Madscientist reserch

2002 T/A has stock short block w/ heads,cam, intake done. Car's temp gauge reads 215 constantly after warm up, no matter what. Decided to change thermostat from 180 to 160. After changing fans to on at 180 & off at 165, I noticed hp tuners said temp was running at 230. Checked temp with temp probe & ir gun & both said 220. I cant figure out why car runs hotter now then before?? Checked system with pressure checker and will gradually creep down to 9 psi & hold there? Whats weird is system will not build any pressure while running or hot. I can take rad cap off with no pressure at all. Figured bad or leaking head gasket, but tests proved that wrong. Tests done :

Pressure test - holds 9 psi?
Leak down test on cylinders - worst one leaked 12%
Hydrocarbon test of water - passed
No water in oil - sent for lab test(reg results)
Radiator cleaned & tested
New rad cap
Fans spinning - dont seem to be pulling large amounts of air. Can they be tested? Slow down or go bad?
Any advice would be greatly appreciated!

quickbrick

iTrader: (5)

Check all hoses for collapsing while running. Is the stock waterpump still on? Why did you only pressurize it to 9lbs. I would replace hoses and use sealer on the insides where they connect. Did you run it till it got really warmed up checking water level? My post isn't exactly organized, but by going over these things you should be able to figure out the problem.

Madscientist reserch

Yeah, I replaced hoses, didn't put sealer on them. Stock water pump. Jacked front of car as high as I could & ran 2 bleed air. Water level full at temp, all the way through temp range

Madscientist reserch

Also put 18 - 20 psi of pressure & it gradually leaks down to 9 psi where it holds.

01ssreda4

iTrader: (96)

Why are you so concerned about 230 degrees? That's normal operating temp for these engines.

quickbrick

iTrader: (5)

My engine runs at 180, even in 95 degree weather. I monitor my with a scan gauge, so it displays what the pcm is seeing. If it's bleeding to 9lbs there is a pressure loss somewhere. How many miles are on this waterpump? You should not need to jack the car as the radiator fill/cap is the highest point in the cooling system. This may sound like an insult but have you check in front of the radiator and inspected the natural air path? Are all the factory plastic panels in place?

myk

iTrader: (4)

Keep in mind that the gauge isn't accurate-most refer to it as a dummy gauge. As for running @ 230, I'm pretty sure that's normal operating 'temp for these guys...

Madscientist reserch

I want to get the engine to run around 175 or 180 as that is where it made most power on my engine dyno. I understand that gm had them at a range of 210 to 230, but engine lost 22 hp there. I also have engine tuned at the 175 temp. After reading a few posts on here about guys actually running cold, I figured 175 would be not an issue. It is the stock water pump, but was on dyno with no problem. Unless it went bad since then coincidentally Yes, I did check plastics up in front of rad, only thing I found was one of the push pins was gone, but replaced it.

joecar

This is a problem, you have a leak (internal or external).

joecar

See if you can bleed more air by undoing the hose from the crossover steam tube.