Originally Posted by veedubmechanic
Have you replaced the coolant temp sensor on the coolant hose by the driver side of the cylinder head?
A year ago, my wife's 99 Beetle (with only 34k miles) overheated going into the city of Lake Havasu, AZ.
We removed the thermostst housing ourselves as it got so hot it cracked and was leaking. We repaired it with JB and reinstalled it without the thermostat hoping this would allow us to return home OK.
No such luck. We ended up taking it to a local repair facility there. In addition to the theromstat & housing issue, they found the [plastic] water pump was completely destroyed.
The system was backflushed, radiator pressure-checked, a new thermostat & housing and a (metal vane) pump were installed along with the required VW coolant. Afterwards, the car would idle for hours without overheating, but would overheat after driving only 5 ~ 10 miles.
A So Cal VW dealership service manager told us to bring it in as is was still under the 100k drive-train warranty, so we trailered it there. A week later, the dealer informed us that the warranty was void due to a substance called stop-leak being introduced into the cooling system. They said the tell-tale sign was a gray powder substance coating the insides of the cooling system components.
Interesting to note, we had noticed a gray powder residue on the interior of the thermostst housing and coolant hoses prior to leaving it with the repair facility in Havasu, so the problem with the stop-leak substance had to have occurred prior to the inital overheating problem in Havasu.
We just started to look into repairing the problem again a week ago. There is a smell of coolant and steam emitting from the tail-pipe, so it looks like the head gasket is gone.
My wife had always had the car serviced at 'Certified' VW dealers since she bought the car brand new, so we question 'How could this happen to a new car?'
Could someone at a VW dealership have punctured the radiator while replacing a foglight on the car? ... then put stop-leak in to cover up their neglegence instead of replacing the radiator?
The reason I ask is that one dealership said they had to disassemble the entire front of the car to replace a broken foglight. When we received the car back, they had broken the right headlight housing and forgot? to reinstall the hood release mechanism. Poor workmanship is the only logical reasoning I can think of as to how any cooling system damage could have occurred.
Also, after reading similar cooling issues on this forum, was there a recall for the plastic vane water pumps? We don't see anything relating to a recall for a water pump in my wife's documentation on the car ...