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Sounds as though your mixture is incredibly rich. One way for this to happen is a malfunctioning ECU coolant temp sensor (the second one back on the intake manifold side of the engine). See the FAQ for a resistance test on this device:
Diagnosing ECT Failures. [Response: Don Foster, adapted to 700/900 series by Editor] Your engine has two temp sensors -- one for the gauge (it's mounted in the head about under intake header #2, and one for the FI (it's mounted in the head about under intake header #3). The latter is the ECT sensor.
The sensor is an NTC thermistor -- negative temperature coefficient. As the temp drops, the resistance rises, and as the temperature rises, the temperature drops. Thus, if you have a broken wire, defective sensor, or bad connection (I've seen it happen) the resistance measured by the ecu will be very high or infinite. The ECU interprets this as minus a zillion degrees and pours in the gas.
The car I saw filled the oil with gas and certainly wouldn't run. And the problem was only a displaced spade lug in the plastic connector
housing.
According to Chilton's (you may choose to disregard this):
"The coolant temperature signal to the control unit has a great influence on the computed injection period... For example, when the engine is
being started and is cold, the amount of injected fuel must be relatively large. [Editor:] Too rich a mixture because of a failing ECT may
lead to idle surges, high idle, poor warm running, or other symptoms of too much fuel. See Engine Tune and Performance; Symptoms for
more examples.
"If the control unit receives a signal higher than 302F (150C) or lower than -40F (-40C), it will interpret the signal as a fault...the control unit
will assume a substitute value corresponding to 32F (0C) on starting and 68F (20C) when the engine has started.
"With the control unit connected, connect a voltmeter across LH ECU terminals 13 and 5 (ground), turn the ignition switch ON.
At 68F (20C) the voltage should be 2.0 +/-.5v volts.
At 104F(40C) the voltage should be 1.2 +/- .3volts
At 176F (80C) the voltage should be .5 +/- .2volts.
The resistance values between pins 13 and 5 or between pins on the sensor are (by eye from the chart):
32F (0C)-- about 6000 ohms within a range of +/- 10%
68F(20C) -- about 2300 ohms "
104F(40C) -- about 1300 ohms "
140F(60C) -- about 600 ohms "
176F(80C) -- about 300 ohms "
212F -- about 190 ohms "
[Response 2: Steve Ringlee] ECT resistance "cold" should be around 6k ohms at 32 degrees F (0 deg C), 2300 at 68 degrees F (20 C),and 200 at 212 F (100 C). However, try checking your ECT wiring: Between pins 13 and 5 at the LH ECU (with sensor DISconnected) resistance should be infinite. Voltage with the ignition ON and sensor connected, measured between pins 13 and 5, should be:
0 C=around 3 volts +/-.5v
20C=around 2 volts +/- .5v
100C=around .3 volt +/- .1v
If these aren't correct, check the connections in the ECT wiring harness. Check engine ground connections at the intake manifold. If the voltage is zero, your ECU is at fault.
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