This is now my third thread related to fixing a leak in my 04 Disco coolant system. I found a small leak in the heater hose that comes out of the heater matrix. I replaced the pair of hoses yesterday but then I lost the bleed screw while I was flushing the sytem (I found it this morning).

So today I attempted to bleed the coolant system following the handy instructions posted as a sticky. Everything was going fine and as heat started to come out of the vents--all the sudden the temp gauge went crazy and dropped all the way to cold and the warning light came on.

I immediately shut off the engine after I replaced the cap on coolant resovoir. I waited a few minutes and restarted the engine. The temp needle went all the way to hot and then dropped right away back to all the way cold and the warning light came on. Also, the engine was knocking and not running correctly at all.

So, at this point should I cave and have it towed to a mechanic? I'm going to wait for the truck to cool down and see what happens, but I was wondering if anyone had experienced this in the past or had any other advice.

Thanks from a frustrated owner...

 

It is dropping to cold because there isn't any coolant on the sensor. You aren't bleeding it properly.

 

I would say if its running bad then its not a bad coolant temp sensor I would think!
Do you have a OBDll Meter that tells the real temp of coolant?
Double check every thing you did maby something is loose!

 

I took another look at everything last night after the engine cooled back down. All the hoses were secured, so I drove it around the block a few times. Once it got to operating temp, the light did go off and the temp gague went to its normal location. No issues this morning on the drive into work this am. I'll just keep a close look on the coolant level for the next several days.

Thanks for the advice.

 

If you want this fixed this morning, send me your number and I'll call you right back.