed I am confused. I immediately pull into a gas station. Shut off the car and notice the fan is still running. It runs for 3-4 minutes and turns off.

Coolant is low but right at the min line. I do have a small leak as I have had to add fluid a couple of times this winter but not a ton. Both the radiator and heater core were replaced within the last 2 years by a local mechanic who only services Volvo. The radiator at least I know is not Volvo but rather an after-market Belgium (I believe) brand - he just told me it was high quality and not cheap after-market stuff and it saved me about a $100 or so I think.

Anyway, I wait a 10-15 minutes after that then add some coolant.

I start up the car and the gauge immediately rockets to max. I decide to drive home the 3 miles anyway. After I pull out the gauge starts to move back toward the middle but after 1/2 mile or so creeps back up to just under max. And then slowly moves up to max. After I get home the car, I shut off the car and the fan is running for 3-4-5 minutes again and finally shuts off. About 30 minutes later I put the key in the ignition without starting the car to see the temp and it was reading just under the mid level. There is not any noticeable heat radiating off the engine or anything and I don't think the motor is really all that hot at all. Oil was fine and just changed within 200 miles or so.

Is this just a thermostat issue? Is there something else. I know I need to get the radiator checked b/c of the leak I just don't want to spend a ton of money that I don't have. The leak is fairly slow but if anyone has a suggestion for that as well I would appreciate it.

Also, I have a 200 mile round trip in the morning. Anyone think I can chance it or does this sound like something I need to have looked at first? This is the first time I noticed this issue and every other morning the car was cold at start-up and warmed up after normal few minutes.

Klausc · Post by **Klausc** » 07 Mar 2014, 19:58

If you have an aftermarket thermostat, it doesn't work anymore. If it were my "R", I would rent a car.

Post by **rspi** » 07 Mar 2014, 22:27

There is a good chance that your car temp is fine and the gauge is getting bad info from the ECT. It will often cause the fan to run after the car is off.

Do you have a OBD2 tool that can read live data? If so, hook that up first thingin the morning and see what it claims the temp is. If higher than 100°, you will know that something is wrong in the temperature reporting system. If it is off, it may cause the car to run rich or lean, which can cause a valve to burn on a long trip.

May be best to park it until you fix it.

Post by **rspi** » 07 Mar 2014, 22:29

Post by **erikv11** » 07 Mar 2014, 23:12

+1 to rspi.

You could pull the thermostat just to be positive, but almost for sure the problem is the ECT sensor. The thermostat is probably just fine. I would not drive it like this though, temperature issues are too risky.

Post by **BEJinFbk** » 08 Mar 2014, 00:34

+1 - Park it.
Rental Cheap!
Fresh Head Expensive...

Post by **chexny** » 08 Mar 2014, 05:31

Thanks everyone. I did start it up again and the temp gauge read cold warmed up normally. However I am going to park it for now and replace the ect/thermostat and see how it goes from there.

rspi - thanks for the video. Spent a couple of hours reading posts and watching videos last night and found your youtube page and watched that video. Very much appreciated.

Post by **chexny** » 08 Mar 2014, 15:16

I am trying to order the parts. Do I want an 87 or 90 degree thermostat?

Post by **rspi** » 09 Mar 2014, 13:09

I usually get the 90.

Post by **chexny** » 10 Mar 2014, 20:28

Quick update -
I drove the Volvo the other day to the parts store to get the code read - on that drive the CEL came on. Note it had not come on before. It read P0116 which I understand is the ECT.

I changed the thermostat and ECT. During the process some coolant spilled out when I pulled out the thermostat but really not much at all. Also my battery was dead from the fan running. I used a battery charger/starter I have. The minute I connected the charger to the battery the fan started running. I started the car. The temp gauge was cold, it warmed up fine. However the CEL was on. There was a fair amount of smoke coming from the area where the coolant spilled. It seemed way more than it should if it was just the coolant. I watched RSPI's video on PCV system and pulled the dipstick and it had a steady white smoke coming out. It's sadly going to the mechanic because this is beyond me.

Thanks again. Pretty sure this one is going to sting.