PDA

View Full Version : Cooling issue...don't know what to think anymore



Chuckdee
03-15-2012, 08:55 PM
So this past saturday, I pulled out of a parking lot slow and all of a sudden I hear a noise under my hood, as If i ran over a couple of rocks. Turns out the fan shredded into pieces from hitting against the radiator which created holes into the radiator. I was about 15 mins from home. Thinking i can still make it home, I basically feathered the gas to slowly get it home. less than a light away from my house, the car shuts off (i guess from running too hot with very little coolant in it's system) and would barely crank over. I pushed it into a parking lot, let it cool for a couple of hours and gently drove it home at night.


Fast forwarding to tonight, I replaced the radiator and the fan blade and found the rubber spacers for the radiator to sit on (idk why the previous own thought it would be cool to NOT put those in) did a coolant flush, filled it up with coolant and now I have an issue. The temp needle would sometimes go between the 1/2 mark and the next mark towards the but whenever I'm driving at low rpms or coasting it would go back to the middle. I don't know what I'm missing here, am i forgetting something? is it a faulty temp. sensor? Is there a way to figure out that it is the issue?

I'm driving an 01 1.8t

Seerlah
03-15-2012, 09:06 PM
Either thermostat or coolant temp sensor. Both are cheap and easy fixes.

Thermostat :$20 shipped
CTS: $15 shipped

Chuckdee
03-15-2012, 09:14 PM
If i decide to change out both, it should fix the problem, right? I minus well buy both for good measure.

Seerlah
03-15-2012, 09:21 PM
I had an issue with my coolant temp not staying in the middle all the time. It was random. Sometimes it would stay, other times it wouldn't (not overheating, though). I changed out my CTS a couple weeks ago, and that didn't fix the issue. I then ordered a thermostat, and I have yet to start my car because I am doing other stuff to it. The t-stat replacement should fix my issue.

But it should be either one or the other. I am leaning towards thermostat. People say don't fix it if it isn;t broken, but I would replace both of them simply because it really isn't that expensive when compared to other repairs these cars need. $35?

http://www.mjmautohaus.com/catalog/product_info.php?cPath=6169_6170_6186_6188_6726_89 84&info=OEM_VAG_059919501A_Coolant_Temperature_Switch _with_O-Ring_Green&products_id=1207
http://www.mjmautohaus.com/catalog/product_info.php?cPath=6169_6170_6186_6188_6726_89 84&info=Behr_050121113C_Thermostat_with_O-ring_OEM&products_id=1557

And for the thermostat, no need to loosen the alternator. Unhook your negative terminal from the battery, unhook the black wire on your alternator (for clearance to get to the top hex bolt), and use a long 5mm extension to remove the flange to get to the t-stat.

http://i228.photobucket.com/albums/ee147/seerlah/DSC03332.jpg

Chuckdee
03-15-2012, 09:29 PM
^yeah good thinking. Is there a certain temp on the t-stat i should go for? Also before the incident, The temp gauge from time to time to lean a little past 1/2 whenever left idling for a good while but would go back to the middle a little bit later on. I thought it was because the type of coolant the PO put in before i got the car. It was green coolant and after finding out that We needed g-12 I was assuming that was the problem. Although I also researched that Dex-cool isn't bad for our cars..?

Chuckdee
03-16-2012, 11:42 AM
So I replaced BOTH the Coolant temp sensor and the Tstat, and it's still doing the same thing. I'm currently Running dex-cool in my system (did a complete flush before adding dex-cool) dunno if that makes a difference in why the temp keeps leaning over to the right side. Does anybody have any suggestions?

Seerlah
03-16-2012, 01:32 PM
I would only run G12. If not your coolant, then maybe something is up with your radiator fan.

And sorry the parts I told you to order did not fix your issue. They usually do.

FNK
03-16-2012, 05:45 PM
If you have a plastic water pump impeller, it too could have suffered damage.
Also, is the electric fan turning on?

biketsai
03-16-2012, 07:11 PM
Ive ran dex cool for the past 4 years without any problems. I doubt the coolant is the issue

Avant Nate
03-16-2012, 07:25 PM
I've run G-05 for 2 years and no problem. Not a big fan of dexcool because that's what I run in my GMC and cooling system issues is one of the only problems I've had. Someone did a test of all the different types of coolants a while back, and G12 faired the best, with G05 right behind.

SGS
03-17-2012, 11:53 AM
I had the same issue and my car was not overheating but the temp guage was saying it was.... one day when i was driving home from the bar my car did over heat and i noticed i cracked the coolant flange... the flange is a cheap plastic part and i replaced that and filled my coolant back up and was still having the same issue... I decided to just buy the waster pump/timing belt kit from blauparts.com for about 350$ and when i got the water pump off the impellar was completly split in half because it was PLASTIC WTF!?!?! After changing the water pump my car has since over heated but the stupid thing is the kit comes with a pump with a plastic impellar so if you know your bels and everything is good i would upgrade to the metal impellar water pump and that should fix your issue. ***** ALSO ***** there is a way to see if your impellar is bad. you can take the hose off thats closest to the pump (bare with me its been almost a year since I've replaced the water pump) and with a screw driver you can stick it in there and see if there is any free moving impellar pieces in there... Someone help me out with exactly which hose it is.. im leaning towards the hose with the thermostat in it but dont take my word on that one.

Chuckdee
03-17-2012, 11:53 AM
The coolant isn't the issue but what i've discovered is that i'm doing the cool flush wrong. According to the diy you're suppose to run a water hose through the tank while the coolant is draining out from the plug where the red screw at the bottom of the radiator is, THEN screw back in the screw. I'm gonna try the flush again and see if i can get all the air out.


Does anybody know where the air bleeder screw is on the 1.8?

FNK
03-17-2012, 01:11 PM
Does anybody know where the air bleeder screw is on the 1.8?

No but you can open the tank once the car reached the working temperature. *Of course, use a cloth over it.
If there is air bubbles, you will hear them. Do it a couple of time and your done.

Chuckdee
03-17-2012, 03:02 PM
No but you can open the tank once the car reached the working temperature. *Of course, use a cloth over it.
If there is air bubbles, you will hear them. Do it a couple of time and your done.

yeah I'm try to do that. Well it seems like NOTHING is working. Must have flushed the system all afternoon today and still no solution. my last resort is Water Wetter, which I just bought, and see if that fixes the problem and I'll still try to research possible ideas. if not ima take it to a shop on tuesday....and I HATE going to the shop.

FNK
03-17-2012, 05:20 PM
Before going to the garage.

Is your fan clutch still good? A broken fan clutch will not pull much air true the radiator.
Look on Youtube for "Fan clutch test". You try to stop the fan from spinning using a rolled journal. If no resistance, then it's shot. If it take some force to stop it, then it's good.
Also, is your electric fan working?
Your coolant reservoir cap is holding some pressure? (Unpressurized coolant will boil and overheat the engine).

Chuckdee
03-18-2012, 02:39 AM
did the fan clutch test and it's still good. is there any way to test the electric fan? the threads on the cap is pretty much gone like it's hard to screw on/off at times but i think it's still holding pressure.

Aragorn
03-18-2012, 02:53 AM
The bleed hole on ALL B5's is one of the hoses on the heater matrix.

You just pull it half way off the barb to expose the little hole, then fill the expansion tank until water comes out the hole.

Thermostat faults usually cause over cooling, rather than overheating. I'd suggest its a broken impeller on the water pump.

FNK
03-18-2012, 05:40 AM
The electric fan kick in when you use the AC (set it at the minimum temp until it write LOW).
It can is also be activated by engine high temperature (help prevent overheat). Mine wasn't working, and the engine would run too hot until I changed my electric fan, now it's perfect.

Edit, another thing.
Running 5w-40 oil [Castrol Syntec] would level my oil operating temp to 225F+ on the highway.
Running 5w-30 oil [Quaker State Ultimate], reduced it to ~205F in the same condition (engine load, speed, same laps of time).
The lower temperature of the 5w-30 vs the 5w-40, make the viscosity approximately the same. (12.0 cST vs 12.8 cST IIRC)
Now playing in the snow will no longer overheat either the coolant or the oil.

Chuckdee
03-18-2012, 11:12 AM
The bleed hole on ALL B5's is one of the hoses on the heater matrix.

You just pull it half way off the barb to expose the little hole, then fill the expansion tank until water comes out the hole.

Thermostat faults usually cause over cooling, rather than overheating. I'd suggest its a broken impeller on the water pump.

I replaced the fan blade already, is there a certain way i'm suppose to mount the fan blade onto the clutch? also I saw that little hole at the Heater core hoses, i just didn't know how you're suppose to deal with that. But i'll go take a look at that in a few.


The electric fan kick in when you use the AC (set it at the minimum temp until it write LOW).
It can is also be activated by engine high temperature (help prevent overheat). Mine wasn't working, and the engine would run too hot until I changed my electric fan, now it's perfect.

Edit, another thing.
Running 5w-40 oil [Castrol Syntec] would level my oil operating temp to 225F+ on the highway.
Running 5w-30 oil [Quaker State Ultimate], reduced it to ~205F in the same condition (engine load, speed, same laps of time).
The lower temperature of the 5w-30 vs the 5w-40, make the viscosity approximately the same. (12.0 cST vs 12.8 cST IIRC)
Now playing in the snow will no longer overheat either the coolant or the oil.

Also I don't see the electric fan coming on whenever I turn on the a/c and set it to low, yet again the system doesn't have freon in it yet, would that be the culprit? I did do an oil change and I think I used 5w-30 but it was Pennzoil full synthetic.

Chuckdee
03-18-2012, 02:13 PM
well i pulled back the heater hose w/ that tiny hole and coolant was flowing out and I also held up the res. tank and saw a couple of bubbles come out for a couple of mins but that still didn't do anything. Ugh :/


I'm temped to switch back to the old coolant temp sensor to see if the new one is the problem. it's a stretch but I don't know why it keeps tilting past normal temp.

By the way, the temp needle only tilts in between 1/2 and the next notch towards hot. It doesn't even go past it after being left to idle for a while, as if it's telling me the coolant temp. is bit higher than normal and Idk what's the cause behind it.

Avant Nate
03-18-2012, 02:43 PM
It is probably the water pump impeller.

Chuckdee
03-18-2012, 05:06 PM
^^i was thinking of that too. but another part of me was thinking what would the water pump have anything to do with the overheating?

Avant Nate
03-18-2012, 05:44 PM
Thats why it would overheat, no pump = no circulation=overheat

FNK
03-18-2012, 06:03 PM
If I where you, I would pull the water pump and be done with the guessing.
An if your electric fan is broken, you should replace it. FCPgroton sell a replacement for around 100$

redline380
03-18-2012, 07:58 PM
i vote for the pump too. when was your last tbelt service? if it was a while ago it makes all the more sense to do it. and get a metal impellar.

Chuckdee
03-19-2012, 08:42 AM
Thats why it would overheat, no pump = no circulation=overheat


If I where you, I would pull the water pump and be done with the guessing.
An if your electric fan is broken, you should replace it. FCPgroton sell a replacement for around 100$


i vote for the pump too. when was your last tbelt service? if it was a while ago it makes all the more sense to do it. and get a metal impellar.


Found out the electric fan still works, it came on for a bit after driving for a while last night. And I guess i'll replace the pump. Maybe it's not getting enough circulation? I don't know but i'll replace it and see if it will work.

Chuckdee
03-19-2012, 12:19 PM
Well I just replaced the coolant tank with a new cap, the threads on the old one were mostly gone, so it wasn't able to twist on/off properly. Hopefully this will fix it, i won't know for now until I leave work.

Chuckdee
03-21-2012, 08:47 PM
Can a failling water pump cause these symptoms?

FNK
03-21-2012, 09:11 PM
Can a failling water pump cause these symptoms?

Yes