Ford corsair Running rich and Kmart solution

[aifte2000]

My Ford Corsair 1990 2 lt Auto has been running rich. It blows black smoke under acceleration. Gave it to Kmart- The mechanic tried O2 sensor, ECM code and exhaust system,counldn't fix the prob and  came to a conclusion that the Engine runs too cold because once the fan cuts in it doesn't cut out soon before the Engine is cold. Earlier, the radiator fan of my car stopped working and an autoelectrician installed an external thermostate (fan controller). Kmart mechanic told that it was the autoelectrician who installed the fan controller wrong and thats why the Engine running rich.

 Do you agree with the Kmart Mechanic? Any idea what is going wrong? I have the feeling that the fuel mixture sys never moves into closed loop as there is no apprent change in Engine noise at idle. Leads are ok, engines always turns on, changed spark plugs 6 months back.

Please help. thanks.

[chr1S]

Umm, i remember replacing something with the cooling, a thermostat or something and it didn't run as rich..

but i did a whole lot of other things that day, so im not too sure what it was...

[emuisme]

Has he checked the temp sensor near the timing belt side of the motor (drivers corner?), other thing it could be is the thermostat.

I'd get a second opinion.  I know some people who work at k mart tyre and auto.  I'd let them fix my lawn mower and that would be about the extent of it.

good luck.

[Chadza]

sounds very much like coolant temperature sensor, the ECU one not the gauge one. Should be located near where the top radiator hose goes into the cylinder head.

[aifte2000]

Yeap, I have some serious doubts about the water temperarute sensor. I had a look at the manual for CA20 and all it has is the water temperarure sensor(no seperate coolant sensor) just above the readiator hose connecting to engine manifold. But the mechanic says  if it were the water temperature sensor how could the temperature gauge at the dashborad work alright? The temperature gauge in the instrument cluster seems to show increase/decrease in Engine temperature.

Any answer to that? Thnx 

[JIMB0]

The ECM has a seperate sensor. If the Connection is corroded the ECM will read a higher resistance and think the engine is colder than what it actually is. Try cleaning the connector plug.

[aifte2000]

The workshop manual says- it has only one sensor- water temperature sensor on driver side above the radiator hose connecting to Engine manifold and the sensor sends signal to ECCS.

Anyone with any specefic idea if CA20 has seperate coolant sensor to ECM? Thx 

[emuisme]

after a quick flick through the workshop manual I'd have to agree that it only has one.  perhaps there is a wiring fault?

Why did the fans in your car stop working?

[eurisko]

Although it makes sense, id agree with the others here and wouldnt trust a Kmart Mechanic with installing a windscreen wiper blade...
When i had my other car (1979 Mazda 323) i took it to them for a disk brake machining. After 120 bucks later, and them telling me it was all good, my mechanic mate had a look at their work, they didnt do anything! We took it back to them, they said it was a mistake, they THOUGHT they machined it, but theyll do it there and then at no charge. After 5 mins, they eventually found out that the disk diameter was too small for their machine!! They eventually gave us our money back.


But enough ranting...


If it is just a thermostat problem, buy another one with a smaller range, and test that. Thermostats only cost a few bucks anyways... alot cheaper than going to a mechanic and being told they cant fix it...

Why he couldnt test that... i dunno...

[Jono]

I'm pretty sure there were two temperature sensors on my engine last time I looked.

[emuisme]

ka24 or ca20?  I could only find one temp and one oil pressure switch for the ca20 in the manual - must admit I haven't checked the car.  the ka24 seems to have 1 temp and two oil pressure switches.

I'll try to get a chance to look in the next few days

[eurisko]

I just checked the FSM and there appears to only be one sensor for both the engine and the cluster for the CA20E.

Its located exactly where everyone says, just above the top radiator hose near the thermostat.

But the mechanic says  if it were the water temperature sensor how could the temperature gauge at the dashborad work alright? The temperature gauge in the instrument cluster seems to show increase/decrease in Engine temperature.

Any answer to that? Thnx 

Um, the sensor could be reading a wrong value, either too high or too low... it will still show an increase or decrease in temp... just not the right value.

Unless u got ur own thermocouple to test it... u cant be sure.

Whip out the temp sensor and put it in a pot of water with a glass thermometer. With a multimeter (if you have one) test the resistance at 20 Degrees, 70 and 100 degrees celcious.

Resistance in ohms, should be, 2253, 444 and 188 respectively (with a bit of tolerance accepted). If ur not getting that, get another temp sensor.

[JIMB0]

There are 2 sensors for the Ca20e. They are right near each other. The one for the guage has a simple spade connector (black) and the ECM has a clip on plug (like the injectors, but red). Pull the red plug off and clean it to remove the corrosion.

[Jono]

I just did some under-bonnet spelunking and brought back some photographic evidence:

(This is a CA20E BTW)



The ECM sensor is circled in red, the gauge sensor in green.

[aifte2000]

Thanks Guys. Is there any number or model for ECM temperature sensor? What is the easiest way to make the autoparts shop understand that I need an ECM temperarute sensor for that  particular type? They are not generic for all cars. Are they?

[Chadza]

just tell them what you want and CHECK the part before you take it home. If its the wrong one then say "I'd like the other one please!"

No they are probably not all generic. But it looks like it is similar to the ka24 one. Just different location.

[Jono]

If you tell them you've got a '91 Pintara they should get you the right one.

[JIMB0]

I enquired about that part a while ago, they wanted $70 at trade price. Check it out with your multimeter first before replacing it, at room temp it should be aprox. 2500 ohms. In boiling water it should be aprox. 200 ohms. Also with the ignition on and the sensor disconnected check the voltage across the connector terminals. It should be 4-6 volts.

If it all checks out then give the terminals a good clean and see how you go.