Cranks but won't start

Have you checked the fuel pressure at the engine? This is critical. While there can be other causes such as a faulty ignition module, I would first be very sure the fuel pump and regulator are doing their jobs properly, and there are no restrictions in your fuel lines..

hi, i would like to advice you check the electronic idle speed control valve and also check engine coolant temp sensor. The ISC (idle speed control valve) is located somewhere below the throttle valve. the engine coolant temp sensor is located near distributor. it has a two wire connection. the sensor connector is usually green

This problem can be hard to track down , it could be caused by several thing's ! A bad check valve in the fuel pump letting fuel drain back into the tank , not keeping fuel line pressure up , a crankshaft position sensor can also cause this as well as an ignition control module !
Checks
Action
DEFINITION: Engine cranks OK, but does not start for a long time. Does eventually run, or may start but immediately dies.
Preliminary
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Refer to Important Preliminary Checks Before Starting in Symptoms - Engine Controls .

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Inspect the powertrain control module (PCM) grounds for being clean, tight, and in the proper locations. Refer to Engine Controls Schematics .

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Search for bulletins.

Sensor/System
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Test the engine coolant temperature (ECT) sensor for being shifted in value. Connect a scan tool. Compare the engine coolant temperature against the intake air temperature (IAT) on a cold engine. The ECT and IAT sensor values should be within ?± 3?°C (5?°F) of each other. If the ECT sensor is out of range with the IAT sensor, check the resistance of the ECT sensor. Refer to Temperature Versus Resistance for resistance specifications. Replace the ECT sensor if the resistance is not within the specification. If the sensor is within the specification, repair the ECT signal circuit for high resistance.

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Inspect the mass air flow (MAF) sensor installation. A MAF sensor that is incorrectly installed may cause a hard start. Important: The embossed arrows on the MAF sensor indicate the direction of the intake air flow. The arrows must point toward the engine. Install the MAF in the proper direction. Refer to Mass Airflow Sensor/Intake Air Temperature Sensor Replacement .

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Inspect the camshaft position (CMP) sensor for proper mounting and/or a bad connection. A long crank time occurs if the PCM does not receive a CMP signal.

Fuel System
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Inspect the fuel pump relay operation. The fuel pump should turn ON for 2 seconds when you turn ON the ignition. Refer to Fuel Pump Electrical Circuit Diagnosis .

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A faulty in-tank fuel pump check valve allows the fuel in the lines to drain back to the tank after the engine stops. Refer to Fuel System Diagnosis .

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Inspect both injector fuses for being open. An open injector fuse causes four injectors and four ignition coils not to operate. Replace the fuse. Inspect the injector circuits and the ignition coil circuits for an intermittent short to ground.

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Inspect for incorrect fuel pressure. Refer to Fuel System Diagnosis .

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Inspect for a restricted fuel filter. Refer to Fuel System Diagnosis .

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Inspect for a contaminated fuel condition. Refer to Alcohol/Contaminants-in-Fuel Diagnosis .

Ignition System
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Test both injector fuses for being open. An open injector fuse causes four ignition coils and four injectors not to operate. Replace the fuse. Inspect the ignition coil circuits and the injector circuits for an intermittent short to ground.

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Inspect for proper ignition voltage output with J 26792 Spark Tester. Refer to Electronic Ignition (EI) System Diagnosis .

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Remove the spark plugs and check for the following:

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Correct heat range

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Wet plugs

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Cracks

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Wear

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Improper gap

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Burned electrodes

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Heavy deposits

Refer to Spark Plug Inspection in Engine Electrical.
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Determine the cause of the fouling before replacing the spark plugs if the spark plugs are gas, coolant, or oil fouled. Refer to DTC P0172 or P0175 for diagnosis of the rich condition. Refer to Spark Plug Inspection in Engine Electrical for diagnosis of coolant or oil fouled spark plugs.

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Inspect for bare or shorted ignition wires.

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Inspect for loose ignition coil grounds. Refer to Electronic Ignition (EI) System Diagnosis .

Here is the code list for the 1990 OBD1 system on your Acura.
Code 0 and 11 Electronic Control Module (ECM)
Code1 Heated oxygen sensor A
Code 2 Oxygen content B
Code 3 and 5 Manifold Absolute Pressure
Code 4 Crank position sensor
Code 6 Engine coolant temperature
Code 7 Throttle position sensor
Code 8 Top dead center sensor
Code 9 No.1 cylinder position sensor
Code 10 Intake air temperature sensor
Code 12 Exhaust recirculation system
Code 13 Barometric pressure sensor
Code 14 Idle air control valve or bad ECM
Code 15 Ignition output signal
Code 16 Fuel Injector
Code 17 Vehicle speed sensor
Code 19 A/T lock-up control solenoid
Code 20 Electric load detector
Code 21 V-TEC control solenoid
Code 22 V-TEC pressure solenoid
Code 23 Knock sensor
Code 30 A/T FI signal A
Code 30 A/T FI signal B
Code 41 Heated oxygen sensor heater
Code 43 Fuel supply system
Code 45 Fuel supply metering
Code 48 Heated oxygen sensor
Code 61 Front heated oxygen sensor
Code 63 Rear heated oxygen sensor
Code 65 Rear heated oxygen sensor heater
Code 67 Catalytic converter system
Code 70 Automatic transaxle
Code 71 Misfire detected cylinder 1
Code 72 Misfire detected cylinder 2
Code 73 Misfire detected cylinder 3
Code 74 Misfire detected cylinder 4
Code 75 Misfire detected cylinder 5
Code 76 Misfire detected cylinder 6
Code 80 Exhaust recirculation system
Code 86 Coolant temperature
Code 92 Evaporative emission control system

First you need to determine if it is spark or fuel.
Try some spray starting fluid or use in inductive timing light to see if there is spark at the plugs.
Then if the problem is fuel, you would need to put a pressure gauge on the line, check the O2, air mass, and temp sensors with an ohmmeter. (bad usually are 0 or infinite)
Could also be relay or control module.
If spark, it could be fuse, ignition switch, or crank position sensor/distributor pickup.

Next time have components tested before replacing them.

2 airflow sensor out of operating range 3 coolant temp sensor out of operating range 4 oxy sensor indicates full rich 5 throttle potentiometer/airflow sensor... (low throttle pot signal with high airflow sensor signal) 6 throttle pot/airflow sensor...... (high throttle pot signal with low airflow sensor signal) 7 throttle pot...idle fuel adjustment failure(idle speed??) 8 intake air temp sensor...open or shorted circuit to sensor 11 Throttle pot at idle: Throttle pot idle trim out of normal range 12 Airflow meter: MAF signal out of range 14 Coolant thermistor: Resistance out of range or static during engine warm up 16 Air thermistor: Resistance out of range 17 Throttle pot: Out of range 18 Throttle pot/Airflow: Low throttle pot signal at high airflow 19 Throttle pot/Airflow: High throttle pot signal at low airflow 22 Fuel pump drive: ECU output to fuel pump relay 23 Fuel supply: Engine running too rich 24 Ignition Drive: ECU output to ignition Amp 26 Air leak: Engine running too lean 29 ECU self check 33 Injector Drive: ECU output to injectors 34 Injector: Looks for Injector dribble 37 EGR Drive: ECU output to EGR switching valve 39 EGR check sensor: EGR not working (normally pipe blocked) 44 Lambda (O2) sensor: Poor mixture control rich or weak (or misfire) 46 Idle speed Control valve: ECU output to Coil AB 47 Idle speed Control valve: ECU output to Coil CD 48 Idle Speed Control Valve: Stepper motor grossly out of position 66 Air pump: ECU output to air pump relay 68 Road speed sensor: Seen speed < 5km/h at high engine airflow 69 Drive/Neutral switch: Seen cranking in "D" or high airflow in "N" 89 Purge Valve drive: ECU output to purge valve
this is all I could find

does it have a cold start injector seperate from the other injectors usually on the upper intake somewhere with a fuel line going to it

most likely idle air control sensor or low engine coolant I know sounds funny but IAC uses coolant to regulate idle. Idle air control valve or throttle body positioning sensor.

What all did the mechanic check ? Just codes . Did the mechanic check engine sensor data paramitors ? Checks
Action
DEFINITION: The engine runs unevenly during idle. If the condition is severe, the engine or the vehicle may shake. The engine idle speed may vary in RPM. Either condition can be severe enough to stall the engine.
Preliminary Check
Refer to Symptoms - Engine Controls .
Sensor Checks
• Check the heated oxygen sensor (HO2S).
Check for silicon contamination from fuel or from an improperly-used sealant. The sensor will have a white powdery coating. The sensor will produce a high but false signal voltage, or indicate a rich exhaust. The control module will reduce the amount of fuel delivered to the engine, causing a severe driveability problem.
• Check the throttle position (TP) sensor. If a sticking throttle shaft or binding linkage causes a high TP sensor open throttle indication, the control module will not control the idle. Monitor the TP sensor voltage. A scan tool or voltmeter should read less than 0.85 volts with the throttle closed.
• Check the engine coolant temperature (ECT) sensor using the scan tool in order to compare the engine coolant temperature with the ambient air temperature on a cold engine. If the coolant temperature reading is more than 5 degrees more than or less than the ambient air temperature on a cold engine, check for a high resistance in the coolant sensor circuit or the sensor itself.
• Check the manifold absolute pressure (MAP) sensor response and accuracy.
Fuel System Checks
• Check the fuel pressure. Refer to Fuel System Diagnosis .
• Check to determine if a rich or lean system causes the condition. Drive the vehicle at the speed of the complaint. Monitoring the fuel trim will help to identify the problem.
- Lean--The long term fuel trim is more than 150.
- Rich--The long term fuel trim is less than 115.
• Perform the fuel injector balance test. Refer to Fuel Injector Balance Test with Tech 2 .
• Check the fuel injector driver circuit.
1. Disconnect the injector harness connector at the injectors.
2. Connect an injector test lamp between the terminals of each injector connector and note the lamp while cranking.
3. If the test lamp fails to blink at any connector, the test lamp has a faulty injector drive circuit harness, connector, or terminal.
• Perform the fuel injector coil test. Refer to Fuel Injector Solenoid Coil Test .
• Check the evaporative emission (EVAP) control system.
Ignition System Checks
• Check the ignition output using the J 26792 Spark Tester or the equivalent. Refer to Distributor Ignition (DI) System Diagnosis .
• Check for the following conditions:
- Wet plugs
- Cracks
- Wear
- Improper gap
- Burned electrodes
- Blistered insulators
- Heavy deposits
• Check the spark plug wires by connecting a DMM to the ends of each wire in question. If the meter reads over 30,000 ohms, then replace the wires.
Additional Checks
• Check for vacuum leaks. Vacuum leaks can cause a higher than normal idle and low idle air control (IAC) counts.
• Check the IAC operation. Refer to Idle Air Control (IAC) System Diagnosis .
• Check the control module grounds for being clean, tight, and in their proper locations.
• Check the scan tool to determine if the control module is receiving an A/C signal. If a problem exists with the A/C ON, check the A/C system operation.
• Check for the exhaust gas recirculation (EGR) being ON while idling which will cause roughness, stalling, and hard starting.
• Check the battery cables and ground straps. The cables and straps should be clean and secure.
• Check the crankcase ventilation valve for proper operation by placing a finger over the inlet hole in the valve end several times. The valve should snap back. If the valve does not snap back, replace the valve.

Since this is an intermittent problem, first try to determine if the problem arises due to one of these many intermittent problems:

* Vehicle vibration
* Heat sensitive
* Freezing
* Water intrusion
* Electrical load
* Cold or hot start up

If you can't isolate the cause of the intermittent problem, you can try adjusting the Idle Speed/Ignition Timing/Idle Mixture Ratio:

Idle Speed/Ignition Timing/Idle Mixture Ratio Adjustment

PREPARATION
1) Make sure that the following parts are in good order.

* Battery
* Ignition system
* Engine oil and coolant levels
* Fuses
* ECM harness connector
* Vacuum hoses
* Air intake system
* (Oil filler cap, oil level gauge, etc.)
* Fuel pressure
* Engine compression
* EGR valve operation (If so equipped)
* Throttle valve
* Evaporative emission system

2) On air conditioner equipped models, checks should be carried out while the air conditioner is OFF.
3) On automatic transmission equipped models, when checking idle rpm, ignition timing and mixture ratio,
checks should be carried out while shift lever is in “N” position.
4) When measuring “CO” percentage, insert probe more than 40 cm (15.7 in) into tail pipe.
5) Turn off headlamps, heater blower, rear defogger.
6) Keep front wheels pointed straight ahead.
7) Make the check after the cooling fan has stopped.

INSPECTION PROCEDURE

1 INSPECTION START
1. Visually check the following:
I Air cleaner clogging
I Hoses and ducts for leaks
I EGR valve operation (If so equipped)
I Electrical connectors
I Gasket
I Throttle valve and throttle position sensor operation
2. Start engine and warm it up until engine coolant temperature indicator points to the middle of gauge.
Ensure engine stays below 1,000 rpm.
3. Open engine hood and run engine at about 2,000 rpm for about 2 minutes under no-load.
4. Perform diagnostic test mode II (Self-diagnostic results).
OK or NG
OK ' GO TO 2.
NG ' 1. Repair or replace components as necessary.
2. GO TO 2.

2 CHECK IGNITION TIMING
1. Run engine at about 2,000 rpm for about 2 minutes under no-load.
2. Rev engine (2,000 to 3,000 rpm) two or three times under no-load, then run engine at idle speed.
3. Turn off engine and disconnect throttle position sensor harness connector.
4. Start and rev engine (2,000 - 3,000 rpm) two or three times under no-load, then run at idle speed.
5. Check ignition timing with a timing light.
15°±2° BTDC (in “P” or “N” position)
OK or NG
OK ' GO TO 4.
NG ' GO TO 3.

3 ADJUST IGNITION TIMING
1. Adjust ignition timing by turning distributor after loosening securing bolts.
2. Turn off engine and connect throttle position sensor harness connector to throttle position sensor.
' GO TO 2.


4 CHECK BASE IDLE SPEED
1. Check idle speed.
700±50 rpm (in “P” or “N” position)
OK or NG
OK ' GO TO 6.
NG ' GO TO 5.

5 ADJUST BASE IDLE SPEED
1. Rev engine (2,000 to 3,000 rpm) 2 or 3 times under no-load then run engine at idle speed.
2. Adjust idle speed by turning idle speed adjusting screw.
700±50 rpm (in “P” or “N” position)
' GO TO 6.

6 CHECK TARGET IDLE SPEED
1. Turn off engine and connect throttle position sensor harness connector.
2. Start and rev engine (2,000 to 3,000 rpm) 2 or 3 times under no-load then run at idle speed.
3. Check idle speed.
750±50 rpm (in “P” or “N” position)
OK or NG
OK ' GO TO 9.
NG ' GO TO 7.

7 DETECT MALFUNCTIONING PART
Check the following.
1. Check IACV-AAC valve and replace if necessary.
2. Check IACV-AAC valve harness and repair if necessary.
3. Check ECM function by substituting another known good ECM.
(ECM may be the cause of a problem, but this is rarely the case.)
' GO TO 9.

9 CHECK FRONT HEATED OXYGEN SENSOR LH SIGNAL
1. Run engine at about 2,000 rpm for about 2 minutes under no-load.
2. Set “Left bank front heated oxygen sensor monitor” in the Diagnostic Test Mode II.
3. Make sure that MIL goes on more than 5 times during 10 seconds at 2,000 rpm.
OK or NG
OK ' GO TO 12.
NG (MIL does not blink.) ' GO TO 17.
NG (MIL blinks less than 5 times.)
' 1. Replace front heated oxygen sensor LH.
2. GO TO 10.


10 CHECK FRONT HEATED OXYGEN SENSOR LH SIGNAL
1. Warm engine to normal operating temperature.
2. Run engine at approx. 2000 rpm for approx. 2 minutes under no-load.
3. Set “Left bank front heated oxygen sensor monitor” in the Diagnostic Test Mode II.
4. Make sure that MIL goes on more than 5 times during 10 seconds at 2,000 rpm.
OK or NG
OK ' GO TO 13.
NG ' GO TO 11.

11 DETECT MALFUNCTIONING PART
Check the following.
1. Check fuel pressure regulator.
2. Check mass air flow sensor and its circuit.
3. Check injector and its circuit.
Clean or replace if necessary.
4. Check engine coolant temperature sensor and its circuit.
5. Check ECM function by substituting another known good ECM.
(ECM may be the cause of a problem, but this is rarely the case.)
' GO TO 2.


13 CHECK FRONT HEATED OXYGEN SENSOR RH SIGNAL
1. Set “Right bank front heated oxygen sensor monitor” in the Diagnostic Test Mode II.
2. Make sure that MIL goes on more than 5 times during 10 seconds at 2,000 rpm.
OK or NG
OK ' INSPECTION END
NG (MIL does not blink.) ' GO TO 16.
NG (MIL blinks less than 5 times.)
' 1. Replace front heated oxygen sensor RH.
2. GO TO 14.


14 CHECK FRONT HEATED OXYGEN SENSOR RH SIGNAL
1. Warm engine to normal operating temperature.
2. Run engine at approx. 2000 rpm for approx. 2 minutes under no-load.
3. Set “Right bank front heated oxygen sensor monitor” in the Diagnostic Test Mode II.
4. Make sure that MIL goes on more than 5 times during 10 seconds at 2,000 rpm.
OK or NG
OK ' INSPECTION END
NG ' GO TO 15.

15 DETECT MALFUNCTIONING PART
Check the following.
1. Check fuel pressure regulator.
2. Check mass air flow sensor and its circuit.
3. Check injector and its circuit. Clean or replace if necessary.
4. Check engine coolant temperature sensor and its circuit.
5. Check ECM function by substituting another known good ECM.
(ECM may be the cause of a problem, but this is rarely the case.)
' GO TO 2.
16 CHECK FRONT HEATED OXYGEN SENSOR RH HARNESS
1. Turn off engine and disconnect battery ground cable.
2. Disconnect ECM harness connector.
3. Disconnect front heated oxygen sensor RH harness connector.
4. Check harness continuity between ECM terminal 50 and front heated oxygen sensor RH harness connector.
Continuity should exist.
OK or NG
OK ' 1. Connect ECM harness connector.
2. GO TO 18.
NG ' 1. Repair or replace harness.
2. GO TO 9.

17 CHECK FRONT HEATED OXYGEN SENSOR LH HARNESS
1. Turn off engine and disconnect battery ground cable.
2. Disconnect ECM harness connector.
3. Disconnect front heated oxygen sensor LH harness connector.
4. Check harness continuity between ECM terminal 51 and front heated oxygen sensor LH harness connector.
Continuity should exist.
OK or NG
OK ' 1. Connect ECM harness connector.
2. GO TO 18.
NG ' 1. Repair or replace harness.
2. GO TO 9.

18 PREPARATION FOR “CO” % CHECK
1. Disconnect engine coolant temperature sensor harness connector.
2. Connect a resistor (4.4 kW) between terminals of engine coolant temperature sensor harness connector.
' GO TO 19.

19 CHECK “CO” %
1. Start engine and warm it up until engine coolant temperature indicator points to the middle of gauge.
2. Rev engine (2,000 to 3,000 rpm) two or three times under no-load, then run engine at idle speed.
3. Check “CO” %.
Idle CO: 1.5 - 9%
After checking CO%,
a. Disconnect the resistor from terminals of engine coolant temperature sensor.
b. Connect engine coolant temperature sensor harness connector to engine coolant temperature sensor.
OK or NG
OK ' 1. Replace front heated oxygen sensor LH.
2. GO TO 10.
NG ' GO TO 20.

20 DETECT MALFUNCTIONING PART
Check the following.
1. Connect front heated oxygen sensor harness connectors to front heated oxygen sensors.
2. Check fuel pressure regulator.
3. Check mass air flow sensor and its circuit.
4. Check injector and its circuit.
Clean or replace if necessary.
5. Check engine coolant temperature sensor and its circuit.
6. Check ECM function by substituting another known good ECM.
(ECM may be the cause of a problem, but this is rarely the case.)
' GO TO 2.