Overheating issue...

[hellraiser456]

My cars temp gauge is somewhat all over the place.

it starts out fine...warms up fine and then for no reason the temp will go up and then go down. It happens fairly slowly too. Worst time i have seen was cruising at 60km/h in third not boost and it just randomly started to rise. got up to just over being horizontal and the went back down to being the normal below horizontal (needle position)

In fear of a bhg i looked for some obvious signs and there were none....my coolant reservoir was fine (just barely above the full line). It was a fairly warm day so i figured that to be normal. the issue i find seems to stand out more when the engine is held at high revs...not necessary under load or boost. The rad cap looked ok.

Now i have noticed my coolant light come on in hard cornering lately. it will light up and then as soon as i come out of the corner it will go out. the reservoir is full though.

Mechanic friend of mine said its probably a water pump failing. i am thinking something is up with the coolant overflow system and its not putting enough coolant back into the system or something.

now i have a bad knock sensor so i know i am running hella rich. I also know my car is burning zero oil and there is no white smoke ( i had a friend follow me after checking everything out).

next time i am out and driving i am going to turn the heat on when it starts to rise because i remember hearing somewhere that helps diagnose the problem.

done some searching around but all i can really find is bhg issues.

I am looking for suggestions as i don't want to just start throwing parts at it.

Thanks in advance.

 

[Dunckel]

check your thermostat. sounds like it is getting stuck.

 

[supraman7mgte]

are you getting a good connection at the temp sensor?

 

[Bishop92t]

Check coolant via radiator, NOT via the overflow reservoir. The reservoir is not an accurate measurement of how much coolant is in your system, it's overflow for heat expansion only. Obviously only check the level in the radiator when the car is cold. It should be full to the brim.

If you haven't replaced the thermostat and radiator cap in a year then you should go ahead and replace those as a precaution. They're cheap insurance.

 

[hellraiser456]

cool i will check the rad level tomorrow. i will also buy a t stat and cap tomorrow to and let you know what the results are.

as for the temp sensor i did check the connection and it seems tight and dry with no corrosion. i assume it is as the temp gauge is doing nothing to suspect a bad connection. i had this problem before and you could tell it was something up with the temp gauge. it would would very quickly change and move around randomly. it stays steady and doesn't move quickly at all. when it moves up it does so very slwoly like i would think it should

Thanks

 

[pimptrizkit]

do a block check. it's gas chemical sniffer that looks for hydro carbons


from what i understand is at free way speeds you dont need a fan to cool your ride, and that if you dont have a thermostate that your car will run cooler,

any time one of these cars has any cooling problems it might be wise to use the block check

 

[bigaaron]

do a block check. it's gas chemical sniffer that looks for hydro carbons


from what i understand is at free way speeds you dont need a fan to cool your ride, and that if you dont have a thermostate that your car will run cooler,

any time one of these cars has any cooling problems it might be wise to use the block check

If you don't have a thermostat the engine will run HOTTER. Never run it without a thermostat. And never run it without a fan.

 

[hellraiser456]

do a block check. it's gas chemical sniffer that looks for hydro carbons


from what i understand is at free way speeds you dont need a fan to cool your ride, and that if you dont have a thermostate that your car will run cooler,

any time one of these cars has any cooling problems it might be wise to use the block check

im not going at free way speeds...i said 60 km/h so that's about 35mph.

i will try to check check for exhaust gases in the coolants. where do i buy this thing and about how much will it cost me. i assume that is what you mean.

and i can't run with out a tstat cause the weather here is a bit unpredictable and it can get cold sometimes and i like my heat. plus it doesn't sound safe in general because engines like to run at a certain temp. to me they are there for a purpose and thuis i see no need to remove it

my winter beater has a stuck open t stat and in the winter the engine barely makes it over the cold mark...and at times you have to bag the shit out of it just to get it to that....let alone the lack of heat. also too me that would mess with the ecu and it may not leave the cold idle and that sucks ass for gas milage and the fact you would be burning rich.

but back on topic....i checked the rad fluid and it was to the brim at stone cold (wasn't started for the day). i don't think im losing coolant.

Question though...when the rad light comes on...what exactly does that mean. i was always under the impression that it meant the reservoir was low. i would like to know a bit more about how that light comes one as it may be a part of my problem.

edit...im heading to work soon so i'll see if it happens again and i'll pay attention to when it does and what im doing

 

[suprahooked]

Sounds like air in the system, try burping it.

 

[starscream5000]

The sensor for the coolant light is in the resivoir bottle, check to make sure there's no foreign debris in it. It could also use a good cleaning probably.

Do you have your fan shroud on?

Do you have an engine undertray installed?

Does your fan howl constantly?

Can you spin your fan when the egines off and cold? How long does it spin before it stops abruptly?

 

[Dunckel]

yes, please let us know what the culprit was. i am curious.

 

[SDtoyomk3]

it sounds like the thremostat to me. i had a very similar prob and i replaced the thermostat and it worked fine after that

 

[bigaaron]

I had it happen to me, and about 50 friends, and it was a bhg.

 

[hellraiser456]

i didn't get a chance to run out and buy a t stat and rad cap. however...with much effort and stock boost i couldn't get it to rise under boost. That said it did creep up a bit but dropped right back down while cursing (no boost and not accelerating).

I do not think its a bhg solely because there are no other signs other than temp fluctuations. usually if you are getting combustion preasure in the lines...the coolant overflow tank will over flow...mine doesn't...nor does it even get anywhere near it...highest i have ever seen it is about an inch above the full line and that was on a very warm day and a fair amount of engine abuse. otherwise it will hover in and around the full line. i am also not burning any coolant or oil (yes i have checked)

i will clean the reservoir this weekend. i did notice that it looks a bit dirty on the bottom and the lin e that goes from it to the rad is as hard as a rock.

as for the fan shroud...yes i have one intact.

i do not have the under cover

im not sure what you mean by howl...but i do hear it spinning and pushing air (sounds like a diesel truck fan). when i notice it i would say its on fairly frequently. i haven't really paid attention to when its on nor in the last couple of days...i will also keep an eye on that. weather has been a bit crappy so the top has been on and its easier to hear with the top off.

spinning the fan is somewhat easy(a little resistance) but i would say it spins about 1 turn upon a fairly decent pull, if that. i will check again tomorrow when the car is stone cold.

EDIT: i spun it and it will spin maybe a half a turn.

as for air i will burp the system tomorrow. see if that helps.

thanks for the suggestions and i will get back to you asap...also if i have time i'll do a quick compression test

 

[Dunckel]

yup, thermostat. may as well replace your rad cap too.