EEC Codes again...

[Tiggie]

How is everyone? Sorry I haven't been around, dial up won't load anything in the amount of free time I've had recently.

Pulled codes on the '88 today. Surprisingly, got only three codes (down from the 8 or so I had several months ago).
For the KOEO test:
- Code 34 - Insufficient EGR flow/Excessive exhaust back pressure; or EVP voltage above closed limit(SONIC)/PFE sensor voltage high or out of range. (WTF does that mean?)
- Code 51 - ECT sensor fault or open circuit

For the KOER test:
- Code 98 - Computer detected hard fault (EEC in FMEM or Failure Management Effects Mode)

I'm gonna check out the ECT sensor and swap in a spare. I'm open to suggestions on 34 and 98 (which kind of worries me).

Also, pulled the codes on my mom's '87 5.0 Turdbird which has developed a engine missing problem during warm up. Got code 42 - Oxygen Sensor indicating system rich, right side. Oxygen sensor problem?

[gadget73]

34 is probably a chunk under the egr valve hanging it open, or the sensor is bad.

51, make sure the sensor is plugged in, and the wires aren't broke. an ohm meter will tell you if the sensor itself is shot or not without swapping it. If you get some reading, its not open.

98, absolutely no idea



on the turd, 42 is probably not an o2 problem. it probably actually is running too rich. check for vacuum leaks or a leaky injector on that side. should be able to tell by reading the plugs.

[Tiggie]

Swapped ECT sensors on the '88. No change, same codes. Just for kicks, I got out the test light. No voltage on either prong in the ECT connector (is there supposed to be?).

Tried the EEC "Wiggle" test. Somewhere there is a contant fault in some circuit. Hmmm... that helped.

Just to get this straight - the ECT sensor is the sensor the ECM uses for the engine coolent temperature and it is located on the "adaptor" coming out of the intake manifold to a heater hose. It has one connector with two wires in it. The engine temperature sensor is what the engine light uses and it screws directly into the intake manifold on the front, towards the left. It has one wire connector. Is this correct?

[Tiggie]

Thanks Gadget. I'll check the ECT sensor with an ohm meter just to make sure it is okay.

[Tiggie]

No reading with the ohm meter on either ECT (one obviously not installed in the car).

I thought for a minute that maybe the ECT connector got swapped with the similar connector that runs over to the carbon canister solenoid. Checked and they are not swapped. BK and GN/BK wires for the ECT and two BK's for the carbon canister solenoid.

If I get to feeling froggy, I may swap over a low mileage EGR assembly I got from the junkyard, or at least investigate my current one.

[gadget73]

it should give you a reading across the 2 pins on the sensor. You should also be able to get about 5v from ground to one of those pins, and something around 1v from ground to the other pin. this on the one in the car with the ignition turned on of course.

[Tiggie]

I'm getting about 2.5V from the green wire and nothing from the black wire.

So between the two pins on the sensor, I should be getting an ohm reading?

[gadget73]

should, yes. It'll be in thousands of ohms, so you might have to change the range on the meter to get something.

here's the temperature to ohms and volts chart

http://fordfuelinjection.com/index.php?p=28

[gabegt90]

Swapped ECT sensors on the '88. No change, same codes. Just for kicks, I got out the test light. No voltage on either prong in the ECT connector (is there supposed to be?).

Tried the EEC "Wiggle" test. Somewhere there is a contant fault in some circuit. Hmmm... that helped.

Just to get this straight - the ECT sensor is the sensor the ECM uses for the engine coolent temperature and it is located on the "adaptor" coming out of the intake manifold to a heater hose. It has one connector with two wires in it. The engine temperature sensor is what the engine light uses and it screws directly into the intake manifold on the front, towards the left. It has one wire connector. Is this correct?

are you measuring the resistance of the ect sensor? Yeah you are correct the ect is in the adapter for the heater hose.

[Tiggie]

here's the temperature to ohms and volts chart

http://fordfuelinjection.com/index.php?p=28

Voltage appears to be in spec.

I'm getting absolutely no resistance between the two pins on the ECT sensor.

[gadget73]

wierd, i dunno mang, if it gives the proper voltage reading, the sensor can't be totally fubar. If it was, it wouldn't be giving you any output, or it would be like 5v or something. i've never actually stuck an ohm meter on mine, perhaps they don't actually read

[Tiggie]

Could be my cheapo ohm meter too.

Whatever the codes mean, I got 21MPG on my trip yesterday so it can't be too bad.

It was acting funny though. It would go a few miles and be fine and then it acted like someone floored it (except for no upshift and no accelerator movement) for a few seconds, then back to normal.

I asked my dad about the plugs in the T-Bird. He said they were clean when he changed them when he changed them about 1000 miles ago (it was doing the missing thing before this as well). The car shows no signs of a vacuum leak. Would it make a difference if I told you the car was still running the original O2 sensors at 218K miles?

[gadget73]

oh boy. you know those start to become out of whack by around 75k right?