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Discussion Starter #1
I understand that the weather is cold, but we've had cold winters before and didn't notice the car needing this much time to warm up. I replaced my thermostat last year because it would not warm up AT ALL. I even took a picture once, after about a 60 km drive, the temperature was still at 50. Replaced the thermostat and it would heat up very quickly, in about three to five minutes the car would be blowing hot air. This is no longer the case.

The weather temperatures then were possibly around -5 to 5 degrees celsius. So current weather is a bit slower, but could this make such a big difference? Was driving around yesterday, and when I stopped in front of my girlfriend's home, to drop her off, I noticed that the temperature of the engine was at the first bar (60 celsius), so it was warming up. The engine was idling for maybe a minute, not more than two, and the temperature dropped all the way back to slightly above 50, maybe 51.

Now, if this is not the thermostat? What could it be? Does cold weather have such a big impact on it? What is there that I can do to help the engine warm up faster? Top up coolant/antifreeze?
 

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Does sound like thermostat isn't closing properly.

Is it Petrol or Diesel?
 

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Thermostat might be staying open, you might not need to replace the whole thermostat block,just the temperature sensor there if it's a 1.9JTD(the sensor that tells the thermostat to open or close).
hook it up the a diagnostics tool and check
 

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you might not need to replace the whole thermostat block,just the temperature sensor there if it's a 1.9JTD(the sensor that tells the thermostat to open or close).
That isn't how it works.
The temperature sensor tells the ECU what the coolant temperature is.
The thermostat is a simple mechanical device that opens & closes on its own.
 
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Discussion Starter #5
Does sound like thermostat isn't closing properly.

Is it Petrol or Diesel?
Diesel. However, last year it wouldn't warm up from 50 AT ALL. Now it does warm up, but very slowly, and cools down very quickly afterwards.
 

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Diesel. However, last year it wouldn't warm up from 50 AT ALL. Now it does warm up, but very slowly, and cools down very quickly afterwards.
Diesel's don't produce the excess heat of a Petrol so will loose heat very quickly.
The auxiliary heater is a good option for Diesels in cold climates!

Does it still have the EGR/coolant heat exchanger?
 

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Discussion Starter #7
Diesel's don't produce the excess heat of a Petrol so will loose heat very quickly.
The auxiliary heater is a good option for Diesels in cold climates!

Does it still have the EGR/coolant heat exchanger?
I never touched the EGR and I'm not sure what the heat exchanger is, either. But I haven't touched, removed or modified anything in the engine department, apart from the usual filters (and the thermostat, done by a mechanic).
 

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That isn't how it works.
The temperature sensor tells the ECU what the coolant temperature is.
The thermostat is a simple mechanical device that opens & closes on its own.
I had a similar problem on my 156 and I replaced the temp sensor and that solved it, but eventually I had to replace the whole thermostat block*. my car didn't even have the OEM radiator so that might not be the same case. I highly doubt it is the thermostat, rather investigate what could be causing it to fail.
here's a picture of the sensor i'm talking about, in the context of what David said, it should have no thing to do with this issue but it's worth checking it anyway, it's alfa romeo ! the whole ABS ECU fails because it didn't like a new battery. :nuts:
 

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here's a picture of the sensor i'm talking about,
That is the coolant temperature sensor.
It doesn't control the thermostat, it just sends temperature signals to the ECU and temperature gauge.
 

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Simple test for the thermostat, no equipment needed, the only thing you need is a hand.

Start the engine. Let it idle.

After about 3 minutes of idling the temperature gauge will still be zero, and the engine will be "cold". If the top rad hose is warm in the slightest - then the thermostat has failed. It should not warm up - it should be "cold", then the thermostat opens and it becomes "hot".
 

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+1 for a thermostat that leaks water into the radiator when the engine is cold.
I would say you need to change the thermostat one more.
Who is the vendor of the thermostat you put in last year?
 

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A lot of the after market thermostats seem to suffer small leakage when new even with the valve plate tight closed. The Alfa original stats seem to be leak tight. Doesn't seem to take much leakage on a diesel in cold weather to cause problems maintaining temperature. A blocked EGR will make the problem worse still since some of the EGR flow heat is dumped into the coolant.
 

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OP's car is a 147 ? Does it not have 2 sensors like the 156 David ? One for the gauge and one for the ecu ? If so could be his gauge/sensor is mis reading.
 

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OP's car is a 147 ? Does it not have 2 sensors like the 156 David ? One for the gauge and one for the ecu ? If so could be his gauge/sensor is mis reading.
No, 147 and gt only have 1 sensor, read by ECU. ECU then passes processed temp via CAN to guage ....
Only 156 has 2 seperate sensors, one for ecu and one for guage.
 

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Discussion Starter #15
OP's car is a 147 ? Does it not have 2 sensors like the 156 David ? One for the gauge and one for the ecu ? If so could be his gauge/sensor is mis reading.
If my gauge was mis-reading, I'd still be able to get hot air in, right? As of now, I have to wait until at least 60 to get slightly warmer air inside the cabin.

Also, I have no idea what brand this thermostat is, but it was about 35€ (around 28 pounds I think).

I'm thinking about putting some cardboard infront of the radiator, how much should I put?
 

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Also, I have no idea what brand this thermostat is, but it was about 35€ (around 28 pounds I think).
£28 is VERY cheap for a 1.9JTD thermostat...
 

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Simple test for the thermostat, no equipment needed, the only thing you need is a hand.

Start the engine. Let it idle.

After about 3 minutes of idling the temperature gauge will still be zero, and the engine will be "cold". If the top rad hose is warm in the slightest - then the thermostat has failed. It should not warm up - it should be "cold", then the thermostat opens and it becomes "hot".
This.

If my gauge was mis-reading, I'd still be able to get hot air in, right? As of now, I have to wait until at least 60 to get slightly warmer air inside the cabin.

Also, I have no idea what brand this thermostat is, but it was about 35€ (around 28 pounds I think).

I'm thinking about putting some cardboard infront of the radiator, how much should I put?
Your thermostat is broken again as lots of people have told you. Do the above check, replace it with OEM and forget mucking about with cardboard.
 

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Certainly check your thermostat, but if Bosnia & Herzegovina qualifies as a 'cold climate' (sounds like it should) then your car probably has the auxiliary heater David C referred to. This is an electric heater that heats the coolant (!) just before it goes into the cabin heater matrix. This having failed may be why you now have to wait for 60 on the gauge before getting warm air. (It also helps the engine warm up.) If you are handy with a multimeter you can check it yourself.

My diesel takes forever to warm up at 0C, so at -15 I can imagine it struggling to hold temperature when idling. I tried the cardboard trick, and it did help a bit. Details (rather too much) here:


http://www.alfaowner.com/Forum/alfa-147-156-andamp-gt/768186-how-much-cooling.html
 

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Discussion Starter #20
Certainly check your thermostat, but if Bosnia & Herzegovina qualifies as a 'cold climate' (sounds like it should) then your car probably has the auxiliary heater David C referred to. This is an electric heater that heats the coolant (!) just before it goes into the cabin heater matrix. This having failed may be why you now have to wait for 60 on the gauge before getting warm air. (It also helps the engine warm up.) If you are handy with a multimeter you can check it yourself.

My diesel takes forever to warm up at 0C, so at -15 I can imagine it struggling to hold temperature when idling. I tried the cardboard trick, and it did help a bit. Details (rather too much) here:


http://www.alfaowner.com/Forum/alfa-147-156-andamp-gt/768186-how-much-cooling.html
Ill read it when I get home. What about those dashboard heaters that plug in the lighter? They go for 15??. Wont certainly help the engine warming up slowly but will prevent me from becoming an icecube, I figure.

Also we USUALLY dont have such cold winters here. Newspapers claim this is our coldest winter in about 60 years.
 
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