Newbie here! 90 Max won't start!!!! Help! Anyone!
longislandmax
12-20-2004, 09:25 AM
1990 Maxima ; I just replced the fuel pump and i hear it workin but i can't get it to turn over. Where do i start to find the problem??one thing i noticed that the security light is blinking, would that prevent it from starting { it is cranking}. I am trying to fix it for a friend. any suggestions would be great!!
Nahkapohjola
12-20-2004, 10:05 AM
1990 Maxima ; I just replced the fuel pump and i hear it workin but i can't get it to turn over. Where do i start to find the problem??one thing i noticed that the security light is blinking, would that prevent it from starting { it is cranking}. I am trying to fix it for a friend. any suggestions would be great!!
Engine needs gas, air, spark with proper timing to work. Which is missing?
Testing:
- ECU error codes can be read dirsctly from ECU, read.
- Is gas pressure up at the injectors? Loosen a clamp to get your finger wet...
- Do injectors click?
- Install one spare spark plug to see spark on the grounded gap.
-----------------------------------------------------------------------
10.11 Nissan Electronics Diagnosis
Section Index
Main Index
http://www.parttrackers.com/library/1/93/104/
*ECCS and self-criticism
For years, Nissan called its computerized engine management set-up "ECCS," which stands for "Electronic Concentrated Control System." One interesting aspect of this system is its three strategies for handling malfunctions. If the computer receives a coolant temperature or detonation sensor signal that's out of range, the "Fail-Safe" mode is engaged. Stored data is substituted for the faulty signal, which is ignored. In the "Backup" mode, information from a bad sensor circuit's replaced by that from a good one. For instance, if the air flow meter is in trouble, the PCM relies on the throttle position sensor signal instead. Finally, if the brain itself has some kind of electronic hemorrhage, there's the "Limp-Home" mode wherein the car remains "minimally driveable," as the factory training literature so honestly states.
Nissan's made a commendable effort to help us by incorporating comprehensive self-diagnostics into its ECCS. While not exactly the be all and end all of troubleshooting, they can be a big help in getting you started on the right track by indicating the specific component or circuit that's the most likely cause of a driveability or performance problem.
Originally, Nissans carried two-mode self-diagnostics, but by '87 all models were endowed with a five-mode system. That's what we'll explore here, specifically the '91 federal version found on the popular Maxima.
When you get a driveability complaint and/or the Check Engine light is on (Nissans didn't get this warning device until '88 for California and '89 federally), you'll naturally check all the basics first, right? The next logical step is to engage the self-diagnostics. Unlike most other carmakers, Nissan has you go right to the PCM for this. Remove it from the passenger's side kick panel, then find the mode selector screw and the port in the housing through which a red and a green LED are visible.
Switch on the ignition, turn the selector screw clockwise all the way, and watch the LEDs. They'll flash once, then pause, twice then pause, and on up to five times to indicate the five diagnostic modes. When you see the number of the mode you want, turn the screw counter-clockwise.
*Modes and codes
Mode 1 is called the "Exhaust Gas Sensor Monitor" because it informs you about oxygen sensor activity. With the engine running and fully warmed up, the green LED should blink, going on when the sensor sends a lean signal and off when it sends a rich signal. You should see 5-10 flashes every 10 seconds. If the LED is on more than it's off, there's a lean condition, and vice versa. Sluggish blinking should make you suspect a fouled sensor.
Mode 2, the Mixture Ratio Feedback Control Monitor, lets you know whether or not the air/fuel mixture is being controlled within the proper range. If the red and green LEDs flash pretty much simultaneously with the engine running, mix control is okay. If the red LED is off more often than the green one, richness is indicated. If the red is on more than its mate, think lean.
Mode 3 has the name "Self-Diagnostic," and it's more what you're used to on other vehicles because it yields fault codes, both hard and intermittent, which are communicated to you by means of the flashing of both LEDs. The red one gives the first digit, and the green one the second digit. For instance, if the red flashes twice, then the green flashes once, you've got a Code 21.
Get the engine up to normal temp, preferably by driving the car for 10 minutes, then pull the codes. In the case of a no-start, crank the engine for at least two seconds. If you see 55, all is well (in older models, 44 meant the same thing). Be sure to write down any other codes because they'll be erased when you go on to Mode 4, which means you will have lost any help on intermittents. Normally, codes are retained in memory for fifty starts.
Mode 4, called the "Switches On/Off Diagnostic Mode," checks the function of the switches that serve as inputs to the PCM, specifically those for ignition key start position, idle, and vehicle speed. For the first two, the red LED will go on or off when switch status is changed. In other words, with the ignition on, the red light should illuminate both when you step on the gas pedal and when you turn the key to start. If not, check the appropriate circuit. The vehicle speed sensor lights the green LED when you exceed 12 mph (get the drive wheels off the floor to do this in the shop, or have a helper drive while you keep your eyes on the PCM).
Mode 5 ("Real-Time") gives instantaneous trouble codes to let you know what's going on right now in four monitored circuits. Codes are flashed out just once when a malfunction is detected, then they're immediately forgotten. And the way you read them is different -- you observe the flashing of one LED or the other, the red one reporting on the crank angle sensor and the fuel pump circuits, and the green on the air flow meter and ignition signal circuits.
If the red LED pulses out a series of long flashes separated by equally long pauses, a malfunction in the crank angle sensor or its circuit's indicated. Groups of three short flashes of the red LED point to the fuel pump or its circuit. With the green LED, two medium flashes followed by a pause, then two again, and so on, should cause you to suspect the air flow meter and its related wiring. Groups of four flashes mean there's a problem with the ignition signal.
This is an extremely sensitive and very useful mode. You can wiggle wires and connectors, rap on components, and have somebody else drive the car while you watch for those fleeting indications of trouble. You'll know everything's okay if you see no flashing in five minutes of revving and idling.
A diligent search through many, many TSBs, perusals of factory literature, and conversations with specialists rendered the following items of special interest:
Nissan has made NAO (Non-Asbestos Organic) pads available to fix intractable squeal problems.
Fast-fill master cylinders should be manually bled, and instead of waiting the usual five seconds between having your helper let off the pedal and cracking the bleeder for the next stroke, it's necessary to give it at least 20 seconds.
When doing diagnosis that involves a green or blue relay for the fuel pump and A/C, be certain you know what you're probing -- hit the wrong terminal and you could fry the PCM.
A Code 45 (injector leak) may be caused by any sensor or circuit that can produce a rich signal, or by excessive fuel pressure.
Whenever you encounter a computer-shifted automatic that starts off in the wrong gear, the two most likely external causes are a loss of power or ground to the control system, or an initiation of the fail-safe mode.
Watch out for the titanium oxygen sensor that started showing up in '86. Instead of generating voltage, its resistance changes dramatically when the oxygen content of the exhaust reflects stoichiometry, so it's used to modify a one-volt reference signal from the computer in much the same way as a coolant temperature sensor. What happens is oxygen blocks the passage of electrons through the TiO2 element, and resistance rises sharply as the mix goes lean.
It's much less susceptible to lead poisoning than zirconium, but that's not a big consideration anymore. On the other hand, it's less tolerant of anti-freeze, and it needs to be kept at a very stable temperature in order to produce an accurate signal, so all specimens are electrically heated.
How can you tell whether or not the sensor you're looking at is titanium? In the case of Nissan, it'll have 12mm threads instead of the standard 18mm. And sometimes its wire will be color-coded red. In every instance, there's no atmospheric vent.
Idle speed fluctuation, a hard accel pedal, or jumpy acceleration on a 300ZX points to throttle chamber deposits. Dissolve them in the usual way, then caution the car's owner against overfilling the crankcase.
Again on the 300ZX, vibes at 10-20 mph are probably due to a deteriorated prop shaft center bearing.
If you ever have occasion to replace the turbocharger on a 300ZX for noise, make sure you get a "countermeasure" oil feed tube (part #15192-40P02).
"Stanzas have had lots of problems with engine mounts," Lightsey tells us. "You can practically revive the whole car just by replacing them. The deterioration is so gradual, people don't notice, but the car feels like an old rattle trap."
If you get a Nissan with an automatic that just won't move, don't start pulling the trans until you check the soft gear on the governor shaft -- Lightsey says they tend to strip out or the pin shears, and without governor pressure you're not going anywhere. Fixing it's an easy, external job.
Replacing that timing belt? Then make sure the new one is of the right tooth shape because both trapezoidal and curvalinear types have been used on the same engine.
----------------------------------------------------------------------
11 Crank Angle Sensor/Camshaft Position Sensor.
12 Air Flow Meter/Mass Air Flow Sensor.
13 Engine Coolant Temperature Sensor.
14 Vehicle Speed Sensor.
21 Ignition Signal.
22 Fuel Pump.
23 Idle Switch.
24 Throttle Valve Switch.
25 Idle Speed Control Valve.
28 Cooling Fan Circuit.
31 ECM.
32 EGR Function.
33 Heated Oxygen Sensor.
34 Knock Sensor.
35 Exhaust Gas Temperature Sensor.
36 EGR Control-Back Pressure Transducer.
37 Knock Sensor.
38 Right hand bank Closed Loop (B2).
41 Intake Air Temperature Sensor.
42 Fuel Temperature Sensor.
43 Throttle Position Sensor.
45 Injector Leak.
47 Crankshaft Position Sensor.
51 Injector Circuit.
53 Oxygen Sensor.
54 A/T Control.
55 No Malfunction.
63 No. 6 Cylinder Misfire.
64 No. 5 Cylinder Misfire.
65 No. 4 Cylinder Misfire.
66 No. 3 Cylinder Misfire.
67 No. 2 Cylinder Misfire.
68 No. 1 Cylinder Misfire.
71 Random Misfire.
72 TWC Function right hand bank.
73 TWC Function right hand bank.
76 Fuel Injection System Function right hand bank.
77 Rear Heated Oxygen Sensor Circuit.
82 Crankshaft Position Sensor.
84 A/T Diagnosis Communication Line.
85 VTC Solenoid Valve Circuit.
86 Fuel Injection System Function right hand bank.
87 Canister Control Solenoid Valve Circuit.
91 Front Heated Oxygen Sensor Heater Circuit right hand bank.
94 TCC Solenoid Valve.
95 Crankshaft Position Sensor.
98 Engine Coolant Temperature Sensor.
101 Front Heated Oxygen Sensor Heater Circuit right hand bank.
103 Park/Neutral Position Switch Circuit.
105 EGR and EGR Canister Control Solenoid Valve Circuit.
108 Canister Purge Control Valve Circuit.
Engine needs gas, air, spark with proper timing to work. Which is missing?
Testing:
- ECU error codes can be read dirsctly from ECU, read.
- Is gas pressure up at the injectors? Loosen a clamp to get your finger wet...
- Do injectors click?
- Install one spare spark plug to see spark on the grounded gap.
-----------------------------------------------------------------------
10.11 Nissan Electronics Diagnosis
Section Index
Main Index
http://www.parttrackers.com/library/1/93/104/
*ECCS and self-criticism
For years, Nissan called its computerized engine management set-up "ECCS," which stands for "Electronic Concentrated Control System." One interesting aspect of this system is its three strategies for handling malfunctions. If the computer receives a coolant temperature or detonation sensor signal that's out of range, the "Fail-Safe" mode is engaged. Stored data is substituted for the faulty signal, which is ignored. In the "Backup" mode, information from a bad sensor circuit's replaced by that from a good one. For instance, if the air flow meter is in trouble, the PCM relies on the throttle position sensor signal instead. Finally, if the brain itself has some kind of electronic hemorrhage, there's the "Limp-Home" mode wherein the car remains "minimally driveable," as the factory training literature so honestly states.
Nissan's made a commendable effort to help us by incorporating comprehensive self-diagnostics into its ECCS. While not exactly the be all and end all of troubleshooting, they can be a big help in getting you started on the right track by indicating the specific component or circuit that's the most likely cause of a driveability or performance problem.
Originally, Nissans carried two-mode self-diagnostics, but by '87 all models were endowed with a five-mode system. That's what we'll explore here, specifically the '91 federal version found on the popular Maxima.
When you get a driveability complaint and/or the Check Engine light is on (Nissans didn't get this warning device until '88 for California and '89 federally), you'll naturally check all the basics first, right? The next logical step is to engage the self-diagnostics. Unlike most other carmakers, Nissan has you go right to the PCM for this. Remove it from the passenger's side kick panel, then find the mode selector screw and the port in the housing through which a red and a green LED are visible.
Switch on the ignition, turn the selector screw clockwise all the way, and watch the LEDs. They'll flash once, then pause, twice then pause, and on up to five times to indicate the five diagnostic modes. When you see the number of the mode you want, turn the screw counter-clockwise.
*Modes and codes
Mode 1 is called the "Exhaust Gas Sensor Monitor" because it informs you about oxygen sensor activity. With the engine running and fully warmed up, the green LED should blink, going on when the sensor sends a lean signal and off when it sends a rich signal. You should see 5-10 flashes every 10 seconds. If the LED is on more than it's off, there's a lean condition, and vice versa. Sluggish blinking should make you suspect a fouled sensor.
Mode 2, the Mixture Ratio Feedback Control Monitor, lets you know whether or not the air/fuel mixture is being controlled within the proper range. If the red and green LEDs flash pretty much simultaneously with the engine running, mix control is okay. If the red LED is off more often than the green one, richness is indicated. If the red is on more than its mate, think lean.
Mode 3 has the name "Self-Diagnostic," and it's more what you're used to on other vehicles because it yields fault codes, both hard and intermittent, which are communicated to you by means of the flashing of both LEDs. The red one gives the first digit, and the green one the second digit. For instance, if the red flashes twice, then the green flashes once, you've got a Code 21.
Get the engine up to normal temp, preferably by driving the car for 10 minutes, then pull the codes. In the case of a no-start, crank the engine for at least two seconds. If you see 55, all is well (in older models, 44 meant the same thing). Be sure to write down any other codes because they'll be erased when you go on to Mode 4, which means you will have lost any help on intermittents. Normally, codes are retained in memory for fifty starts.
Mode 4, called the "Switches On/Off Diagnostic Mode," checks the function of the switches that serve as inputs to the PCM, specifically those for ignition key start position, idle, and vehicle speed. For the first two, the red LED will go on or off when switch status is changed. In other words, with the ignition on, the red light should illuminate both when you step on the gas pedal and when you turn the key to start. If not, check the appropriate circuit. The vehicle speed sensor lights the green LED when you exceed 12 mph (get the drive wheels off the floor to do this in the shop, or have a helper drive while you keep your eyes on the PCM).
Mode 5 ("Real-Time") gives instantaneous trouble codes to let you know what's going on right now in four monitored circuits. Codes are flashed out just once when a malfunction is detected, then they're immediately forgotten. And the way you read them is different -- you observe the flashing of one LED or the other, the red one reporting on the crank angle sensor and the fuel pump circuits, and the green on the air flow meter and ignition signal circuits.
If the red LED pulses out a series of long flashes separated by equally long pauses, a malfunction in the crank angle sensor or its circuit's indicated. Groups of three short flashes of the red LED point to the fuel pump or its circuit. With the green LED, two medium flashes followed by a pause, then two again, and so on, should cause you to suspect the air flow meter and its related wiring. Groups of four flashes mean there's a problem with the ignition signal.
This is an extremely sensitive and very useful mode. You can wiggle wires and connectors, rap on components, and have somebody else drive the car while you watch for those fleeting indications of trouble. You'll know everything's okay if you see no flashing in five minutes of revving and idling.
A diligent search through many, many TSBs, perusals of factory literature, and conversations with specialists rendered the following items of special interest:
Nissan has made NAO (Non-Asbestos Organic) pads available to fix intractable squeal problems.
Fast-fill master cylinders should be manually bled, and instead of waiting the usual five seconds between having your helper let off the pedal and cracking the bleeder for the next stroke, it's necessary to give it at least 20 seconds.
When doing diagnosis that involves a green or blue relay for the fuel pump and A/C, be certain you know what you're probing -- hit the wrong terminal and you could fry the PCM.
A Code 45 (injector leak) may be caused by any sensor or circuit that can produce a rich signal, or by excessive fuel pressure.
Whenever you encounter a computer-shifted automatic that starts off in the wrong gear, the two most likely external causes are a loss of power or ground to the control system, or an initiation of the fail-safe mode.
Watch out for the titanium oxygen sensor that started showing up in '86. Instead of generating voltage, its resistance changes dramatically when the oxygen content of the exhaust reflects stoichiometry, so it's used to modify a one-volt reference signal from the computer in much the same way as a coolant temperature sensor. What happens is oxygen blocks the passage of electrons through the TiO2 element, and resistance rises sharply as the mix goes lean.
It's much less susceptible to lead poisoning than zirconium, but that's not a big consideration anymore. On the other hand, it's less tolerant of anti-freeze, and it needs to be kept at a very stable temperature in order to produce an accurate signal, so all specimens are electrically heated.
How can you tell whether or not the sensor you're looking at is titanium? In the case of Nissan, it'll have 12mm threads instead of the standard 18mm. And sometimes its wire will be color-coded red. In every instance, there's no atmospheric vent.
Idle speed fluctuation, a hard accel pedal, or jumpy acceleration on a 300ZX points to throttle chamber deposits. Dissolve them in the usual way, then caution the car's owner against overfilling the crankcase.
Again on the 300ZX, vibes at 10-20 mph are probably due to a deteriorated prop shaft center bearing.
If you ever have occasion to replace the turbocharger on a 300ZX for noise, make sure you get a "countermeasure" oil feed tube (part #15192-40P02).
"Stanzas have had lots of problems with engine mounts," Lightsey tells us. "You can practically revive the whole car just by replacing them. The deterioration is so gradual, people don't notice, but the car feels like an old rattle trap."
If you get a Nissan with an automatic that just won't move, don't start pulling the trans until you check the soft gear on the governor shaft -- Lightsey says they tend to strip out or the pin shears, and without governor pressure you're not going anywhere. Fixing it's an easy, external job.
Replacing that timing belt? Then make sure the new one is of the right tooth shape because both trapezoidal and curvalinear types have been used on the same engine.
----------------------------------------------------------------------
11 Crank Angle Sensor/Camshaft Position Sensor.
12 Air Flow Meter/Mass Air Flow Sensor.
13 Engine Coolant Temperature Sensor.
14 Vehicle Speed Sensor.
21 Ignition Signal.
22 Fuel Pump.
23 Idle Switch.
24 Throttle Valve Switch.
25 Idle Speed Control Valve.
28 Cooling Fan Circuit.
31 ECM.
32 EGR Function.
33 Heated Oxygen Sensor.
34 Knock Sensor.
35 Exhaust Gas Temperature Sensor.
36 EGR Control-Back Pressure Transducer.
37 Knock Sensor.
38 Right hand bank Closed Loop (B2).
41 Intake Air Temperature Sensor.
42 Fuel Temperature Sensor.
43 Throttle Position Sensor.
45 Injector Leak.
47 Crankshaft Position Sensor.
51 Injector Circuit.
53 Oxygen Sensor.
54 A/T Control.
55 No Malfunction.
63 No. 6 Cylinder Misfire.
64 No. 5 Cylinder Misfire.
65 No. 4 Cylinder Misfire.
66 No. 3 Cylinder Misfire.
67 No. 2 Cylinder Misfire.
68 No. 1 Cylinder Misfire.
71 Random Misfire.
72 TWC Function right hand bank.
73 TWC Function right hand bank.
76 Fuel Injection System Function right hand bank.
77 Rear Heated Oxygen Sensor Circuit.
82 Crankshaft Position Sensor.
84 A/T Diagnosis Communication Line.
85 VTC Solenoid Valve Circuit.
86 Fuel Injection System Function right hand bank.
87 Canister Control Solenoid Valve Circuit.
91 Front Heated Oxygen Sensor Heater Circuit right hand bank.
94 TCC Solenoid Valve.
95 Crankshaft Position Sensor.
98 Engine Coolant Temperature Sensor.
101 Front Heated Oxygen Sensor Heater Circuit right hand bank.
103 Park/Neutral Position Switch Circuit.
105 EGR and EGR Canister Control Solenoid Valve Circuit.
108 Canister Purge Control Valve Circuit.
longislandmax
01-05-2005, 08:10 AM
Well i am getting spark, and i am getting fuel to the injectors, I checked the codes and getting a code 51 injector circut which can be caused when i changed out my fuel pump no? , and 34 knock sensor.I played around with the distributor and still nothing.I did notice some sort of ground wire from the inside fender and it was just sitting on the tranny housing, Don't know where it goes to.I can hear she wants to start up, shes right there. I really don't want to spray any starter fluid in the air intake, but i may have to. any ideas?
Nahkapohjola
01-05-2005, 08:19 AM
Well i am getting spark, and i am getting fuel to the injectors, I checked the codes and getting a code 51 injector circut which can be caused when i changed out my fuel pump no? , and 34 knock sensor.I played around with the distributor and still nothing.I did notice some sort of ground wire from the inside fender and it was just sitting on the tranny housing, Don't know where it goes to.I can hear she wants to start up, shes right there. I really don't want to spray any starter fluid in the air intake, but i may have to. any ideas?
There is not really very many things whcih can cause this if u along good spark also hear the injectors click (=ECU ok and giving pulses and injectors have coils ok.) Possible Bad knock sensor does only retartd ignition on higher rev, does not affect starting.
- fuel pressure: pump, regulator fails
- timing pulse from distributor (older models ECU will not allow start, newer type allows start in ECU safe mode(2000rpm limit)
That distr can be self measured, see my home site for sensor testing, test all.
There are lot of tips to work on on gnd & connectors. There's also link for online chilton manual, maybe it has a troubleshooting chart.
There is not really very many things whcih can cause this if u along good spark also hear the injectors click (=ECU ok and giving pulses and injectors have coils ok.) Possible Bad knock sensor does only retartd ignition on higher rev, does not affect starting.
- fuel pressure: pump, regulator fails
- timing pulse from distributor (older models ECU will not allow start, newer type allows start in ECU safe mode(2000rpm limit)
That distr can be self measured, see my home site for sensor testing, test all.
There are lot of tips to work on on gnd & connectors. There's also link for online chilton manual, maybe it has a troubleshooting chart.
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