University of YouTube

The check-engine light on my daughter's Jeep Cherokee came on and so I had her use my OBD2 reader to pull the code from the computer. Sometimes the code is a $2000 problem and other times it is a $20 one. She checked the code and found it to be closer to $20 than $2000. The code she pulled is P0128 which indicates that the engine never gets up to the proper operating temperature. Generally this means the thermostat needs to be replaced.

There are a number of tests to verify the problem. If the car is overheating or running cold, that is a good indicator the thermostat is bad. In my daughter's case it is running cold, which means that the thermostat has failed in the open position, which is what it is engineered to do. The final test is to feel the hoses going to and from the engine. If they are both cold, then it is not a temperature sensor problem. My daughter ran through the diagnostic and we are sure the thermostat needs to be replaced.

Now we have two options. We can take the car to a trusted mechanic and pay $300 to have them replace the part or we can buy the part from the auto store and do the work ourselves. Like most of us, my daughter is not made of money and would prefer to save $250 and do the work ourselves. Thermostats generally run about $10 but the Jeep Cherokee requires one to replace the entire thermostat housing at a cost of around $50. It is $42 if you buy an aftermarket part or $63 if you buy the original part from the dealership. At such a low cost differential, I suggested my daughter use an original part.

This evening I spent some time going through YouTube videos on how to pull off the old part and replace the new one. Unfortunately Jeep did a very poor job of making the repair easy. You have to remove a number of different pieces and have useful socket-set attachments, all of which I have. After reviewing the videos, I know it will take a couple of hours but is not an overwhelmingly difficult job. The trick will be to remove as many parts as possible and being able to work hands into cramped spaces.

One nice thing about YouTube is there are a number of do-it-yourself auto mechanics willing to show you the steps for engine repair. They will also show you various tips and tricks to help make the job easier. If you review the videos and feel the job is beyond your skill set, then feel free to back away and leave it to qualified professionals.