Tank_EM2

Ive been having overheating issues overflow tank fills and then overflows block tested twice passed tail pipe is not steamed no visul leaks. Replaced rad cap and t stat with oem parts old t stat looked after market any one else having this issue

benchwarmer

Fans come on when it gets hot ? Is there heat when it gets hot ? There may be an air pocket , . Pull the heater hose behind the thermostat and immerse it in water then a piece of hose on the nipple and draw out fluid with a shop vac . Mine had one problem after another with getting hot now it's off the road because it's not reliable for long trips . I'll be doing a leak down test , compression test was o.k. but there's a sludge under the rad cap that's always been there and it drove many a mile without a problem . .

benchwarmer

Open the heater valve when you do that

Tank_EM2

Fans work vacuum bled yesterday no leaks got home and reservoir was almost full

benchwarmer

Maybe the cap is junk , I found an AC delco supplier I buy from , mostly for spite after buying some junk parts from nation wide brand name store . ie. a thermostat goes for under $5** , you can't get a sandwich for $5** how can you expect a $5** part to perform well .

Tank_EM2

Thermostat and cap are both oem

civichxtreme2

Could the t stat been installed backward by mistake, you might laugh, but Ive seen it

Tank_EM2

Update since installing t-stat. Reservior has not filled like before but i suspect a internally clogged radiator might be the culprit. Driving home from work (commute is 37 miles one way) on hwy needle crept slowly turned A/C off turned on heater needle didnt climb after that was about 10 min from home at this point will install new radiator either friday or Saturday

Tim1959

--------------
"having overheating issues overflow tank fills and then overflows"
This is a CLEAR indicator of a blown head gasket and/or warped cylinder head.
These engines are NOTORIOUS for head gasket failures!
All it takes with these cars is running the engine while overheating - even for only a few minutes.

benchwarmer

I would check the flow rate on that radiator before replacing it , I know hey don't give them away for free , you may spend time and money and still have the same problem . Unless that's what you're into . All I did with mine is pull the lower rad. hose and put a large pan under it , then timed how long it took to fill it with a hose and checked that against running it through the rad. cap through the rd and into the pan . If it's truly clogged it will take longer to fill the pan .

Tank_EM2

Block tested twice and no combustion gasses in coolant when needle started climbing turned A/C off and heater max needle went back down needle and overflow have been normal since

Tim1959

-------
On these cars sometimes cooling system leaks and diagnosis can be tricky.
Sometimes the cooling systems on these cars leak intermittently, like only when the engine is under heavy loads.
I would give the car a good test drive on a flat road with a wide-open throttle (at least once) with a warm engine.
A completely sealed head gasket should not leak at all under these operating conditions.

Tank_EM2

Update replaced Rad on friday 8/30 car sat all weekend drove to work and back yesterday and today. Got with in 10 min from home on off ramp needle began to climb turned heater off needle goes back down car takes 2 days of commuting to start acting up.

Tim1959

-------
If the temp gage shows overheating at any time, you must find out what is causing the overheating, or risk serious engine damage.
A very common cause of overheating is low coolant level.
If you have a low coolant level you must find the leak which could be external (leaking hose) or internal (blown head gasket).