questforbalance

Just started up my 2002 Porsche Carrera C4S and got P0116 code and flashing temperature light. How do I diagnose and fix this? As a matter of reference, I recently changed the front radiators about a week or two ago. It has also been cold as heck here in NJ, could the cold cause this? Never had this problem before. Is it ok to drive with this condition?

questforbalance

I forgot to add that I took the car through an automatic car wash to get the road salts off. Never took it to a car wash before and may not do it again. Maybe the car wash damage the ECT?

fpb111

Did you check the coolant level? Did you use a UView 550000 to refill the system?
http://www.tooltopia.com/uview-55000...ricegrabber_r1

Ahsai

If you didn't use a vacuum tool, there could be air trapped inside the system. Diff blinking rates have diff meanings. Check post #4 here
http://www.renntech.org/forums/topic...erature-light/

Imo000

I'm on my phone and the search function sux. What does P0116 refereces to?

Ahsai

Coolant temp circuit range/performance

http://obdcloud.com/porsche/obd_trouble_code/P0116

Macster

Find the coolant temperature sensor and unplug the connector then connect it. Actually I'd have the car in a heated garage first as if you do this with everything really cold there's a risk of the insulation cracking due to age and cold temperature.

In a pinch you can warm this area up with a heat gun set to *low*. You want the wiring nice and pliable but you still want to treat the wiring very gently.

questforbalance

Hello Everyone, Thanks for the feedback. I checked the ECU with my Durametric and got four DTC codes: P0116, P0128, P0 430 and P0420. All seem to be related to the P0116 or ECT. I ordered a new ECT and will receive it on Tuesday. I compared the Intake Air Temperature with the Engine Temperature and the Engine Oil temperature on a cold and warm engine. When cold, the Intake air was 7 Celsius, the Engine Temperature was -3.2 and the Engine Oil Temperature was -2.8. When the car was warmed up after running for five minutes I got: the Intake air was colder than the other two readings. The Engine Temperature and the Oil temperature were between 20 to 30 Celsius.

I figured I was going to change the ECT since it is a cheap thing to change. While I am there I figured I would inspect the ECT wiring in my garage with space heaters on. Then I would wrap the wires with shrink tubing so that they can be better protected.

I also bought a new thermostat which I figured I would replace if the ECT replacement did not fix the problem. Obviously, I prefer not doing this stuff in the middle of winter.

When I changed the radiators, I had the hoses clamped shut so I took out less than two gallons of coolant from the two radiators combined. When I installed the new radiators, I filled them as much as I could before I completed the installation. I then filled the reservoir and ran the car for a while with the bleeder valve opened. I then drive it a few miles (i.e. 5 or 10 miles) and put in another 1/3 cup of coolant in and it remained steady for a week. Then I took it through the car wash because it was covered in road salt. Two days later I started up the car, warmed it up and turned it off. About four hours later I put the key in the ignition and I got the blinking coolant temperature light and the thermometer warming light on the dash. I think the car wash may have shorted out the ECT?

Any thoughts or suggestions?

questforbalance

Help! I changed the engine coolant temperature sensor, but am still getting the same temperature warning light on dash and flashing temperature warning light. Now what?

questforbalance

I worked on solving this problem today and so this is what I did:


I rechecked the new Engine Coolant Temperature sensor, inspected the wires and inspected the self adhesive tape I used to wrap the wires feeding the ECT sensor and the ECT (I wrapped everything up thoroughly). I then removed the B1 fuse from the fuse box just in case there was an air pocket left over from when I changed the front radiators three weeks ago. I opened the bleeder valve, cleared the DTC from the car's computer and bled the car all over again. I hooked up my hand held OBD2 reader and monitored the RPMs and engine coolant temperature sensor. After a few minutes the temperature sensor on the dash board starting working and indicating the coolant temperature. I compared the result with my hand held OBD2 reader. I spent a good 30-minutes reving the car and trying to bleed the coolant system. The car did not need any more coolant. I drove the car for about five miles and no codes returned, no flashing lights and the temperature gauge was working properly.


My theory is that the car wash may have shorted the ECT somehow and caused the coolant system to malfunction. Everything seems ok for now. Hopefully it stays this way. Thanks for everyone's help and I hope this posting helps others with the same problem.

Ahsai

Actually it's more likely an open circuit as opposed to short because the sensor is NTC type whose resistance decreases with heat.

Imo000

If it happened once it will likely happen again but maybe you got lucky.