Four problems related to engine overheat have been reported for the 2003 Toyota Highlander. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2003 Toyota Highlander based on all problems reported for the 2003 Highlander.
The engine overheated suddenly, blowing hot air from the ac and the temperature gauge went up. We managed to get home and get to the Toyota dealership the next day. The dealership mechanic told us the engine bolts stripped due to the block being soft, and that he had seen this problem before. The issue of the soft block was confirmed in a subsequent search of the internet. Apparently Toyota is aware of this flaw, but there is no warranty remedy. The 2003 inline 4-cylinder engine is the model with the bolt stripping problem. Neither the dealership nor another japanese auto repair place would consider trying to replace the bolts. They said that because of the soft metal in the block, a new set of larger bored bolts would be unlikely to hold. The cost to put in another engine is approximately the value of the car, if there were used engines available. A new engine would be in the $15k range, much more than the car is worth. We will likely sell the car for scrap. When we bought the car, we felt we could reasonably expect a 250k mileage life. The engine failed at 128k. Just half of its useful life.
The contact owns a 2003 Toyota Highlander. The contact stated that the temperature gauge indicated that the engine overheated. The vehicle was taken to the dealer where the failure was located at the head gasket. In addition, the dealer advised the contact that the engine bolts were stripped. The vehicle was repaired. The dealer replaced the head gasket and the bolts thread. The manufacturer was made aware of the failure. The failure and the current mileage was 145,000.
2003 Toyota Highlander has head bolts stripped from block, causing fluid to slowly leak from engine and overheat. First symptom is ac blows hot air. Most folks who experience this burn up the engine, but I was fortunate and was able to have it repaired at a cost of $2750. 00 !!!!! this is a clear defect, head bolts do not simply get stripped from a block.
Engine overheated. Service dept diagnosed bad head gasket. Discovered stripped threads in the block for two rear head bolts. Service dept attempted repair with rethreaded helicoil but would not hold. Engine replacement is required.