I just purchased an 01 Teg GSR with an LS VTEC swap done to it. It has Skunk 2 manifold and throttle body, comptech short ram intake and header with an Apexi cat back exhaust. The problem I am having is that every time I get the car in traffic the temp rises to the point that if I don't pull over and let it cool down it will over heat. I checked the basics. The fans work, I replaced the thermostat, did a compression check and leak down test and everything was normal. But for some reason when in traffic the car gets hot and I lose coolant somewhere. No oil in coolant and no coolant in oil and no puddles under the car or steam. Thought sure it was a headgasket but after compression and leakdown test were good I am real confused. I can take the car out and romp on it hard as long as I am not in traffic its fine no matter how hard I run it but get in traffic and it heats up. Anyone have any ideas what is happening or what could be causing this???

 

Did you replace with an OEM TS? I had this problem before when I was running boost on my old car w/ an aftermarket TS. Car ran fine as long as wind was running through the radiator. As soon as you hit traffic, temp starts rising. I ended up buying an OEM TS and solved the problem.

 

As far as I know it is oem. I didn't do any of the work to the car and I got it from a dealer so he was clueless. But that still wouldn't explain where the coolant is dissapearing to.

 

Sorry wasn't thinking when you said TS I was thinking temp switch for the fans. Thermostat was from pep boys and was supposed to be an oe replacement.

 

Is the thermostat backwards? That would prevent it from opening.

 

No its not backwards. The thermostat does open because the car doesn't get hot when I'm not in traffic or when I leave it sit and idle. I let it idle for 2 hours and no problems whatsoever. I can got out and beat the snot out of it and red line every gear as long as I'm not in traffic its fine. As soon as I get in stop and go traffic it gets hot and it only seems to lose coolant when it gets hot but like I said previously compression test was good, leak down test was good and coolant system pressure test was good and it doesn't drip or leave a puddle anywhere. But somehow I lost 1/2 gallon of coolant in a 25 minute drive home.

 

OEM radiator?

make sure there are no hairline cracks on the top or bottom. at operating temp, if its open to atmosphere, the coolant can evaporate faster than you think.

 

Yeah that sounds like an evaporation issue if it's not leaking at all. I can't see how else you'd be losing it if your HG is fine. Triple check the Radiator, maybe try a new one or a new cap.

 

ok so on the way home from work today the car started missing but only while holding a constant speed or when deccelerating. Under hard acceleration it is fine. Any ideas??? Car is starting to make me second guess myself for getting it.