Car Heating Up While A/c Is On

[nazly]

I had issues with the A/C on my March K11 and when I took it to a A/C Repair spot, there were leaks on the Cooler and replaced it.

Everything was fine for like two weeks unti the A/C was switching on and off randomly. I took the car there again to realize a fualty cutout. They replaced that as well. (Not the same cutout type, but different one).

Now while A/C is on, the heat gauge is going up. It doesn't seem to rise if I run without A/C (atleast for now). At the time of heating with A/C, both fans are on. If I switch off the A/C and keep the engine running idle, the radiator fan still runs and brings the heat gauge down.

What could be the issue? I'm not an expert, but with my knowledge with this car, nothing else could cause this heating up issue. (Radiator etc..)

Would like some hints coz last time I had heating issues, the garage guy took me on ride by replacing a lot of things while the issue was on the fan. Now I try to figure out where the problem myself and ask them to fix it.. Any geniune place where I could diagnose this problem?

[maheshw]

hello..

i had a issue which similar to your issue.chk the below link.

http://forum.autolanka.com/topic/15394-temperature-increase-in-fb14/

in simple terms issue ws in a radiator fan relay. its mulfunctioning. it wil works only when the temparatures reaches more 80%. after replace that issue was ok. just condult a good electrician.

[nazly]

Thanks. Thats something I will look into. My gut feeling was that its something to do with an electrical component than radiator or something. This a perfect start.

Just curious though, in mine like I said above, if I switch off the A/C, the radiator fan switches on automatically when the temprature rises. Both fans work when A/C is on.

Didn't come across an occassion where the fans were not working when its supposed to.

Again. Thanks for the heads up. Will look into that.

[maheshw]

but anw u just check whther your both fans are working when ac on & temparature high. if so it can be either blocked radiator.

[Charith H Jayasinghe]

I'm not an expert but interpreting your symptoms,

(Your fans working with or without AC but with AC on heat goes up. Few weeks back you had cooler leaking issue an AC faulty cut out issues.)

When did you change your coolent and flush your radiator last? Did you check for other suggestions mentioned in shared link by Mahesh.? I feel it is due to blocked (partially) radiator core.

Edited October 1, 2013 by Charith H Jayasinghe

[nazly]

I took it to the Electrician and with after thouroughly checking and fans working as they are expected, he was saying there doesn't seem to be anything wrong with the fans or electornic components.

There were oil leaks and stuff which I repaired like a couple of months back. During that time the garage guys replaced the waterpump. So if I'm correct they had to pull the coolant out and refilled the same thing back into it. I didn't do a proper flush or anything like that. It's moslty water now. Since the heating issue popped up after the A/C repairs and ONLY when the A/C is on, I assumed its something to do with the A/C.

I do daily runs between Wattala and Bamba. Coming from Wattala with A/C on, heat gauge rises above normal level when I get to Maradana. I drove home yeserday without A/C, in moderate traffic, heat didn't rise at all. Curious..

Should I try with the flush?

Edited October 1, 2013 by nazly

[monty]

Had a similar issue in two different cars. Ended up been a faulty thermostat in one and a burnt fuse controlling the fan in the other.

[Charith H Jayasinghe]

Let's wait for senior comments. Meanwhile, when did you replaced the water pump? and why?. What do you mean by " it mostly water now" in above comment?

If it's water then it might support my conclusion - partially blocked radiator with normal water (relatively low heat capacity) lead to under performing radiator.

[Rumesh88]

Let's be a bit more objective instead of saying "normal" "going up" "going down" etc.

1. When you say the temperature is "normal" do you mean the half mark on the gauge?

2. When you cold start your engine (radiator fan off), how long would you drive (without AC) before the gauge comes to half mark (or radiator fan kicks in)? (5min? 1km?)

3. When you get to Maradana is the gauge crossing the upper limit or is it just above the half mark?

4. What was the problem with your water pump? Was the impeller worn out or bearing leaky?

5. When you check your coolant level in the morning is it always full or do you see a small level drop (1 or 2 cms)?

[nazly]

Let's wait for senior comments. Meanwhile, when did you replaced the water pump? and why?. What do you mean by " it mostly water now" in above comment? If it's water then it might support my conclusion - partially blocked radiator with normal water (relatively low heat capacity) lead to under performing radiator.

Water pump was replaced like a month back during an oil leak repair. I was told it should be replaced.

I had heating issues sometime back and the coolant overflew. The radiator fan was the culprit and replaced. Filled water and didn't fill coolant after that. I was waiting till all these repairs out of the way.

Let's be a bit more objective instead of saying "normal" "going up" "going down" etc.

1. When you say the temperature is "normal" do you mean the half mark on the gauge?

2. When you cold start your engine (radiator fan off), how long would you drive (without AC) before the gauge comes to half mark (or radiator fan kicks in)? (5min? 1km?)

3. When you get to Maradana is the gauge crossing the upper limit or is it just above the half mark?

4. What was the problem with your water pump? Was the impeller worn out or bearing leaky?

5. When you check your coolant level in the morning is it always full or do you see a small level drop (1 or 2 cms)?

1. Yes

2. Yeah, something like that. More than 2kms I assume.

3. around Maradana it starts rising above halfmark and reaches like 90% by the time I hit Bamba. One thing I noted, coolant/water doesn't overflow or get reduced after checking later.

4. I think it was worn out.

5. Yes. It's FULL.

Thanks for the concern guys. I just want to figure this out. I kinda have lost faith in ppl I know. Even would appreciate a right place where I could check all these than say replace this and that without diagnosing what the problem is.

[Rumesh88]

Your heating issue seems to be somewhat marginal and it may be difficult for the mechanics to find an exact cause. Since you had a history on the same issue and replaced a few things (like water pump, fan motor etc) there are several possibilities.

1. Partially clogged radiator. If your water pump impeller was worn out that means there had been rust forming inside and a part of it may have ended up in the radiator.

2. Replacement water pump or the radiator fan being inefficient if they are not original/genuine parts.

3. If any part of the radiator shrouding was removed or modified during repairs thus changing the air flow.

If you can get the radiator removed and flush with water in the reverse direction you can look for the loose rust particles. If you exclude 2 and 3 above, get the radiator cleaned for it is the most logical thing to do.

[Charith H Jayasinghe]

Nazly, I Agree with Rumesh as he is thorough in this field. Then you need a radiator flush. You could do it at that time itself. Better change coolent every yearly and it seems you haven't done so.

[Komisiripala]

Can I suggest a simple remedy, one that may have easily been overlooked:

Go to a car wash place and get them to hose off your condenser properly. Sometimes dust build up on that can cause overheating. This happened in the datto. I know I know sounds silly but it really did happen. It's not gonna cost you anything. Just try. And inefficient condenser will cause the compressor to over exert itself and then cause to a bigger load on the engine. Which will cause it to overheat.

[maheshw]

Can I suggest a simple remedy, one that may have easily been overlooked:

Go to a car wash place and get them to hose off your condenser properly. Sometimes dust build up on that can cause overheating. This happened in the datto. I know I know sounds silly but it really did happen. It's not gonna cost you anything. Just try. And inefficient condenser will cause the compressor to over exert itself and then cause to a bigger load on the engine. Which will cause it to overheat.

and this is am doing once a month. really true comi

[nazly]

Your heating issue seems to be somewhat marginal and it may be difficult for the mechanics to find an exact cause. Since you had a history on the same issue and replaced a few things (like water pump, fan motor etc) there are several possibilities.

1. Partially clogged radiator. If your water pump impeller was worn out that means there had been rust forming inside and a part of it may have ended up in the radiator.

2. Replacement water pump or the radiator fan being inefficient if they are not original/genuine parts.

3. If any part of the radiator shrouding was removed or modified during repairs thus changing the air flow.

If you can get the radiator removed and flush with water in the reverse direction you can look for the loose rust particles. If you exclude 2 and 3 above, get the radiator cleaned for it is the most logical thing to do.

I saw your reply last evening and went to a Radiator service spot today morning but since it will take like couple of hours and I badly needed the car with me, I'm planning to do this over the weekend. Running without A/C at the moment. Thanks.

Nazly, I Agree with Rumesh as he is thorough in this field. Then you need a radiator flush. You could do it at that time itself. Better change coolent every yearly and it seems you haven't done so.

Great. Yes, should do that as well. Thanks.

Can I suggest a simple remedy, one that may have easily been overlooked:

Go to a car wash place and get them to hose off your condenser properly. Sometimes dust build up on that can cause overheating. This happened in the datto. I know I know sounds silly but it really did happen. It's not gonna cost you anything. Just try. And inefficient condenser will cause the compressor to over exert itself and then cause to a bigger load on the engine. Which will cause it to overheat.

Interesting. So I will try this today before flushing and servicing the radiator which I planned to do over the weekend. Thanks.

[nazly]

Your heating issue seems to be somewhat marginal and it may be difficult for the mechanics to find an exact cause. Since you had a history on the same issue and replaced a few things (like water pump, fan motor etc) there are several possibilities.

1. Partially clogged radiator. If your water pump impeller was worn out that means there had been rust forming inside and a part of it may have ended up in the radiator.

2. Replacement water pump or the radiator fan being inefficient if they are not original/genuine parts.

3. If any part of the radiator shrouding was removed or modified during repairs thus changing the air flow.

If you can get the radiator removed and flush with water in the reverse direction you can look for the loose rust particles. If you exclude 2 and 3 above, get the radiator cleaned for it is the most logical thing to do.

So I did this on Saturday. Radiator was removed and flushed. Added new coolant. Well, I have good news and bad news.

The good news is the heat level is at the usual half way mark when I did few average long runs.

The bad news is not always, last evening the traffic was terrible and after like a one hour drive on traffic I found the heat level rising above the half way mark and going up till about 75%. I noticed its coming down and going up within 50%-75% for sometime until I had reached home.

Any clue? All the above instances I had A/C ON.

[maheshw]

during that 50%-75% heat rising time did you check whther the both fans are on in HI speed ?

[nazly]

Not yesterday. But during the heating up issue prior to the radiator fix I checked and I assume it does. Nothing out of the ordinary.

How does the thermostat come into play? Can it cause this situation.

When I bought the car about 3 yrs back, it didn't have one. I installed a new one like 2.5 yrs back..

[Rumesh88]

Not yesterday. But during the heating up issue prior to the radiator fix I checked and I assume it does. Nothing out of the ordinary.

How does the thermostat come into play? Can it cause this situation.

When I bought the car about 3 yrs back, it didn't have one. I installed a new one like 2.5 yrs back..

That means there must have been a heating issue even before you bought the car and someone must have removed the original thermostat as a remedy. When you cleaned the radiator did you observe any loose particles (like rust, debris?).

Thermostats are very reliable and on their own would not cause over-heating except in a very rare case. As I said before your issue is marginal. Are you sure that your radiator shrouding is in its original condition? Better if you can compare with another car of the same model.

[MkX]

So I did this on Saturday. Radiator was removed and flushed. Added new coolant. Well, I have good news and bad news.

The good news is the heat level is at the usual half way mark when I did few average long runs.

The bad news is not always, last evening the traffic was terrible and after like a one hour drive on traffic I found the heat level rising above the half way mark and going up till about 75%. I noticed its coming down and going up within 50%-75% for sometime until I had reached home.

Any clue? All the above instances I had A/C ON.

Any chance that your water lines to get blocked after the radiator flush? Did you flushed it after removing?