Honda City 1.3 manual Heating up

[adil.mumtaz98]

Salam everyone! I have a 2010 Honda city 1.3 manual. From past few weeks I'm having heatup problem. The car runs fine on normal roads but problem occurs when stuck in traffic (low gears for long time) or in uphill roads. Its running on guard coolant. The heat up sign comes up and when I park the car in idle for 2-3 mins, it goes. What I observed is that car is throwing all coolant from radiator to reservoir bottle resulting in overflowing of bottle along with bubbling in bottle. Fans are working fine normally but when car gets heated up, there is little delay in starting of fans. I checked for thermostat but its working fine. Cannot confirm about the radiator cap but it seems fine. A possible cause could be head gasket leak but there is no such symptoms. Like no white smoke, no milky oil and no coolant loss. What could be the probable reason ? Im really confused. Kindly help and guide

[farooqk80]

Did you cut the concentrate with water?

[Djaymx]

Car temp should not go above 92-94C if you can hook it to a OBD2 reader and get temperature readings that could tell you a lot.

Remove the thermostat and if the problem is solved then it is just a blocked thermostat valve

If there is no coolant loss it means the bubbles could be from a minor leak in head gasket (exhaust side) - sometimes the leak is just so minor that it can be hard to detect.

I would do a citric acid flush and run it with distilled water for a few days just to clear up any rusting and blockage.

Guard coolant is most likely just colored distilled water, better than nothing but still not worse than tap water.

You need to take it to a reputed workshop with a radiator service machine at the very least.

After 13 years of service it is also possible the water pump is gone bad and isn't circulating properly so the stagnated coolant boils over and over again until steam reaches the reservoir and condenses back.

In that case you will need to replace the water pump only.

[Massive_One]

What I observed is that car is throwing all coolant from radiator to reservoir bottle resulting in overflowing of bottle along with bubbling in bottle.

This is a typical sign of bad radiator cap. change it. the radiator cap is not able to hold the pressure inside radiator and when pressure builds up and coolant gets hot, it lets it flow to the reservoir tank immediately.

[Massive_One]

The car runs fine on normal roads but problem occurs when stuck in traffic (low gears for long time) or in uphill roads.

are you sure thermostat valve, radiator and fans are running fine ?

usually this happens when thermostat valve is not allowing enough coolant to pass through radiator to get cooled down by the cooling fan.

so step 1 is to change radiator cap.
step 2 remove thermostat and observe
and also get radiator services if you haven't done already.

also as Djamyx said, check car's temp. through computer , what temp. the fans are turning on and is it supplying enough current for fans to run on full speed, etc. you'l get to know a lot through these readings.

[adil.mumtaz98]

Yeah, already removed the thermostat, its still getting hot if driven on low gears for while. Points taken.Thanks

[adil.mumtaz98]

I doubt the same, I checked the cap for any air leak or broken seals but it looks fine. Any other authentic way of checking the radiator cap ?

[adil.mumtaz98]

Yeah I checked for thermostat by placing it in boiled water. Its working fine. Points taken .Thanks

[adil.mumtaz98]

Sorry what ?

[pwuser162557941033]

You can buy coolant as concentrate, which requires mixing with distilled water before you pour it into the system, or as pre-mix, which contains a (usually 50%) mixture of distilled water and coolant.

Does the Guard coolant bottle say whether it's pre-mixed or a concentrate? Knowing Guard's products, I doubt it.

Concentrate alone has a very poor ability to move heat out of the system, the water is responsible for that job.

Like everyone else has said, check your:

• Radiator cap
• Coolant lines
• Thermostat
• Radiator fans
• OBD2 data (fans, temperatures)
• Radiator
• Water pump

[arslan.v8]

You have a choked radiator.

[abid110]

I doubt the same, I checked the cap for any air leak or broken seals but it looks fine. Any other authentic way of checking the radiator cap ?

City must be using a 1.1 rating radiator cap. this is a rare item to find in market and any auto shop you go will definitely give you a 0.9 rating radiator cap. first check which radiator cap you are currently having. its not an expensive item, buy another one and check its performance - auto stores keep used caps as new ones are not readily available. have faces this issue many times when i kept liana

[Massive_One]

when you get the issue sorted out, do let us know what was the culprit. It will help others for the future.
best of luck !

[farooqk80]

I have a can of guards coolant laying around. It clearly says concentrate in CAPS

[adil.mumtaz98]

If its a choked radiator or faulty water pump. Why not its heating up on normal travelling even if I drive in for 2,3 hours. No problem what so ever
Only getting issue when stuck in harsh traffic or uphill roads.

[Massive_One]

If its a choked radiator or faulty water pump. Why not its heating up on normal travelling even if I drive in for 2,3 hours. No problem what so everOnly getting issue when stuck in harsh traffic or uphill roads.

so, the water pump blades spin at more speed when the car is moving at higher RPMs, and there is additional air crossing through the condenser fins as well when the car is moving, hence it performs well when the car is moving.

[Djaymx]

Sometimes the condenser and radiator both have dirt and road debris on it which can reduce heat exchange greatly, so at lower speeds the air simply cannot flow through the fins.

Put a torch on the back side of the radiator and see if you can see the light up the front.

The bubbles in coolant overflow tank indicate bad water pump or clogged/choked coolant lines inside the engine.

Or both issues could be possible at the same time.
Do a coolant flush (run liqui moly radiator cleaner) for a few hours or just put citric acid and clean water in it and see if rust and calcium build up is an issue.

[arslan.v8]

Because the radiator isn't getting enough airflow at city speeds to cool it sufficiently. Hit the highway, drive at 40kmph, and I guarantee you it would heat up. If it was working fine and not choked, it would perform fine at any speed.

Also, a water pump only goes bad when it leaks or is gummed up and eventually jams. If it's spinning, it's doing it's job. It's not a complicated part.

[adil.mumtaz98]

What do you suggest then ?

[arslan.v8]

I would suggest you to take it to a professional for diagnosis. If I was in your shoes, I would start with a new radiator, new t-stat valve and any new coolant lines that are weak. I don't know your car's history so I'm not sure if your engine has ever heated up enough to damage the head gasket. There are usually tell tale signs for a head gasket failure.