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Overheating after FMIC install with AC on

2824 Views 29 Replies 3 Participants Last post by  JibbelSandwich
I recently installed a Mishimoto Race Intercooler, FIC 525cc injectors and the Sideways Guru radiator block off plate. After installing just the injectors and fmic, I was getting above 215F driving on the freeway with the AC on. I thought it was because the block off plate wasn't installed.

After installing the plate and flushing my coolant along with a new thermostat and hoses, the car seemed to be fine. It wasn't hot enough for AC so I never ran it but idle was fine, right at 183F, and driving would be between 179 and 188 depending on if I was wot or going up a hill. I also run a 60/40 ratio.

Today it was hotter, in the mid 80s, and on the freeway with the AC on, the car started going up towards 215F. I shut off the AC and it would start to go back down. If I was cruising and not accelerating, I was able to turn the AC back on. It was still high, maybe around 195 but if I didn't accelerate, it wouldn't rise. Coasting also helped. I was never able to cruise or accelerate and have it stay at 183 even with the AC off. It didn't really matter what speed either.

When I drove later when it was cooler, around 65F, I didn't go above 186F no matter how I was driving. This was with the AC off though. I checked the coolant level and it seemed fine. Not sure how to go about diagnosing this.
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I've gone through 4 thermostats over the years. The original one, two OE replacements and one Motorad which I currently have. Only the original and the Motorad run at 180F like they should. Both Hyundai replacement ones I got ran at 185-187F.
I have gone through 0
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What temp does it run normally?
I have never looked at it I will have to add that on the torque app display when I drive it later.
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