Coolant (and heating) Issues

[Batmobile_Engage]

I started noticing this issue about a week ago, but it seems to have become
a bit worse, as well as noticing a new symptom.

(A short back story first: A few months ago I was having issues of high coolant
temps. I ended up narrowing it down to a bad thermostat that was seized shut.
I replaced that (and every bit of coolant) with a Grimmspeed thermostat that is
even cooler than the OEM thermostat. Problem solved.....
.....until now.)

Most of the time in daily commutes, I'm sitting in traffic, so I'm not horribly surprised
that the temperature climbs slightly. It's been happening faster now and getting
hotter than before, so I figured "I'll bet my fans aren't running, simple blown fuse again
or something stupid". I checked, and both fans are running.

In the past, if I had coolant issues, I'd turn the heat on full blast to give the system
an extra heat sink (heater core). It would blow suuuuper hot air and then I'd fix the
issue, etc....

Just a few minutes ago when I ran out for lunch, I noticed again the temps rising. I put
the heat on full blast and nothing but cool air is coming out. THIS has me worried.

There are only so many things that can go wrong in a cooling system. WTF could this be?
Water pump?

 

[IGOTASTi]

Do you have a digital temp gun?

Also when at idle does the fans kick on and stay on?

 

[Grinder34]

You sure the system is burped properly and no air pockets?

 

[Batmobile_Engage]

Grinder:
I am pretty sure there are no air pockets, but sometimes it seems that I can be sure of nothing until I confirm
one way or another. This will be my first course of action.

JJ:
No I do not have one of those....wish I did though. The fans seem to go off when I am at speed, and the temp
goes down, then I sit in traffic for a while, temp goes up, I turn the corner into my parking spot at home, open
the hood and the fans kick on almost instantly. The run for 30-60 seconds and shut off. It idles for a couple
minutes and the fans kick back on again.
When you're looking at the factory coolant temp gauge, it has 4 marks. 1-totally cold (0%), 2-operating temp (40%),
3-high temp (60%) and 4-holy shit, I'm about to explode (100%). The fans kick on just above the second mark.
So......45-50% needle deflection.

 

[Spamby]

classic signs of air lock. They can be very frustrating and difficult to get rid of.

 

[Batmobile_Engage]

classic signs of air lock. They can be very frustrating and difficult to get rid of.

I hope it's just that simple.

On a side note, to cover all the bases.... What about my water/coolant pump? Honestly, I know nothing about the
pump on our motors. What about a temperature sensor/sending unit/etc...?

Also, I recently drove 600 miles with no issues at all. I suppose it still could be air in the system though, right?

 

[HolyCrapItsFast]

If you have an AP or a Tactrix or a scan tool you can monitor the coolant temp to see what it is doing. It should hover around 190-195ish while driving and it it shouldn't ever go much above 212 in most cases. IIRC the fan's don't come on until 212.

If you don't have any heat then that means there is either no circulation or there is air in the system.

 

[Batmobile_Engage]

^ That's why I was concerned about the pump....I figured it could be shot when I wasn't getting any heat.
How do you determine that the pump is bad without simply replacing it?

I will use my AP later to determine exact fan turn-on temp.

 

[Spamby]

Coolant is full? Very low coolant can do this. At idle the engine temps rise and the heater output decrease. When on the throttle the engine temp decrease and heater temp increase.
System not holding pressure can do this as well. Crack in tank, radiator, etc.
Water pump should have a weep hole. Often times drips of coolant will come from that when water pump is bad. But no guarantee. Remove belt/ pulley on the pump snout and wiggle. If there us play, bearings are bad.

 

[Spamby]

Remember that coolant sensors only measure coolant temps. If there is no coolant to measure, your gauge will never read correctly.

 

[Batmobile_Engage]

Got it. Thanks Spamby. Yes, I believe coolant is totally full....BUT....I'm assuming at this point that there
may be some air in the system. I'm going to burp it repeatedly when I get home from work.

 

[HolyCrapItsFast]

Remember that coolant sensors only measure coolant temps. If there is no coolant to measure, your gauge will never read correctly.

It will also read the temp of any steam... which is almost always a component in a system low on fluid. :tup: When My car last overheated there was very little coolant in the system but the temp pinned the needle even though the sensor saw no coolant.

 

[Batmobile_Engage]

Also, it seems like I should know this, but idk why I'm not clear on it right now...
I have a little bit of coolant in my overflow bottle right now, but it's very little.
If the end of the hose in the bottle isn't submerged in coolant, could the system
pull in air through this hose (when the engine is cold and the system attempts to
intake overflowed coolant), rather than coolant? I used to think so, and so I'd
keep it 1/3-1/2 full. The reason I stopped doing that was that, when I'd auto-x
in the summer in south Florida, my coolant would be in the acceptable range, but
a little bit high. (It gets retarded hot in the Keys in the summer.)
The increased temp causes a little bit of coolant to overflow into the bottle of course.
Well, since my Perrin FMIC was installed, I had to remove the OEM coolant overflow
bottle and install a smaller one from Perrin that doesn't obstruct one of the boost tubes.
With this smaller bottle being 1/3-1/2 full, and high track temps, enough coolant would
flow into the bottle to blow the lid off and mess up my engine bay. I removed somewhere
around 1/2-1 pint of coolant, and didn't have that issue anymore. HOWEVER, after removing
that amount of coolant, it doesn't appear that the end of the hose is submerged in coolant
anymore.

Could this be the cause of, or contribute to this issue?

 

[Batmobile_Engage]

The coolant is less than 4 months old. I will be burping the system this evening.

 

[Spamby]

The coolant is less than 4 months old. I will be burping the system this evening.

Hopefully that works but be forewarned sometimes a stubborn air pocket can only be remedied by draining and then refilling.
Food for thought.

 

[Batmobile_Engage]

Damnit :|

Thanks for elaborating. I didn't consider that.

 

[Batmobile_Engage]

I don't have the luxury of a place to do the work. However, I did just burp a huge amount of air out of the system. It then accepted about 3/4 gallon of coolant. I always check the spots I've parked in for any signs of leaks....of any kind. Nothing. I don't have a clue how I was low on coolant. I'm about to go for a drive. Brb.

 

[Batmobile_Engage]

I took a short but spirited drive and also sat in a bit of traffic. Things are much better. Not where they should be, but better. I need to burp the system again once things cool down a little bit.

 

[Grinder34]

3/4 gal is.....a lot. Dont the cars only take like 1.5-2?

Are you sure you're not burning coolant (blown head gasket or something)?

 

[Spamby]

Air takes the place of liquid hence the reason your low.
Burp that bitch some more