tentonhammer 10 Posted January 27, 2012 Temperature warning light comes on (flashes slowly) at start up and stays on for duration of drive. Temp guage is fine (I think) and gets no hotter than 90 degrees. Fan spins up as it should. Fault is intermittent - One day it continuously flashes, the next it doesn't? Done the basics, will look into this more on the w/e: Checked coolant level. All ok. Checked hoses. All ok. Checked dash warning indicator lights fuse. ok. Recently repaired wiring to ISV connector block, cleaned terminals etc. Car idles perfectly. Any ideas? Ten Ton Quote Share this post Link to post Share on other sites
VR6Pete 0 Posted January 27, 2012 (edited) Isnt the temp warning light the as the water level? IF so: what if you bridge the contacts on the plug on the header tank? sometimes the terminals in the header tank get gunk of them so it doesnt actually 'short' it out, thus thinking low water.... Edited January 27, 2012 by VR6Pete Quote Share this post Link to post Share on other sites
tentonhammer 10 Posted January 30, 2012 ahaaaa... Sounds plausable. I'll check it out and get back Quote Share this post Link to post Share on other sites
VR6Pete 0 Posted January 30, 2012 At least im hoping so :) Reason I say is because my temp guage has just packed in... (total coincidence while doing my OBD2 upgrade, my coolant light contantly flashes eventhough there is continuity between the plug and fuse board etc...) Vince @ stealth tells me that the 2 are related. so hoping when i replace my temp guage, it goes off :) Cheers Quote Share this post Link to post Share on other sites
swiftkid 1 Posted January 30, 2012 Another thing to check is are your heaters hot? Could be an airlock, mine had an airlock which meant my heaters would get luke warm but not hot and the light was merrily flashing away, if after you try pete's way you are still having problems trying removing the top pipe on the header tank and making sure its pointed upwards above the header tank whilst the engine is running to see if any air comes out. I think thats how you do it anyway, either that or take the top cap off and let it run for a short while (don't let it overflow madly) whilst pumping the top hose. I'm sorry if that advice is total garbage, I'm going from memory and its a mix of VR6 and valver memory! Quote Share this post Link to post Share on other sites
boost monkey 0 Posted January 30, 2012 Yeah it's normally the sensor in the top of the header tank that packs up. Quote Share this post Link to post Share on other sites
ChrisL 18 Posted September 24, 2012 My light has started flashing sometimes. Sometimes it's from cold startup other times it Akers a while. Plenty of water in the tank and temp gauge works fine. About a thousand miles ago I had the water changed at vw during a service and a new header tank fitted. Can the sensor in the header tank be changed or is it part of it? Quote Share this post Link to post Share on other sites
swiftkid 1 Posted September 24, 2012 Its part of the header tank I believe, could it be that there is an airlock in the system? you could try running the car (from cold) with the expansion cap off for a short time, don't let it overflow just run the engine for a few minutes. Otherwise you could have a duff sensor, or a bad connection, maybe wd40 it and clip it back on securely. Quote Share this post Link to post Share on other sites
ChrisL 18 Posted September 24, 2012 If I had an airlock would my heater get really hot in the car? Is the only sensor for the light in the expansion tank? Wasn't sure if there was another sensor anywhere. Quote Share this post Link to post Share on other sites