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Have a weird issue, if I'm super easy on the car (driving mrs daisy) it's fine, but if I'm driving normal flow of traffic speed and/or interstate my coolant level drops and I have to add some about every week or so. New radiator, new hoses, inspected heater core it looks and acts fine not leaking that I can tell not getting any coolant in oil.
Where do you think it's going?
Had a shop also look and he couldn't find any leaks said to be safe best replace all seals $1000 , is that correct price and what is "all"seals he may be referring to
Thank you

 
Rep Power: 211

Well, hopefully not into the cylinders via a head gasket leak. Did the shop do any testing (leak-down test) to rule out a breached head gasket?

Any wetness near floor boards...leaking heater core?

Take it to another mechanic for a second opinion.

 
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Sorry for late reply. I'm not sure what test they did, if any.
Nothing in floorboard and still have good heat in car, my father-in-law drives the car to work and back ~5miles/day.

Another related question, had new radiator put in and drove it on a small 35 mile trip. Car sat in garage from Monday-Sat. and as I was un doing the radiator cap pretty much blew the cap out of my hand and sprayed coolant everywhere, is it normal to have that kind of pressure after sitting not running for 5 days?

Thanks

 
Rep Power: 211

That is not normal and the cooling system should not remain under pressure that long.Below are some steps to consider taking:

1) remove the coolant reservoir and the hose from the radiator to the coolant reservoir. Blow air into that hose and make sure it isn't clogged.Replace if needed. Also, clean the reservoir with a brush and degreaser...especially the nipple where the hose attached to at the bottom to ensure proper flow.

2) bleed air from the coolant by:
a) raise the front end on jackstands as high as possible
b) turn climate control to Max heat and fan off
c) remove radiator cap and reservoir cap run engine at idle for 20-30 minutes and fill radiator and reservoir as needed with (50/50) coolant mix as needed.
d) low engine to cool fully and then check coolant levels in reservoir and radiator..too up as needed.

3) Rent a block tester and buy block tester fluid ($10) at Auto parts store. Do a block test on it (search YouTube) to see if exhaust gases are getting into the coolant system via a headgasket breach.

If block test is positive then head gasket needs replacing. If block test is negative a "leak-down" (injecting air into cylinders at TDC with radiator cap removed/watch for bubbles) test is still require to rule out a headgasket breach.

 
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Thank you much. I should have some free time this week and will check things out, I'll do my best to update asap

 
Rep Power: 211

remove the spark plugs and see what they look like,

you might be "burning" the coolant

if coolant is leaking into the cylinder and being "burned" the plug or plugs will look grey and possibly wet

 
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Update: engine started dripping oil, being that I'm only off on some weekends(on-call most) and F.I.L not too sure about working on cars it ended up being taken to a "mechanic", long story short they had issues had to send engine off to be honed and checked now almost month later it's running but waiting on a new crank case sensor to get shipped as it started throwing codes,
Thank you for any and all suggestions on what to try/check