Do I need a new radiator? Temp gauge shoots stright up

[Ken Styles]

Hi guys,
I have a 97 sport and I was driving on the highway today..and out of nowhere that little "Check engine" light pops up in my face. I take a glance at all my gauges and my temp gauge was slowly rising right up to redline.

Not sure why. I just had the coolant professionally flushed 2 weeks ago and everything was fine.

I got off the highway..and the temp went down...

could this mean I need a new raditor?

 

[BrooklynBay]

Welcome to this forum! Your CEL came on. What was the code? Was your A/C on at the time when it started to overheat?

 

[Ken Styles]

No. the ac was not on.

I appoligize. It was the "check gauges" light. Not cel

Ken

 

[GJarrett]

Relace your thermostat before worrying about the radiator. Mine goes through a thermostat every 60,000 miles just like clockwork.

 

[Ken Styles]

ok i will do that...can someone direct me to a how too for changing the therm?


Here is an update as I was driving to work this morning.

-As soon as I started it...the temp went right up to the top. Not red lined but near.

-Then when I started driving a little bit it went back down.

-Then when got in the highway it went up and level out...and then about 20 mins later when I got off the exit it went up to red line.

I let off the gas and it stays up. I give it gas and it stays up.

so I keep driving and out of the blue...it goes down????

no rhyme or reason :shrug

 

[je5]

Do you have the OHV 4.0? If it turns out to be a worst case senario and a head is cracked I have some replacements on the shelf that need to be moved out. Hope it is just the 'stat. An errant chip from the flushing may have stuck your 'stat closed. Hopefully the flushing was "professional" because doing it wrong can crack those thin casting heads. Good Fortune

 

[cculter]

The cool air blowing over your engine will help keep it cold. Your thermostat might not be completly shot, just "sticking". As for help fixing it I would buy the Ford Haines manual. It has helped me countless times.

 

[Ken Styles]

ok...thanks guys

i just tried to burb it and see if there may be an air bubble. I took of the radiator cap...started the engine and the needle shot straight up! (mind you the engine is cold)

then I let it run for a few minites and the need stayed up.

so i put the cap back on and shut the engine down

 

[BrooklynBay]

If your temperature gauge goes up when it is cold, then your sending unit might be bad. Unplug that sending unit to test it. Your gauge should drop down (completely off). If it is still high, then there is a short somewhere.

 

[GJarrett]

Okay, maybe I didn't make myself clear.

CHANGE YOUR THERMOSTAT!

Sheesh.

.
.
.
.

Then again, it may not matter now.

then I let it run for a few minites and the need stayed up.

If you went ahead and intentionally ran it hot, you now could be looking at a heckuva lot more damage than a measly thermostat.

 

[cculter]

Try this: Take out the thermostat and put everything back together without a new one installed. If it still gets hot then you have a bad sending unit.

 

[Ken Styles]

so what you're saying is change the thermostat???


I'm kidding I'm kidding.

thanks buing a new therm now.... it costs a WHOLE $6!...lol

 

[Ken Styles]

Ok I changed the thermostat

and it kept shooting straight up to red line STILL.

Even after sitting over night with a cold enigine

so I took it to a mechanic... He said that the gauge cluster is bad...and that it will cost $90 and $175 to install it.

Does that sound right???

 

[GJarrett]

I still would have bet on the thermostat, but evenso it was smart for you to try a $6 fix before going on to things that are a lot more expensive. My second choice would now be the radiator. BTW, you've never said which engine you have and how many miles are on it so we're kinda guessing blind here.

If you've taken it to a mechanic and he says its a bad gauge, I don't know how much he should charge. Nevertheless, is he going to guarantee that is the problem and after he repaces all that and if it still does it, will he refund your money? I'm on my third thermostat and second radiator, but my gauges still work. If you've got a lot of miles on the radiator and you've used tap or hose water instead of distilled water it's a possibility that your flush job loosened up some corrosion in your system and you've got some coolant channels plugged up in the radiator.

I'd make sure the mechanic guarantees his fix so you're not out any money just in case you do end up replacing the radiator anyway. If he won't guarantee his analysis then I'd find another mechanic that's competent enough to believe his own diagnosis and stand by it.

 

[Ken Styles]

True indeed!

Thanks for all the help

It's a 4.0 SOHC with 98,000 on it

 

[rookieshooter]

If your gauge shot right up even before the engine had a chance to even heat up then it probably is your gauge. I agree with Brooklyn on this one.

 

[GJarrett]

Oops - I flat missed that little point. Yep, if the gauge shot straight up even though the engine was still cold, it would have to be the gauge or the sensor (or the wiring in that circuit). My bad. I still have a tendency to always try the cheap/easy fix before spending lots of money; I cannot count the number of times I've spent wasted hours and money doing a big fix when it ended up being something simple and cheap. I did misread your post about it reading hot even when the engine was cold, so it's my bad.

Oh well, with nearly 100k miles on it, your thermostat was about to go out anyway, so now you've preemptively prevented a problem you was about to have anyway.

 

[mattyt000]

just wondering, if his ac was on what whould you have thought...

 

[ProjectAviator]

That is way I purchased a Autometer temp guage. So I can watch and see exactly what temp the truck is running at.

Does the truck need to know the temp to run properly, computer wise.

Tim

 

[draft]

Check your head gaskets... that was my fix.