I have the same model and issues with following experience.
Diagnose:
Simply remove your TS, radiator cap open, start your engine and stabilize the radiator water. Now notice any bubbles, if then collect some money to waste.
Coolant infrastructure:
Radiator, hose pipes, water body, heater pipes and its radiator, CNG hot water/coolant supply pipes etc...
Reason founded/learned: All the water/coolant infrastructure is now old, with new radiator installed, in my case hose pipes are not sustaining the pressure they expand like balloon at some points, heater/CNG pipes (a year old or more) got stiffed, and leakage started (ends and joints are not dry). Unless you replace all these with new (genuine stuff, which is not possible here in pk).
My experience:
- Car get heat up, my fault. Got fixed from Suzuki (two gaskets they installed, head facing etc done).
- After 7-8 months, Oil water mixed, engine stopped, don't know mechanic told a TIKKA inside damaged and leaked coz of aging factor.
- Well fixed (gasket, all TIKKAS, rings, valve seals), now one gasket (8 or .8mm thick i guess) according to mechanic, two gaskets are not good, one should be OK, now two years forget engine work, BUT don't install TS.
- Read on internet, TS is a must for engine.
- TS installed old one, temperature needle not stable, a new one installed, now OK.
- Noticed after TS, car power, engine stability, millage, heater etc...
- But coz of old infrastructure facing issues, filling water almost every day.
- Just after one year time comes to do the same stuff again :-(, car heated 2 times on mororway and lastly in normal drive inside city.
- Head gasket replaced by two thin (Japaneses according the mechanic).
- All fixed switched on, temperature was out of control.
- TS removed!!!! and fan on auto.
- After one month, Temp stable, water level is perfect.
- Compromises, car power, need to heat up car every time for minutes, no heater, millage is 2km/l less almost.
- That's all.
Conclusion:
This kind of issues with this car can't be fixed permanently (according to my experience).