- Hello so ive got a convoluted issue. The background is I started my car Thursday the 7th of November at about 9am and I heard dripping. I initially thought nothing of it but when I backed out there was a huge puddle. It was green coolant so I looked and the car was not overheating, that is until about 30 min later it started rising, and boiling coolant was dripping onto the ground. Long story short I took it to a highly rated shop in the area was told it was the intercooler hose, and was quoted 460$. The kicker is they did the work before getting Authorization from me, so I ended up refusing to pay and they lowered it to 170$. I picked up the car and let it run 15 min, and it does not overheat. I drove it down the road then stoped and checked same thing right in the middle. So I attempted to go to a further destination about 4 miles, and stoped paying attention to the temp gauge. When I looked back at it it's right below the top bar so I shut the car off then pulled over. It cooled back down rather quick but I towed it anyway to be sure back to the shop I originally brought it to, I told them it was still overheating. Mind you they claimed they tested it pressure tested and verified the head gasket was good when I first brought it to them. So upon bringing it back they just say they "think" it's the thermostat with basically no testing, and quote me about 500$ to replace it with 300$ish from the part? I've never seen a thermostat cost that much, I feel they were trying to get over on me since I did not pay them the initial amount the first time I went. Tldr I picked up the car rejected the work and drove it home did not overheat. So I drove it a bit more then it did start to creep up. I discovered that the heat works off and on, basically if I rev the car above 4k RPM the temps drop. If I keep the car at low revs no heat and it overheats. But if I rev the car than it will produce heat and not overheat. I dont have to rev it constantly but regularly I'll put it in manual, and drop a couple gears to get the temp back down once it starts to creep. Anyway that's very over explained but if anyone has thoughts please shoot them my way. I think I included everything but if I did not just ask for missing details. I am no mechanic but I do dabble I'm DIY and if the thermostat is the issue and easily accessible, I would like to try at it myself. I could only find guides for the G35 but they have the same engine so I'm not sure. Also there is NO history of overheating with this vechicle at all. This all just started. I also did see there was a recall for the cooling fans perhaps there faulty? My friend suggested that since when I rev it it cools down, perhaps It's related to the water pump since it's belt driven? Fast engine=pump work? Not sure, maybe clogged heater core? Or they didint bleed the system of air correctly? They did replace the radiator cap without me asking, perhaps that introduced air into the system? Anyway I'm done guessing I can't afford to pay someone just yet to look at it, but while I wait/before I do I wanted others opinions, thanks.
See the troubleshooting section of the site FAQ for tips on diagnosing an overheating condition.
@chucktobias Okay ill take a look, do you have any thoughts personally?
Frankly I can't work my way through and digest that dense block of text that was initially posted. (Bear in mind that a clear and concise description of a problem yields the best answers.) However the information in the FAQ is a good starting point when dealing with overheating problems.
@chucktobias Ah I see I thought the more details the better, sorry. I guess the main question was doing the reving to cool down sound thermostat related.
Details are good, they're needed. However in this case the form they are in currently is a bit tough to get through. Paragraph breaks and/or bullet points can help make the text a lot more readable.
Thermostats can be tested by seeing if they open up in a container of water heated to their temperature rating. However if you still have the 19-year-old original unit in there replacing it would be a good idea. If you do that be sure to use an OEM thermostat, or at least one from the OEM supplier.
@chucktobias Got it, I'll look into testing it. Thanks.
175k miles clean title no accidents 2 owner vechicle. Dealer maintained by first owner. Was not beaten as far as I'm aware.
Also the overflow tank is full of coolant.
And the fans sound like there running have not tested further.
Also it seems unrelated to the speed I'm at reving it while parked works as well as reving it while moving.
Also I did a couple times get a bad smell from the heat, but I didn't really smell it outside the car. It kinda went away though.