I bought an 04 g35 last year at a car auction with 70k on it and the engine overheated on me replaced it with a pre own engine with 50k on it and, its starting to overheat again. Temp gauge is almost at the danger line. Need help and ideas as to why its overheating?

 

The first and only step you did was replace the entire engine?

 

No i took it to Midas.. (big mistake) thought something was wrong with my coolant pump or housing and ask the guys there to check and see why my engine was overheating. After days in the shop they told me my engine gasket was cracked and they told me that to buy the part and labor would be a couple grand. He didn't recommend putting in a new gasket that would be working with used parts, but instead for a couple grand more I could have pre-own engine with 50k miles on it. That is what I ended up doing.

 

First off, 70k is pretty low mileage for a 04. This would be a bit early for a water pump as I have seen few replace their water pump prior to 120k miles; on the 50k motor, the likelihood of a bad water pump is even lower..

Also, not sure what they are referring to as an "engine gasket", possibly you meant to say "head gasket"?

If the head gasket was leaking, you would either see puddles of coolant under the car (gasket broke and coolant is leaking external), or alot of white smoke coming out the tailpipe (coolant is leaking internally, here the car would run poorly as well).

Were either of these symptoms?

One of the most common over-heating issues on our cars is related to how difficult it is to get all of the air out of the closed system when changing the coolant. This could cause unwanted air pockets to form and as a result push coolant out the overflow.

I would guess that this is the most likely culprit, or potentially a bad thermostat (maybe they reused the original one?).

The radiator could also be bad (this would be a common link to both installs), but normally when these go bad they leak. If blocked, then they will not operate as effectively, but the car will not overheat right away.

Why not take it to Infiniti and have them look at the issue ?

Here's a good tutorial on how the coolant systems works.

Good luck.

Mike

 

Thanks Mike,
My previous engine did leak some coolant that's why I thought the leak was coming from the hoses or housing and didn't want to do to further damage to my car. Midas was the closest place and thinking they could tell me what was wrong. The people there didn't have a clue what was wrong and had to hire a "specialist" to figure it out. Ya that is what they told me that i had cracked head gasket.
With this engine their is no leak but when i crank the a.c when I drive the temperature gauge rises to the danger zone i shut off the ac but the gauge stays where it's at. I'm going to take your advice and bring to an infiniti dealership.

 

Hopefully there is some type of limited warranty on the replacement engine? You may have to take it to Infiniti to get the problem diagnosed, then return it to Midas for the actual work. Or, Midas may just reimburse since they are for the most part a reputable shop.

 

wow midas doing engine swaps now?