So for the last 7 to 8 months my tl has been sucking down the coolant and i cant figure out why. I recently had a cylidre misfire and i had to have à plug replaced i am dressing because of the résoir runnig low. What coule be happening?

 

I would look for a small/slow leak. If there is no leak you have a bigger issue. Have your coolant system pressure tested. It will help spot the leak.

 

Yep, ^:^ just as Fsttyms1 suggested !
Check the rad & cap, overflow reservoir, and all coolant hoses & connections for any signs of leakage. Does your exhaust puff white smoke ?

 

exhaust doesn't puff smoke, no water coming from the exhaust pipes either , and nothing in the way of a leak to MY eye, but I'm only an average DIY'er. I just got new struts/shocks, and a new oil pan... stripped my bolt last change... so all of that is going in to be done in a week or so. I'll have them do a pressure test as well. checked the radiator seal as well, and nada. car has 168K miles on it. did the water pump and belt change @ 100K if I remember correctly. had a misfire a few weeks back, so maybe the coolant is leaking into the oil? find it hard to believe though because I recently changed the oil, and there was no noticeable color change. from what I'm told if it's leaking into the oil it is clear as day when you change it.... milky is the description I've alway been given. any suggestions on what else I should do? would like to get another 5 years out of the car. normal driving, usually put 10-13K on it a year max. btw I change my tranny fluid EOD oil change, and I only use honda's fluid. also only use highmileage synthetic, and I usually seafoam the crank case on my drive home prior to my oil change. I do the exhaust sea foam as well, but that's every 20K or so. thoughts?

 

When ya say,sucking down the coolant...., just how frequently do ya need to top off the reservoir ?
A small pinhole leak is sometimes hard to detect, but once ya get the coolant system pressure checked....you'll know for sure !

 

hard to say how many times, frequently enough for me to notice... and way more than I ever have had to in the past.... which was pretty much never