Radiator fan going or ECT sensor?

[ret]

Wanted to get everyone elses opinion on the actual problem going on here. It appears either my radiator fan or ect sensor is shot... haven't checked codes yet to see if there is an ect sensor code being reported, but I have gotten no ce light, so I would imagine that there's not a code for it.

The engine heats up a whole lot, up to the N in normal when idling after I have been driving, as soon as I start moving and air starts flowing the engine cools down... on city roads(25-35mph), down to maybe the M, out on the interstate doing 60-70, the temp drops down so the needle is at the A or L as it used to always be. On occasion once the needle hits the N, the temp will drop down to the O or R then heat back up then drop down, etc as if the fan may be going on, just a little too late and not for long enough. Where do you guys think the problem is? ECT, fan, or possibly the thermostat? I'll post again after checking for error codes after work today.

 

[projectSHO89]

First, check your coolant level. Then, check and see if your fan works.

Turn the A/C on to MAX and look and see if the fan(s) is (are) running at high speed. I don't recall if you have one fan or two.

The 94 should run at 2 fan speeds. A low speed kicks in first when the ECT sees the temp hit its preset point. The high speed kicks in when it gets hotter or when the AC compressor is commanded to turn on.

The relays that control the fan speed are in the module that is on the upper radiator mount under the plastic plate that has the emissions stickers on it. There is also a dropping resistor in the circuit for the low speed setting. It is before the relays, according to the schematic.

You can get a diagram for this circuit (and more) from http://www.ford-taurus.narod.ru/9404.pdf The site is in Russian and is very slow, so be patient. The info you need is on page 9 of the PDF file, but it will provide you with the data needed to diagnose and repair the problem.

Your possibilities are: thermostat, ECT, temp sender (giving bad reading), EEC-IV, CCRM (relay module, fans, water pump, etc...

Steve
89

<small>[ July 31, 2002, 07:40 AM: Message edited by: projectSHO89 ]</small>

 

[ret]

Great, I'll give that a shot after work today.
Oh, and I have checked the fuse for the radiator fan with a multimeter to verify that it is good, so it's not that, unfortunately.

Looks like your AWA has the same opinion of the SHO as mine does... I get a request from her to just sell it and buy something else at least twice/month, heheh.

<small>[ July 31, 2002, 07:57 AM: Message edited by: ret ]</small>

 

[projectSHO89]

At least your's makes it a "request"...

Mine ran out of patience with my 93 Explorer this month (3rd tranny got cooked while towing boat). I could have fixed it for under a grand, but NoOOO... she had to have something new. Scored a good deal on a '00 Navigator. 330 Hp from a 5.4L

Steve

<small>[ July 31, 2002, 08:11 AM: Message edited by: projectSHO89 ]</small>

 

[ret]

haha, sounds like you got the good end of the deal. I just keep telling my gf that for what I could sell the SHO for, any other car I could afford would be just as likely to be problematic, so this way at least I've got the the irritating, troublesome, car that I want to have.

It won't be quite as big of a hassle once I get that capri here to va though, then it won't matter if the car has to sit for a week or two while I dig up money or will take more than 1 day to fix at a mechanics. Of course once she sees the gas mileage on that car and starts hearing complaints from neighbors saying my car wakes them up when I leave early in the morning for work, she'll probably try to get me to sell it too, heheh.

 

[ret]

Ok, just did koeo and koer tests, no error codes given. My radiator fans (94 has the dual fan deal) do appear to be coming on... I can't actually see them, but there's a whole lot of wind blowing up from them and in front of them. They appear to be on at full blast (the temp is fairly high, sitting at the R and occasionally rising while at idle for a few minutes) even without the AC turned on. So the fan seems to know it needs to be on, but it's hot anyway, or so the gauge says. Any ideas on what to do next? Keep in mind that I'm broke as can be right now and have little mechanical ability to do repairs myself and this is currently my only available car, so I have to be able to drive to work the next day (the lack of mechanical ability combined with this limitation tends to be a problem).

Oh yeah, and plenty of coolant, at least in the reservoire... what are the chances that most of the coolant is stuck in the reservoir so the radiator itself doesn't have enough to cool properly?

 

[SHOfun 93]

My sho runs quite hot right now as well (stays around the O quite often), and although we have quite a bit of 100+ degree days, I know for a fact that my radiator doesn't flow as well as it should, and it has a crack in the driver's side end tank, so I am going to replace the radiator to get a better flow of coolant through it so that it can cool properly. Flush the radiator with some prestone power flush and clean out the deposits. Try that. It is cheap, easy, and won't put your car down for really any significant amount of time.

 

[ret]

Cool, I'll give that a shot. The R and occasional lower O range don't bother me too much as it's generally 98-101+ deg here lately, too, just that upper O and N range, which are quite frequent are disturbing me.

 

[AutoSHO]

ret:
Cool, I'll give that a shot. The R and occasional lower O range don't bother me too much as it's generally 98-101+ deg here lately, too, just that upper O and N range, which are quite frequent are disturbing me.

I am willing to bet that the problem is your radiator. If you pull it out, there will probably be a coating of crap (mine looked like a lint trap!) Clean all that off and re-install the radiator, and you should be back around the L! Good Luck!

 

[ret]

That could be, as far as I know it's the original radiator, plus I drive on gravel a whole lot, so it's likely that it is really nasty. Also, I watched on my way into work today, it was only about 70 out as I go in real early, and the temps still got up to the O when I idled for a few minutes after getting the engine warmed up and driving a bit.

 

[pete c]

souns like a loose fan belt to me....or maybe a muffler bearing? wink

 

[shodazzl]

I have the same problem.I replaced everything,But no go. The only thing that might solve this problem, is to powerflush the block.Thats what I'm going to try.

 

[ret]

Well, I just semi-cleaned the radiator... went to the car wash and hit it with the power sprayer thingy. I could only get half of it good since the fan is covering the other half too much, which is probably where it's really filthy. It seems like it may have helped a little, but I didn't have time to drive it around and idle it enough to be sure.

I was just looking in my chilton's to see about changing the thermostat... it appears that it is between the block and the metal pipe directly under the throttle body, with the large hose running to the radiator? Am I correct on where it is? If so, I may change that out soon as it looks simple enough to get to.

 

[projectSHO89]

Yep, that's where it is. Piece of cake to replace. Make sure you install the new one with the jiggle valve up and that you don't over-tighten the nuts for the outlet tube.

Steve
89

 

[ret]

cool, looks simple enough to do... 2 bolts and it's off. I'm gonna try and clean the radiator better first though, but the thermostat is next. Any fairly simple way of testing to see if the thermostat is good or not before buying a new one? I know they're cheap, but I'm broke now and tend to screw up even the simplest of installs on cars. Any preferences on which one to get? I was just looking on carparts.com, appears they've got the motorcraft one for $16 and a few others for as cheap as $5.

 

[SHOfun 93]

I just tested my t-stat by removing it and seeing if it would open in a pan of boiling water on the stove. If it didn't open by the boiling point, you know that it is no good. Heck my dad used to check t-stats on all our cars that way for years!

 

[Shoman94]

Jeremy Hohn:
I just tested my t-stat by removing it and seeing if it would open in a pan of boiling water on the stove. If it didn't open by the boiling point, you know that it is no good. Heck my dad used to check t-stats on all our cars that way for years!

Yup thats a good way...I use a temp probe along with it to make sure the t-stat starts to open at the rated temp...ie: 88°c(190.4°f)
May car runs smack dab on M at highway speeds. O-M on city driving. Its normal for the fan to engage between NO. Unfortunately Ford does not sell the 180° t-stat anymore.

 

[pete c]

ret,

sounds lke yer washin' the wrong side of the rad. Crud builds up INSIDE the radiator. So, you can feed the powerwasher enough quarters to buy a new rad and you still won't be cleaning the part that needs it.

 

[SHOfun 93]

Pete, so true...the washer I was referring to is available at autozone or other fine auto parts stores.

 

[AutoSHO]

pete c:
ret,

sounds lke yer washin' the wrong side of the rad. Crud builds up INSIDE the radiator. So, you can feed the powerwasher enough quarters to buy a new rad and you still won't be cleaning the part that needs it.

Uh, actually, no. It does build up in there too, but on the forward face of the radiator (the face out towards the road) it will build up a very nice matting of airflow-blockage. This will cause the car to run warm, especially in hotter temperatures, when you aren't moving as fast.

If you are going to change the thermostat anyways, there's no reason not to rock the radiator back and clean it out. Good Luck!