Help with ECT?.....

[Red Baron]

My car has a new (2000 miles on it) radiator, 180F t-stat, upper & lower hoses, no leaks, and a new temp. sending unit (the one that sends the signal to the gauge)...I even reset the computer thinking that it would help, but it did not...the problem is that my gauge goes up to the "O", then the fan kicks on, stays on for 20-25 seconds...I counted....then shuts off...the needle is then at the top of the "R", no lower.

Before I replaced all of the stuff, the gauge would be right in the middle, it would fluctuate, but would not climb to where it is now.

So, do I need to replace the Engine Coolant Temp. Sensor cuz it's bad? Also, there is no leak, (I checked, felt, saw) but I can smell antifreeze, very lightly, coming from the radiator cap...is this normal? Suggestions, please. Thanx.

 

[AutoSHO]

The ECT is only $16.99, and will not harm to replace. Do that first. You might also want to look into replacing the dash gauge sender as well (single wire). In a properly functioning SHO the Fan comes on at the top of the R and goes off at the top of the M.

In a 1995 you should have a 2 speed fan. Perhaps the low speed circuit has failed. Chris (autobahnsho1130) had a similar problem with his '95 SHO. I will ask him to post here.

 

[Red Baron]

I replaced the sensor that has the one wire, but still acts the same. One thing I have noticed is that when the fan comes on, it seems to be on high cuz it's pretty loud. If the low speed circuit has failed, what can be done? Thanx.

 

[AutoSHO]

If the low speed circuit has failed, it could be one of three things: The Computer not sending a signal to the CCRM to activate the low speed fan relay, the Relay in the CCRM is bad, or the low speed circuit has a separate set of brushes in the fan that are bad. I do not know how to troubleshoot that right off hand, but perhaps someone else does. I will try to find a procedure to help.

 

[Red Baron]

Thanx.

 

[Chris Benvie]

I had this problem its Simple enough, replace your CCRM and your Radiator Fan. Make sure the fan is out of a 93-95MTX the prior fans have a different harness.

 

[Red Baron]

AutobahnSHO1130:
I had this problem its Simple enough, replace your CCRM and your Radiator Fan. Make sure the fan is out of a 93-95MTX the prior fans have a different harness.

Is the CCRM the little black box with wires underneath the plastic over the radiator? About 1.5 inches square? How much can I expect to pay for the CCRM and the fan? Is the fan only available through the junkyard? Thanx. thumb

 

[F-22 Raptor SHO]

You might want to check that you dont have an air pocket in your cooling system. this would give you high temp spikes.

May I ask why you replaced the sending unit to begin with? Was it because of the fluctuations?

It sounds like you changed alot of stuff and thus lost alot of coolant. topping the radiator off doesnt mean its full......sometimes it take awhile to get all that air out.

 

[Red Baron]

F-22 Raptor SHO:
You might want to check that you dont have an air pocket in your cooling system. this would give you high temp spikes.

May I ask why you replaced the sending unit to begin with? Was it because of the fluctuations?

It sounds like you changed alot of stuff and thus lost alot of coolant. topping the radiator off doesnt mean its full......sometimes it take awhile to get all that air out.

When I filled up the radiator, I turned on the car and let it warm up until the thermostat opened up then I shut off the car, carefully opened the cap, then put more antifreeze mix in...
The temp. has been reading higher ever since I put in my new radiator (~2000 miles ago) and t-stat....the radiator separated where the plastic and metal meet, causing it to overheat, so I replaced it, only to find out that it originally busted because my t-stat was stuck shut causing it to heat up and bust....

I changed the sending unit in case it was the problem...it only cost 4.99, so I figured what the heck, why not...

I noticed that when I run the A/C compressor, the fan turns on high and stays on...normal...but when I'm just idling the car w/o the compressor, the fan turns on high when it hits the "O", then turns off when it hits right above the "R" and it stays on for only 20-25 seconds....at no point did the fan spin at a lower speed...sooooo....

What does this point to? Fan motor? CCRM? ECT Sensor? shrug Sorry for the long post and thanx...

<small>[ February 19, 2004, 06:08 PM: Message edited by: redmase ]</small>

 

[Rockledge]

I might be missing something here, but it doesn't seem to me that your cooling system is operating that far out of whack, if at all. If the fan is kicking on and keeping the motor from overheating, then it's doing what it's supposed to do. shrug

The fact that the needle on your dash gauge is riding a little higher than before, and now hovers around the "R", is not a significant event IMO, especially since we will never know what the actual temperature of the coolant was when the fan used to come on, and we don't know what that temperature of the coolant is now (do we?), so there is nothing firm to go by that would tell us for sure that things are not working the same as they used to.

FWIW, right after I replaced the radiator in my SHO a few months ago, my ECT failed, and my fan would not even come on at all. New ECT = problem fixed.

 

[snake396]

it was my understanding that MTX's have only single speed fans, not the two speed fans that the ATX's get.

 

[AutoSHO]

snake396:
it was my understanding that MTX's have only single speed fans, not the two speed fans that the ATX's get.

The 95 MTX has a 2-speed fan. Not sure about the 93-94. The ATX has a 2-fan setup, not a 2 speed single fan.

 

[SHOZ123]

A 180F t-stat will only help on the highway and when cool. The t-stat is a minimum temperature maintainer. It cannot help keep the car cooler than 180F. With the fan coming on at O and turning on at R this means your ECT and gage are both reading accurately. O is around 215F and the R is around 200F. This is exactly the factory specs for the V6 SHO. Does it run between the A and M on the highway? If you want the engine to run cooler you will have to add something that will turn the fans on sooner.

<small>[ February 19, 2004, 07:45 PM: Message edited by: SHOZ123 ]</small>

 

[Red Baron]

Rockledge:
I might be missing something here, but it doesn't seem to me that your cooling system is operating that far out of whack, if at all. If the fan is kicking on and keeping the motor from overheating, then it's doing what it's supposed to do. shrug

The fact that the needle on your dash gauge is riding a little higher than before, and now hovers around the "R", is not a significant event IMO, especially since we will never know what the actual temperature of the coolant was when the fan used to come on, and we don't know what that temperature of the coolant is now (do we?), so there is nothing firm to go by that would tell us for sure that things are not working the same as they used to.

FWIW, right after I replaced the radiator in my SHO a few months ago, my ECT failed, and my fan would not even come on at all. New ECT = problem fixed.

I took the temp a few weeks back and the needle was a tiny bit above the "R", but still on it, and the temp. reading was 213F, and no fan...

From what I have read through doing searches, the fan should turn on low at 215F and off at 210F, and on the MTX, turns on high at 230F and off at 224F...

I monitored my fan and it turned on HIGH when the gauge hit the "O" and turned off when it hit right above the "R", which was for less than 20 seconds this time. squint It never turned on low speed, just went to high speed then turned off. squint squint According to information on this forum, the "O" is 220F and the "R" is 200F, approx.

Soooo...since it does not turn the fan on low and just jumps from high to off, does this indicate the motor? CCRM? ECT? Thanx for all the help.

 

[SHOZ123]

If the '95 has a three wires going to it, it has a two speed fan. It does sound like your low speed is not working. It is feed through a dropping resistor that lowers the voltage and hence the slower speed but still goes through a relay in the CCRM. You should see if there is power at the fan when the temp is around 215F.

<small>[ February 19, 2004, 07:59 PM: Message edited by: SHOZ123 ]</small>

 

[Red Baron]

SHOZ123:
If the '95 has a three wires going to it, it has a two speed fan. It does sound like your low speed is not working. It is feed through a dropping resistor that lowers the voltage and hence the slower speed but still goes through a relay in the CCRM. You should see if there is power at the fan when the temp is around 215F.

How do I check to see if there is power to the fan? And can the slight smell (not leaking) of antifreeze coming from the radiator cap have anything to do with it?

<small>[ February 19, 2004, 08:29 PM: Message edited by: redmase ]</small>

 

[Mr Anonymous]

A multimeter can be used to test the fan and CCRM ckt's.

You might want to start with a simple, good-'ol-fashioned reading of the codes. That might just point you right at any problem(s) that may exist. It will also test BOTH speeds of the fan for you.

Next step might be to get a IR thermometer to determine the actual temps where the fan is coming on and shutting off. The gauge sender is not a precision instrument as mentioned, and often no two will give the same reading. The gauge sender that you replaced controls only the gauge. The ECT sensor tells the PCM the temp in order to control open/closed loop modes, fan activation, etc.

Your gauge temps seem perfectly normal to me, especially in the mid-60 deg. weather you're probably enjoying in El Paso. If you're really bothered by it, go ahead and replace the ECT sensor and see if that makes it appear better. Under $20 for peace of mind is often a good investment IMHO.

 

[Red Baron]

I will run the codes tomorrow and see what it spits out....also, to see if both fans are working...if the low fan speed does not work, what would that be an indicator of? If it does work? Thanks for all the help, everybody.... beer

 

[SHOZ123]

You won't find any code that tells you the fan is not working. Does your fan have three wires going to it? If so, disconnect the plug going to it and start the engine with the A/C on, there should be 12V on one of the wires. Another wire will have 12V when the temp rises higher and the high speed should be on.

 

[DHMag]

its known that Ford temp gauges arent the most accurate pieces of equipment out there. Ford is in the business of making cars, not quality temp gauges.

as for t-stats, not all are made the same. i guarantee that if you buy 2 off the shelf, theyll both vary in operating temperature performance.

the CCRM is not the little square box, thats the air bag trigger sensor. the CCRM is under the radiator panel, to the right. black, about 5"x"6". you can open it up and replace just the relay, or replace the whole box, if you feel so inclined.

when i replaced my radiator and t-stat, normal temp readings went from the O-R range down to the L range. this is case in point about t-stats and gauges.

now that i have an actual water temp gauge, i can tell exactly when my fan comes on and when it will shut off. i added Water Wetter to my cooling system and it actually raised the normal temp. so....at 222*, fan comes on, shuts off at 212*. before the Water Wetter, i was running constant 190* temps on the highway. a lot will disagree with me, but your cooling system mixture also has a lot to do with your temperatures.