I have a 2001 Saturn L300

Try this what if you let up on the gas pedal a little will it then shift from second to 3rd?

The p0102 is mass air flow sensor low frequency the code P0116 is engine coolant temperture sensor performance The two codes are probably related since that code can set from two great of a temp reading difference from the ambient temp sensor located in the mass air flow sensor. You will need a scan tool that can read live mass air flow and coolant temp sensor data. See if the mass air flow sensor harness is damaged chewed etc?

You should be able to rent or borrow one from Autozone, Advanced Auto, or O'Reilly's. Usually they will want to take a hold a credit card or your ID if you're going to work on it in the parking lot.

Did the shifter move? Check the linkage t make sure it's all tight. The MAF COULD cause stalling, yes.

Check the linkage and check the fluid level.

Yes. The gear shift linkage.

1. Start engine and operate vehicle until transaxle fluid temperature reaches at least 104°F (40°C). Depress brake pedal and move shift lever through all gear ranges, pausing a few seconds in each range. Return shift lever to Park range. For vehicles equipped with 2.2L engine, go to next step. For vehicles equipped with 3.0L engine, go to step 3.
2. Remove clamp from A.I.R. Hose behind cooling fan. Separate A.I.R. Tube from hose and push tube back toward transaxle. See Fig 1. Note original position of A.I.R. Components. Remove power steering hose clip (1) holding 2 power steering lines together. See Fig 2.
3. Raise vehicle. Vehicle must be level, with engine running. Remove transaxle oil level plug. See Fig 3. Check fluid level. Transmission fluid level should be even with bottom of threaded plug hole. Check condition of transaxle fluid. See FLUID DIAGNOSIS .
4. If fluid level is low, add DEXRON-III ATF in increments of 0.5 Qt. Until fluid drains from plug hole. If more than 1.6 Qts. Of fluid needs to be added to transaxle, transaxle may have a leak.

Rapid fluctuation in line pressure could set DTC P0742. Check for pressure regulator malfunction and low or high line pressure. Inspect wiring for poor connections at TCM and at transaxle 20-pin connector. Check for bent, backed out, deformed or damaged terminals. Check for weak terminal tension. Check for chafed wire that could short to bare metal or other wiring. Inspect for broken wire inside insulation. Customer may notice an engine stalling condition. If diagnosing for intermittent short or open condition, manipulate wiring harness while observing scan tool for value change. Inspect and repair the following items:
†Restricted TCC solenoid exhaust.
†Plugged TCC solenoid filter.
†TCC control valve stuck in released position.
†TCC regulated apply valve stuck in released position.
†Stuck TCC feed limit valve.
†Stuck pressure regulator valve.
†Leaking TCC fluid circuit.
†Damaged or leaking TCC release switch.

P0102
Mass Airflow (MAF) sensor measures speed and density of air entering intake manifold. ECM converts this input to a mass of air per unit time to correctly fuel engine. MAF output voltage is a function of power required to keep sensing element at fixed temperature greater than outside air temperature as incoming air cools sensing elements. Output voltage varies between 0.14 and 4.8 volts under all normal engine running conditions. DTC sets when MAF sensor signal voltage at ECM is less than calibrated voltage value.

Code Enable Criteria

†Engine is running for more than 0.3 second.
†Ignition voltage is more than 11 volts.
†No TP sensor DTC is set.

DTC sets when MAF sensor voltage is less than 0.14 volt (less than zero grams per second).

Diagnostic Aids

To locate an intermittent problem, use scan tool to monitor MAF SENSOR with ignition on, engine off. Wiggling wires while watching for a change in MAF SENSOR voltage may locate area where an open or short to ground in wiring could lie.

If ECM looses MAF sensor signal, it will calculate airflow based on engine speed and TP sensors.

If DTCs P0102, P0107, P0341 and P0405 are set, 5-volt reference circuit may be open.

P0116

Engine Coolant Temperature (ECT) sensor is a thermistor that varies resistance according to changes in engine coolant temperature. ECM supplies a 5-volt reference through a pull-up resistor(s) to sensor, which is connected to ground. When sensor is cold it has a high resistance (high signal voltage at ECM). As sensor temperature increases, its resistance decreases (low signal voltage at ECM). ECM uses signal voltage to determine engine coolant temperature. ECM calculates a modeled temperature using start up ECT, MAF, MAP and engine run time and compares this value to ECT sensor signal. DTC sets when ECT deviates more than a calibrated value from ECT modeled temperature.

Code Enable Criteria

†Engine is cranking or running.

DTC sets when ECT sensor signal deviates more than 22°F (12°C) from ECM modeled temperature.

Diagnostic Aids

DTC indicates that ECT sensor readings are valid, but deviate more than 12°F (12°C) from ECM modeled temperature.

Possible causes:
†Skewed sensor.
†Very low or very high ambient temperatures.
†Corrosion in connector or resistance in wiring.
†Poor connections in ECT circuit.
†Thermostat malfunction.
†Cooling fan(s) malfunction.

ECT sensor reading may be compared to IAT sensor reading on scan tool after vehicle has been sitting more than 6 hours with ignition off. Both readings should be within 10°F (6°C) of each other.

P1780

Engine Control Module (ECM), Body Control Module (BCM) and TCM communicate with each other via the Controller Area Network (CAN) bus circuits. TCM ensures CAN messages are being received by checking the BUS failure timer. DTC P1780 will set if TCM did not receive needed engine parameter over CAN BUS from ECM.

Description

DTC indicates that ECM received a message from TCM to turn on MIL telltale due to a transmission related OBD II failure. ECM will send a message via CAN link to BCM, which will send a message over Class II link to instrument panel cluster to turn on MIL.

Code Enable Criteria

DTC sets when ECM receives a MIL request message from TCM over CAN link.

Conditions For Setting DTC

DTC will set under the following conditions:
†System voltage is 8-18 volts.
†Condition exists for 2 seconds.

Diagnostic Aids [ DTC P1780: TORQUE REDUCTION SIGNAL ]

Check for any related DTCs in the ECM and Electronic Brake Traction Control Module (EBTCM). Diagnose any stored DTCs.

Diagnostic Aids [ DTC P1780: MIL EXTERNAL REQUEST BY TCM ]

DTC does not indicate a fault with CAN link circuit.

P1818

Circuit Description

See DTC P1810: TRANSMISSION FLUID PRESSURE SWITCH CIRCUIT .

Conditions For Setting DTC

DTC will set under the following conditions:
†TFP switches indicate D4, D3, D2 and D1 when the gear ratio indicates Reverse

P1810

NOTE: Transmission Fluid Pressure (TFP) switch assembly may also be known as Transaxle Pressure Switch Assembly (PSA).

Circuit Description

Transmission Fluid Pressure (TFP) switch consists of 6 pressure switches. One switch is normally closed, and is used to detect TCC release fluid pressure. Other switches are normally open, and are used for determining gear range selection. TFP switch assembly contains Transmission Fluid Temperature (TFT) sensor. These components are combined into one unit and mounted on control valve body.

TCM provides battery voltage on each range signal. By grounding one or more switches with fluid pressure from manual shift valve, TCM detects selected gear range. When transaxle electrical connector is disconnected and ignition is on, ground potential for 3 range signals from TCM will be removed, and an illegal gear will be indicated. See TFP SWITCH LOGIC table under DESCRIPTION & OPERATION. DTC P1810 will set when TCM detects an invalid gear status, a drive range after start-up or an incorrect gear ratio.

Conditions For Setting DTC

If TCM detects any of the following states, DTC will set in required conditions:
†Gear range is illegal for 60 seconds. See TFP SWITCH LOGIC table under DESCRIPTION & OPERATION.
†Engine is running.

Diagnostic Aids

A pressure regulator malfunction could set DTC P1810. Inspect wiring for poor connections at TCM and at transaxle 20-pin connector. Check for bent, backed out, deformed or damaged terminals. Check for weak terminal tension. Check for chafed wire that could short to bare metal or other wiring. Inspect for broken wire inside insulation. If diagnosing for intermittent short or open condition, manipulate wiring harness while observing scan tool for value change.

I dont know why the mitchel ondemand says dex3 that trans takes dex4 and up. As far as the fluid level goes unless there is a leak I wouldnt worry about the fluid level. Also for the the codes P0102 and P0116 I would check and compare the inlet air temp verus the coolant temp on the scan tool when the car has sat over night and is completely cold. Thats where I would start with codes. As far as the P0742 and the P1818 for the P1818 you would use the P1810 trouble tree. Which requires a scan tool that can read live transmission data. Which you could used for 200-300 that would also do live data for the engine also.I posted the trouble for the code P1810 so you can get an idea of what iam talking about.

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Sorry was thinking of a different saturn it takes dex 3;