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Car never gets past 130*, even when hammering

  • Thread starter Thread starter astronut1885
  • Start date Start date Jan 16, 2004

astronut1885

Founding Member
Jan 31, 2002
1,899
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39
Assonet, MA
Jan 16, 2004
#1
  • Jan 16, 2004
  • #1
Hey guys. I've noticed lately that my car's temp won't get hot. When I start it, it takes about ten minutes to rise to about 130*, and then it doesn't move. I can do runs on a back road, high rpms on the highway, you name it, and it won't get hot at all. I am thinking about getting an aftermarket gauge setup, but is there any way this could be accurate on the stocker?
 
Q

QCStang

Founding Member
Mar 28, 2002
813
1
18
Aylmer, Quebec, Canada
Jan 16, 2004
#2
  • Jan 16, 2004
  • #2
astronut1885 said:
Hey guys. I've noticed lately that my car's temp won't get hot. When I start it, it takes about ten minutes to rise to about 130*, and then it doesn't move. I can do runs on a back road, high rpms on the highway, you name it, and it won't get hot at all. I am thinking about getting an aftermarket gauge setup, but is there any way this could be accurate on the stocker?
Click to expand...


Stockers are far from accurate.

Try changing your thermostat.

Sounds like maybe your thermostat is stuck 'open'.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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129
Jan 16, 2004
#3
  • Jan 16, 2004
  • #3
you can check your t stat by squeezing the top hose when hot. also, take the rad cap off and warm it up. watch coolant flow from pass side to drivers side in the rad.

the stocker can be that far off. thats what mine reads when its winter time (tucson, still high of 75*). that is with new sender. the stocker reads ~40* cooler than my aftermarket gauge. then it will sometimes catch up.

aftermarket gauge is a necessity for stangs, IMHO. id do it and then if it is something else, replace it then. atleast you will be better equipped to troubleshoot it. i bet its the gauge.

good luck.
 
R

redterror302

Founding Member
Jun 29, 2002
895
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0
Mertztown, PA or State College, PA
Jan 16, 2004
#4
  • Jan 16, 2004
  • #4
Before you spend the 40 bucks for an aftermarket guage(which I do recommend), spend 5 bucks and get yourself a new thermostat. Same thing happened to me. The t-stat was stuck open. Threw in a new one and it was fixed. Your sig shows that a 180 t-stat is coming soon, just make it now an be done with it.

Chris
 

astronut1885

Founding Member
Jan 31, 2002
1,899
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39
Assonet, MA
Jan 16, 2004
#5
  • Jan 16, 2004
  • #5
the new tstat is going in with the new lower intake, and I am going to install a set of Summit gauges at that time too (voltimiter, oil pressure, and temp). Glad to know I am not the only one with a crappy gauge. Odds are the original factory tstat is in there, as the previous owners didn't know crap about cars and maintainence.
 

TheFleshRocket

Founding Member
Jul 10, 2002
208
0
16
Southern Ill Annoy
Jan 16, 2004
#6
  • Jan 16, 2004
  • #6
I concur with the "stuck-open stat" diagnosis.

Replace your stat and then, if you still have problems, play around with gauges.
 

The Shape

Founding Member
Jan 11, 2002
2,224
8
49
East ARKANSAS Delta
Jan 16, 2004
#7
  • Jan 16, 2004
  • #7
I debated for a while about getting aftermarket gauges. HISSIN50 finally sold me on getting the some time back when I was having oil pressure issues. After installing the new gauges I will say that is one of the best things I have ever done to the car. The stockers are very crappy. I run a 180* stat beacuse of the heat and humidity here in the summer time and with the stocker it just wondered all over the place. My auotmeter sets right on 180* unless I hammer on the car. If I ever buy another 5.0 I will buy a set of gauges before any other mod.
 

sixty9boss302

Founding Member
Jun 27, 2001
234
0
0
Pittsburgh PA or Rochester NY
Jan 16, 2004
#8
  • Jan 16, 2004
  • #8
How hard is it, and how long would it take in install a new t-stat in a 91 GT. I have never done it myself before, so any suggestions would be great. Also what temp, i think i would go with a 180*. thanks
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Jan 16, 2004
#9
  • Jan 16, 2004
  • #9
The Shape, thanks. glad i give decent advice every now and then.

ah, no one asked: what ambient temps are you seeing? does you heater kick out decent heat? im thinking with a stuck open stat, the heat would suck. above tests i mention help rule that out or confirm it. i really like the Mr. Gasket thermostats. they open fully sooner than parts store variety, are balanced, have bleed hole (saves you drilling you own) and only cost a few bucks more than the cheap generics.

69 boss, if doing an SN95 is anything like a fox, it is easy and hard. i found it to be a pain, as the driver side bolt comes out at like 1/84 of a turn at a time on mine. ten minutes later, its out. the pass side bolt is easy. then finagling the small hose off of it is a pain if the hose is old and doesnt come off. really not bad, just tedious. but takes 10-15 mins to do. two bolts, two hoses and out. dont overtighten the bolts, as housings like to crack.
 

astronut1885

Founding Member
Jan 31, 2002
1,899
4
39
Assonet, MA
Jan 17, 2004
#10
  • Jan 17, 2004
  • #10
My heater works great, and the hose only gets hot once the car reaches 130*.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Jan 17, 2004
#11
  • Jan 17, 2004
  • #11
to me, that suggests that your stat is at least partially functioning, and that the gauge is screwy. mine will read a lil' over 130 when im at 180-ish sometimes. i have to breach 195 or so to make it go higher.
 

The Shape

Founding Member
Jan 11, 2002
2,224
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49
East ARKANSAS Delta
Jan 17, 2004
#12
  • Jan 17, 2004
  • #12
One of those ratcheting box end wrenches would come in handy for the drivers side housing bolt I would think. I have an old 1/2'' wrench that I bent in a vise that makes it a bit easier to remove that bolt. And HISSIN50 is right that bypass hose can be a real pain.
 
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