12/13/05 Update: Wacky temp gauge and No Heat

[cutlass93supreme]

ok guys im new to the board, but my cars not, (93 Cutlass Supreme 3100 SFI V6) my brother had it and got in an accident and now i have it. Ok so to the point, i put the car on the road in the middle of november, the car ran fine everything in working order, then it started to get really cold(i live in MA), one morning i turned the car on, let it heat up for about 8 min or so, then started to drive to school, once i was about 3 miles from home i noticed i was still freezing cold the heat was blowing cool air, so i look down at the temp gauge and it is almost at 12 oclock, and the thermostat is a 180, so i kno this isnt good, so i pull over into a parken lot, shut the car off for a lil bit(maybe a min or so to make sure it wasnt just sum thing in the computer needing to be reset), turn it back on and the gauge still reads that but then all of a sudden drops down to the 180 were it should be, so i continue to school. Once i get home later that day after school i tell my dad, he goes checks the coolant level, tops it off, it wasnt really too low, but its kinda brownish rusty looking, so we decide to flush it later that night. So we flush the coolant, drain it out, put "flush" and water in do all that, and add new coolant. The next day my dad takes it to work and it does the same thing to him accept the heat was even colder. So then we decide to change the thermostat u kno thinking you have to start somewere. Ok so we just got in from doing that except that didnt fix the problem eather, now the heat is blowing colder then ever and the gauge is still going up to 12 oclock.

 

Ok now the question WHAT DO WE DO NEXT?

 

ps. sorry for the huge run on, and sorry its so long

[Crazy K]

feel all the hoses, are they hot? make sure the car actually does get hot... first...

 

It sounds like you have my problem, a clogged heater core. Read this thread... I've got two to change...

 

http://www.w-body.com/forum/viewtopic.php?t=36705

 

Try disconnecting the return line from the heater core, (on the 3.1 it should link to a balck return pipe directly above the waterpump) I disconnected mine and ran the engine with the pipe loose, it should spew water, but hold a finger over the port that recieves the line to prevent spewing there. (mine trickled) what does that do?

[cutlass93supreme]

the uper and lower hoses of the radiator r getting warm but not hot like they should and the pressure doesnt feel quite right, the houses that r going to the heater core seem to be staying cold

[Regal_GS_1989]

The cooling system has to be bled of all the air in these cars. Its kinda rare to have a 3100 SFI in a 93, since it was really introduced in 94, but they should be the same. There should be 2 bleeder screws. One on the metal coolant crossover pipe, right by where it attaches to the water pump, and one on top of the thermostat housing. I have never had to bleed the system on a 3100, so i am unsure of the exact procedue. :oops: I believe that you start the car, and open up the bleeder screw on the coolant crossover pipe. Once there is just coolant comming out (no air) You close it and let the engine warm up so that the thermo can pop open. Than you open the screw above the thermo housing and wait till there is no air comming out. Than you should check the coolant levels in the rad once the car cools down and top it up if nessesary. Like i said, i have never done this on a 3100, so someone can correct me if i am missing anything, or if im wrong.

[birdman]

sounds right to me, had the heat ever worked?

[cutlass93supreme]

the heat had worked awsome for the past month that ive had it, and when my brother had it

[birdman]

what temp is it reading at 12 o'clock, should be about 200 i belive.

[cutlass93supreme]

its about 240 ish give or take 5 degrees

[birdman]

does the gauge start there or does it start cold and work its way up?

[cutlass93supreme]

it starts cold then builds its way up

[birdman]

well that means the temp gauge sender is working (most likley) and you have somthing blocking flow or a bad water pump. water pumps are fairly cheap and easy to install, is there any rattling coming from the engine or is the WP pully loose at all??

[94CutlassSLCoupe]

my guage actually reads 10 degrees high, they aren't that terribly accurate, although i would bleed the system.

 

The 3100 does have the bleeder screws on the thermostat neck and also one directly above the water pump. Get the car warmed up, open them up until coolant starts dribbling out and close it. Then let the car cool down and check the coolant level. Top off as needed and your heat should work well as long as the heater core isn't clogged, and your heater controls are operating properly. Can you switch between defrost and vent?

[Regal_GS_1989]

its about 240 ish give or take 5 degrees

 

OUCH!!! :shock: Hope that you didnt crack the heads Last time my car got that hot, that was the result

[cutlass93supreme]

birdman- there is no rattling coming from the engine, and the WP pulley isnt loose at all

 

94CutlassSLCoupe- yea i can switch between defrost and vent and heat and all them

[birdman]

do the fans kick on at 210 or whatever?

[cutlass93supreme]

i cant say that i have seen the fans kick on

[birdman]

so the upper and lower rad. hoses dont get hot just a little warm when the car is up to temp? if so you have a major clog in the coolant system somewhere or a bad water pump.

[cutlass93supreme]

ya there just getting a lil warm not hot tho

[birdman]

i would replace the WP and see what that gets ya and then go from there but you might want to check as many lines as you can going to and from the WP for blockage because the coolant cant get to and from the engine through the rest of the system including the heater. it might not be a good idea to drive it too far to because you dont want it to overheat and crack the head like regal said.

[cutlass93supreme]

thanks for the resonds guys, and dont worry i havent been driving it since this happened on like wednesday i think

[birdman]

no problem, if you have any more questions dont hesitate to post or of you want pm me.

[cutlass93supreme]

thanks, ttyl

[Crazy K]

i changed my heater core in the lumina, the old one was restricted... I force flushed the old one out and it cleared some junk out of it.... but after putting it together, I still have no heat. the lineout metal thing that everyone hates is aparently holding a clog.

Thats my experience so far.

I'll take that fitting off tomorrow and make sure everything is clear... this may be something you might have to do as well. Read the thread I started and already provided a link to for more tomorrow.

 

oh yeah.. how about trying a new thermostat? maybe yours is hungup?

[cutlass93supreme]

ok guys me again so 2day my dad and i bleeded the system 2day, bleed it for quite sum time a ton of air came out, but it still didnt solve the problem. So after bleed we left the car running, the temp gauge keeps going up, goes up to the red zone like just hits it then ya turn on the heat and it is a teany bit warm, then it gets ice cold after 30 seconds, so then all of a sudden it starts to drop down quickly, till it gets to 200 then the heat is hot the way it should be then after 30 seconds it gets cold and the temp gauge rises, a vicious cycle. What do we do next??

 

Crazy K- we already replaced the thermostat yesterday

[Crazy K]

ok. In mine the fitting for the line was clogged as well. (as wrapped in my post)

 

Does the engine actually feel hot?

Do the fans turn on? (you said you actually haven't seen it, try the autozone key, as if to check engine codes on the OBD I, as doing so should turn on both fans, btw)

Does the line to the heater core actually become hot?

How about the return line?

 

It still seems like you need to keep bleeding the system...

 

note that I have also seen a few bad temp sensors, both types, ones that read TOO hot, and that tell the engine that it is running cold when hot.