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90turbo1
08-26-2013, 01:32 PM
so I finally got my t-bird through emissions. and now I can drive it. my problem is it runs very very warm. I am talking upwards of the needle almost to the right side of the "NORM" marks on the stock guage.

It seems the fans do not come on, I have the spoiler installed under the rad support like it was from factory, new aluminum radiator, new water pump and all hoses are new. I bleieve there are no air pockets in the cooling system as far as I can tell.

I can acitvate the fans using my scan tool on both speeds, but I am not sure if the temp guage is accurate (probably not) but the car just seems to run very very hot.

oh yeah stock tune, stock t-stat setting, everything is stock, except for underdrive pulley.

i have my doubts about the stock exhaust being partially plugged, its on the list of things I need to change yet.

any ideas?

XR7 Dave
08-26-2013, 01:47 PM
Stock setting for the fan to come on is 220 deg which is pretty hot. I can program a chip for you that brings the fans on earlier, with a stock thermostat I generally set it at 200 deg which makes a big difference.

The gauges are not all that accurate and vary widely from car to car.

Check operating temps with your scanner and see what is going on first.

90turbo1
08-26-2013, 01:53 PM
Stock setting for the fan to come on is 220 deg which is pretty hot. I can program a chip for you that brings the fans on earlier, with a stock thermostat I generally set it at 200 deg which makes a big difference.

The gauges are not all that accurate and vary widely from car to car.

Check operating temps with your scanner and see what is going on first.

THANKS, I WILL CHECK THAT TOMORROW WHILE i DRIVE IT IF i CAN GET THE CABLES INTO INTERIOR TO LOOK AT SCANNER. HOW MUCH WOULD THIS CHIP RUN ME.

XR7 Dave
08-26-2013, 01:59 PM
THANKS, I WILL CHECK THAT TOMORROW WHILE i DRIVE IT IF i CAN GET THE CABLES INTO INTERIOR TO LOOK AT SCANNER. HOW MUCH WOULD THIS CHIP RUN ME.

Chip is $250 and carries a full money back satisfaction guarantee.

90turbo1
08-26-2013, 02:02 PM
Chip is $250 and carries a full money back satisfaction guarantee.

awesome, what else do you tweek in there?

I am only wanting the hot engine thing fixed and remember I have a 5percent blower pulley. plan on doing the better cats and downpipes soon now that I am driving it.

I will get you some numbers off my scan tool tomorrow when I drive it to work.

bumpskier45
08-27-2013, 07:15 AM
you can get dave to do more than just the temp on that chip by the way so if your thinking of any upgrades you could add those to your tune. Dave did mine about 5 months I had same problem you did,now it stays dead center all the time,I would get the tune done....problem solved.

Jacob_Royer
08-27-2013, 07:57 AM
180f t-stat and a chip you will run even cooler! Hottest my car will get now with ac on mid 90s outside is 204f and will stay in the 190s i f I'm nice to it!

90turbo1
08-27-2013, 12:08 PM
yeah I think I will bite the bullet and get it done. If anything it can only help the head gasket problems these cars have it seems.

i just need to wait till my next paycheck though, you know ballin on a budget here...

ha ha

bumpskier45
08-27-2013, 12:19 PM
agreed,that is what I run in mine is 180 degree,if your getting a tune done that is what most folks on here will recommend. If your going to change out the t-stat to the 180 degree one I would get in touch with bill at supercoupe performance,most of your local parts stores won't have what your looking for and bill has a pretty sweet one with the correct gasket for a decent price,problably more money than you would expect to pay for that item but believe me well worth it,my chip has been in there for 5 months and its awsome. Not sure I mentioned it but dave did the tune,and everything turned out perfect.

TbirdSCFan
08-29-2013, 10:48 PM
As FYI. If you study the EEC 4 circuitry (http://www.kvitek.com/ford/), you can see that the EEC fully controls the fan and that if the fan is late on a computer which was working correctly, then the A/D circuitry the ECU needs to measure ECT sensor voltage drop is failing. In more simpilfied terms, its not the computer chip itself, but some other circuit on the board.
So while getting a EEC assembly with a reprogrammed ROM chip will certainly fix the problem.. so also will a new or refurbd EEC. For a fan problem, its overkill. :rolleyes:

You really only need a reprogrammed/tuned EEC if you're making power and want to tweak the running parameters to best use your mods. Oh, and by the way, it can turn the fan on sooner when everything else is working correctly.

Im a little surprised that nobody mentioned any of this. :confused:

S_Mazza
08-30-2013, 01:19 PM
As FYI. If you study the EEC 4 circuitry (http://www.kvitek.com/ford/), you can see that the EEC fully controls the fan and that if the fan is late on a computer which was working correctly, then the A/D circuitry the ECU needs to measure ECT sensor voltage drop is failing. In more simpilfied terms, its not the computer chip itself, but some other circuit on the board.
So while getting a EEC assembly with a reprogrammed ROM chip will certainly fix the problem.. so also will a new or refurbd EEC. For a fan problem, its overkill. :rolleyes:

You really only need a reprogrammed/tuned EEC if you're making power and want to tweak the running parameters to best use your mods. Oh, and by the way, it can turn the fan on sooner when everything else is working correctly.

Im a little surprised that nobody mentioned any of this. :confused:

Everyone was waiting for the OP to actually verify the temperature his car runs at, but the information never came.

Additionally, you seem to be way ahead of the curve in understanding of this A/D converter issue. I have never heard of it anywhere else but your posts. So I don't think it's a common problem (at least not yet). There are certainly variations between Ford EECs, and some of them have more problems than others. I know that Mustang and some Bronco EECs have problems with bad capacitors and burned circuit traces. But they seem to be quite rare on our EECs.

P.S. - Thanks for the link. :)

P.P.S. - I read through some of the links. From what I can tell, the A/D converter is integral to the 8061 microcontroller. The brains of the operation. It looks like the A/D has 13 dedicated inputs, and each input corresponds to one of the pins on the chip. This means that you could conceivably trace the circuit from the EEC connector plug to the solder pad and to the chip pin. If there is a problem with the circuit, you should be able to find it. This assumes that the circuit trace is visible and doesn't play hide & seek in multiple layers of PCB. Also, I believe that the A/D converter needs a battery voltage reference. And some of the inputs may go through voltage dividers to make sure the input ends up in an acceptable range for the A/D converter.

Here is a sample of the Intel application notes for the related 8096 chip that shows what you might find on an input line:

3.2.4. USING THE A TO D
The code in Listing 3-12 makes use of the software flags to implement a non-interrupt driven routine which scans A to D channels 0 through 3 and stores them as words in RAM. An interrupt driven routine is shown in section 4.1. When using the A to D it is important to always read the value using the byte read commands, and to give the converter 8 state times to start converting before reading the status bit. Since there is no sample and hold on the A to D converter it may be desirable to use an RC filter on each input. A 100X resistor in series with a 0.22 uf capacitor to ground has been used successfully in the lab. This circuit gives a time constant of around 22 microseconds which should be long enough to get rid of most noise, without overly slowing the A to D response time.

I also came across this on EECTuning.org:

...MAFs do have the ability to report above 5v, but the EEC is the limiting factor with its A/D converter being unable to accept voltages above 5v...5.12v to be exact.

And here is something from Corral.net about temperature inputs:

I deal with later model cars, this is from FMCDealer also, 2002 Mustang PC/ED file :
Intake Air Temperature Sensor
The intake air temperature (IAT) sensors (Figure 33) and integrated MAF type (Figure 36), are thermistor devices in which resistance changes with temperature. The electrical resistance of a thermistor decreases as the temperature increases, and increases as the temperature decreases. The varying resistance affects the voltage drop across the sensor terminals and provides electrical signals to the PCM corresponding to temperature.

Thermistor-type sensors are considered passive sensors. A passive sensor is connected to a voltage divider network so that varying the resistance of the passive sensor causes a variation in total current flow.

Voltage that is dropped across a fixed resistor in a series with the sensor resistor determines the voltage signal at the PCM. This voltage signal is equal to the reference voltage minus the voltage drop across the fixed resistor.

The IAT provides air temperature information to the PCM. The PCM uses the air temperature information as a correction factor in the calculation of fuel, spark and MAF.

The IAT sensor provides a quicker temperature change response time than the ECT or CHT sensor.

Supercharged vehicles use (2) IAT sensors. Both sensors are thermistor type devices and operate as described above. However, one is located before the supercharger at the air cleaner for standard OBD II/cold weather input, while a second sensor (IAT2) is located after the supercharger in the intake manifold. The IAT2 sensor located after the supercharger provides air temperature information to the PCM to control border-line spark and to help determine intercooler efficiency.

Currently two types of IAT2 sensors are used. A screw in type (Figure 33) and an integrated type, witch is part of the Thermal Manifold Absolute Pressure (TMAP) sensor (Figure 40). The TMAP sensor consists of a IAT thermistor and a manifold absolute pressure (MAP) sensor. The thermistor portion of the TMAP is used for IAT2 function and operates in the same manner as a non-integrated IAT2. For additional information on the MAP portion of the TMAP, refer to the Thermal Manifold Absolute Pressure Sensor description and operation found later in this Section.

So I would think that, if the readings from only one sensor are not working properly, and everything checks out from the sensor to the EEC connector, then one of the input filter / comparison features must be bad. A resistor or capacitor, most likely.

TbirdSCFan
08-31-2013, 03:56 PM
Heres an actual schematic. At least the best I could locate.. Note the ECT, ACT, TP all feed into a single interface chip before the 8061 sees the signal. I have not been able to identify it on the EEC board itself. Each line has its own filtering cap, but that's not going to affect the voltage level. If the reference 5v is wrong, that might explain the problem. Can anyone identify what a 1/2 of NY30 is? Anyone have a better schematic?

S_Mazza
08-31-2013, 11:29 PM
Nice schematic. Is that for our cars specifically?

Maybe that 1/2NY30 is a voltage divider? To drop the 5V input to a lower level for the 8061 chip? It looks like it has up to 14 pins, and there is more than one similar unit on the board.

A bad 5V reference could certainly cause problems.

If the filtering cap went bad (partial short), might that drop current available on that circuit? Maybe there is a certain threshold below which it can't excite the appropriate circuit in the 8061? Just a thought.

RalphP
09-01-2013, 12:47 AM
NY30 should be the location on the board, using the references across two of the four sides (or maybe across all four sides, depending on how they did it.)

No, got no idea what it is - that schematic tells me nothing as to what goes on inside it.

RwP

rickbtbird
09-01-2013, 03:26 AM
I am talking upwards of the needle almost to the right side of the "NORM" marks on the stock guage.

any ideas?

In the summer time, my 95 has been running that way for the entire time I've owned it. Once it hits above the M, the fan comes on and cools things down.

XR7 Dave
09-01-2013, 09:26 AM
The discussion on ECT sensor circuitry is interesting but you guys are putting the cart way before the horse without knowing what temperature the engines are actually running at. The gauges are very unreliable indicators of what actual temperature is. Verifying the existence of an actual error would seem to be the first step, not the last.

I tend to be a little more old fashioned in my testing and diagnosis procedures. I start by observing the ambient temp readings coming from both the ACT and ECT sensors in the morning after the car has sat all night. Comparing them to each other and to the thermometer outside will give me a pretty good indication of whether there is a problem. Then watching the temperature climb as the car runs until the thermostat begins to open is the next one. If you have a 180 deg thermostat then temperature will level off for a few seconds at that temperature and then resume climbing until the fan kicks on after which you can watch temperature climb and fall in a rhythmic pattern as the fan cycles through it's on/off temperature settings.

But that's me and I'm old fashioned.