Question about 1992 Ford Bronco

1 Answer

92 bronco with ongoing rich fuel problem, and pcm issue

92 bronco 351w 5.8 new question regarding the computer. If the coolant sensor connectors are only reading 2.5 volts with the ignition on, could this be the the pcm failure that I suspect, or high restance in the wire loom? even after all the known bad sensors were replaced, and the codes cleared, the codes come back immediately, and there's 20 of them. thats why I suspect the ecm. any thoughts?

Posted by on

Ad

1 Answer

  • Level 2:

    An expert who has achieved level 2 by getting 100 points

    MVP:

    An expert that gotĀ 5 achievements.

    Governor:

    An expert whose answer gotĀ voted for 20 times.

    Hot-Shot:

    An expert who has answered 20 questions.

  • Expert
  • 56 Answers

It is the ECM

Posted on Jul 21, 2009

Ad

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
goodluck!

Posted on Jan 02, 2017

Ad

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

1995 dodge ram 1500 318 motor it wont get fire where is the logic module located


Under hood,passenger side mounted on the firewall,but ...
Could be something else ,crank sensor or cam,or ign.rotor ect.
The module like 3 hundred bucks.Try this ,turn the key
on-off-on-off-on( without out hitting the starter) the check
engine light should begin to flash.
Here is a code list,may narrow down the problem.
Diagnostic Trouble Code Descriptions and service hints. Fault Code DRB Display Code Description. Service hints. 11 No Crank reference signal at PCM No Distributor reference signal detected during engine cranking. Check the circuit between the distributor and PCM. 12 Battery Disconnect Direct Battery input to PCM disconnected within last 50 ignition key-on cycles. Normal if battery has been disconnected, otherwise check battery power and ground connections. 13** No change in MAP from start to run No difference seen between the engine MAP reading and the barometric (atmospheric) pressure reading at startup. Indicates a problem with the MAP sensor vacuum system. 14** MAP sensor voltage too low or too high MAP sensor voltage output is outside the acceptable range. 15** No Vehicle speed sensor signal No signal received from the vehicle speed sensor during road load operation. 17* Engine is cold too long Engine temperature too high or too low while traveling. Check coolant level, radiator cap, temperature sensor, and thermostat. 21** O2S Stays at center O2S shorted to voltage O2 sensor does not detect rich or lean condition, or O2 sensor input voltage too high. DRB will indicate which side with dual sensors. The O2 sensor signal should fluctuate under normal conditions. 22** ECT sensor voltage too high or too low Engine Coolant temperature sensor input out of normal range. Check engine temperature sensor. 23** Intake air temp sensor voltage too high or low Intake air manifold temperature sensor is out of range. Check sensor. 24** Throttle position sensor voltage too high or low TPS sensor is out of normal range. 25** Idle air control motor circuits A short is detected in one or more of the idle air motor circuits. 27* Injector # control circuit Injector number # output driver circuit does not respond to the control signal. Check the affected circuit. 31** EVAP Solenoid Circuit Short or open in the EVAP solenoid circuit. Check for loose, broken, or shorted wire in the charcoal canister purge solenoid wiring and connectors. 32** EGR Solenoid circuit Short or open in the EGR solenoid circuit. Check for loose, broken, or shorted wire in the EGR valve wiring and connectors. Possible air fuel ratio imbalance not detected during diagnosis. 33* AC clutch relay circuit Short or open in the AC clutch circuit. 34* Speed control circuit or speed control switch always low or high An open or short in the speed control vacuum or vent circuits. Speed control switch input above or below normal range. 35 Radiator Fan low speed relay circuit Open or short in the radiator fan relay wiring. 37** Torque converter clutch solenoid CKT or Trans temp sensor too high or low Open or short in CKT wiring or connectors. Voltage out of range at transmission temperature sensor input. See NOTE #1 below 41** Generator field not switching properly Open or short in the generator (alternator) field control (regulator) circuit. This indicates a problem with the charging circuit and the fault is set when the battery voltage from the ASD relay falls below 11.75 volts. Wiring, connectors, fuses, and the ASD relay should be checked. A shorted battery cell can also trigger this fault. 42* Auto shutdown relay circuit Open or short in the ASD relay wiring or connectors. 43** Ignition coil circuit # Open or short in number # coil circuit. Indicates that the ignition coil's peak primary circuit current is not achieved with the maximum dwell time. 44* Battery temp sensor volts out of range An open or short in the engine coolant temperature sensor circuit or a problem in the PCM's battery temperature circuit. 45* Trans OD solenoid circuit Transmission OD solenoid circuit failure. Open or short in the transmission overdrive solenoid circuit. 46** Charging system voltage too high Battery voltage sense input above target charging voltage during engine operation. Computer is indicating that the battery voltage is not being regulated. 47** Charging system voltage too low Battery voltage sense input above target charging voltage during engine operation. Also, no significant change in battery voltage was detected during a test of the generator output. 51** System lean L-Idle Adap at rich limit or lean R-Idle Adap at rich limit O2 sensor signal indicates lean air/fuel ratio during engine operation. The computer ran the mixture to the rich limit of programming, but the O2 sensor still indicated a lean condition. L or R indicate left or right side O2 sensor. Fuel pressure problems can lean the mixture and set this fault. 52** System rich L-Idle Adap at lean limit or rich R-Idle Adap at lean limit O2 sensor signal indicates rich air/fuel ratio during engine operation. The computer ran the mixture to the lean limit of programming, but the O2 sensor still indicated a rich condition. L or R indicate left or right side O2 sensor. Faulty ignition components, high or low fuel pressure, or leaking injectors can set this fault. 53* Internal PCM failure or PCM SPI comm failure An internal PCM failure or PCM communications failure has been detected. 54* No cam sync signal at PCM No fuel sync (camshaft signal) detected during engine crank. No camshaft position sensor signal was received from the distributor. Problem with the distributor synchronization circuit. 55 N/A End of message code. A DTC 55 is used to end all DTC messages. This code does not show on the DRB tool and indicates a completion of the stored codes on the Malfunction Indicator Lamp (check engine lamp). 62* PCM failure SRI miles not stored Unsuccessful attempt to update Service Reminder Indicator miles in the PCM EEPROM (memory). 63* PCM Failure EEPROM write denied Unsuccessful attempt to write and EEPROM location by the PCM. Controller failure, check the PCM. This code can be set when attempting an unauthorized reprogram of the PCM. 71** Aux 5V signal voltage low The auxiliary 5 volt supply output voltage is low. The 5 volt output signal is not reaching the required voltage level. 72** Catalytic Converter efficiency failure The catalytic converter is not converting emissions in the proper ratio.

Feb 22, 2013 | Cars & Trucks

1 Answer

Why is my 89 ford bronco running so rich


I saw what you replaced, didn't see any testing? Any applicable trouble codes?
Did you use a gage and check proper fuel pressure? My info on that engine size, said 35--45 psi. If the fuel pressure is too high, check the return line. As far as the fuel pressure regulator, do you have vacuum?

Jun 17, 2017 | 1989 Ford Bronco

1 Answer

2000 Ford Explorer, trouble code #PO171


PO121 : TP Sensor Performance = The PCM supplies 5V to the TP sensor(throttle position). The TP sensor is a variable resistor that drops the voltage to about 4 volts at WOT(wide open throttle) to less than 1 volt at closed throttle. Some TP sensors are adjustable. others have a learn procedure to determine closed throttle. PO171 Fuel Trim System Lean = In closed loop the PCM adjusts fuel delivery based on H2OS 1 readings and is indicated by long & short fuel trim values. If lean the PCM will add fuel (fuel trim above 0%) & if rich the PCM will reduce fuel(fuel trim below 0%) PO128 ECT Below Thermostat Regulating Temperature = possible failed thermostat, low or empty on coolant, Engine Coolant Temp Sensor, Poor connection/Harness/Wires, faulty PCM Connection. I think you hit the nail on the head , the ECT Sensor ( which is different than the temp sensor for the dash gauge)

Jun 04, 2011 | 2000 Ford Explorer

1 Answer

PO121 code still on, replaced o2 sensors, replaced cracked air tube, put seafoam in gas. reset computer, light came back on after 40 miles. same codes. DIAGNOSTIC TROUBLE CODES PO171 System Too Lean...


PO121 : TP Sensor Performance = The PCM supplies 5V to the TP sensor(throttle position). The TP sensor is a variable resistor that drops the voltage to about 4 volts at WOT(wide open throttle) to less than 1 volt at closed throttle. Some TP sensors are adjustable. others have a learn procedure to determine closed throttle. PO171 Fuel Trim System Lean = In closed loop the PCM adjusts fuel delivery based on H2OS 1 readings and is indicated by long & short fuel trim values. If lean the PCM will add fuel (fuel trim above 0%) & if rich the PCM will reduce fuel(fuel trim below 0%) PO128 ECT Below Thermostat Regulating Temperature = possible failed thermostat, low or empty on coolant, Engine Coolant Temp Sensor, Poor connection/Harness/Wires, faulty PCM Connection. I think you hit the nail on the head , the ECT Sensor ( which is different than the temp sensor for the dash gauge)

Jan 18, 2011 | 1999 Kia Sephia

1 Answer

97 grand am code P0118


Engine Coolant Temperature Circuit High Input
What does that mean?

The engine coolant temperature (ECT) sensor is a thermistor screwed into a coolant passage in the cylinder head. Sensor resistance is high when coolant temperature is low and resistance drops when coolant temperature increases. The powertrain control module (PCM) provides a 5 volt reference and a ground to the sensor. The PCM monitors voltage drop to determine coolant temperature. If the ECT reads less than freezing temp. when engine has been running for more than a few minutes, the PCM determines a circuit fault and sets this code. Or if the PCM determines the sensor resistance is out of specs, this code is set.
FB.init("dd7d9e9681341cde77587bc6a2029f6f"); OBD-Codes.com on Facebook Potential Symptoms

Symptoms of a P0118 could include:

  • Very poor fuel economy
  • A no start condition
  • Vehicle may start, but run very poorly, blowing black smoke, running very rough and misfiring
  • Illumination of MIL
Causes

A code P0118 may mean that one or more of the following has happened:

  • A bad connection at the sensor
  • An open in the ground circuit between the ECT sensor and the PCM
  • A short in the voltage feed between the sensor and the PCM
  • A bad PCM (less likely)
  • A bad temperature sensor (shorted internally)
Possible Solutions

First, if you have access to a scan tool, check the reading of the coolant sensor. Does it read a logical number? If so, the problem is likely intermittent. Perform a "wiggle" test by wiggling the connector and harness to the sensor while watching the reading on the scan tool. Watch for any drop-outs. Drop-outs would indicate a bad connection. If the scan tool reads an illogical temperature, check the resistance of the temperature sensor. If it is out of specs, replace it. If it is in specifications, unplug the sensor and, using a fused jumper wire, jumper the two terminals of the connector together. The temperature reading should now be maxed out to above 250 degrees F. If not, there is likely a problem with the ground circuit or voltage supply.

Check for 5 volts reference voltage at the connector. Also check for ground presence at the connector. If you do not have 5V ref. and/or ground continuity, check for these back at the PCM connector. If you have these at the PCM connector, then repair open or short between the PCM and the sensor. If you do not, remove the offending wire from the PCM and then check for proper voltage at the PCM pin. If it's present now, repair short on the circuit. If it isn't present after removing the wire and checking the pin, replace PCM

NOTE: Usually, P0118 is indicative of a bad temperature sensor, but doesn't rule out these other possibilities. If you're unsure of how to diagnose a PCM, do not attempt. The sensor is located near the thermostat housing on the top of the engine

Nov 04, 2010 | Pontiac Grand Am Cars & Trucks

1 Answer

1998 Honda accord code PO118


P0118 - Engine Coolant Temperature Circuit High Input

What does that mean?
The engine coolant temperature (ECT) sensor is a thermistor screwed into a coolant passage in the cylinder head. Sensor resistance is high when coolant temperature is low and resistance drops when coolant temperature increases. The powertrain control module (PCM) provides a 5 volt reference and a ground to the sensor. The PCM monitors voltage drop to determine coolant temperature. If the ECT reads less than freezing temp. when engine has been running for more than a few minutes, the PCM determines a circuit fault and sets this code. Or if the PCM determines the sensor resistance is out of specs, this code is set.

Symptoms of a P0118 could include:
* Very poor fuel economy
* A no start condition
* Vehicle may start, but run very poorly, blowing black smoke, running very rough and misfiring
* Illumination of MIL

Causes
A code P0118 may mean that one or more of the following has happened:
* A bad connection at the sensor
* An open in the ground circuit between the ECT sensor and the PCM
* A short in the voltage feed between the sensor and the PCM
* A bad PCM (less likely)
* A bad temperature sensor (shorted internally)

Possible Solutions
First, if you have access to a scan tool, check the reading of the coolant sensor. Does it read a logical number? If so, the problem is likely intermittent. Perform a "wiggle" test by wiggling the connector and harness to the sensor while watching the reading on the scan tool. Watch for any drop-outs. Drop-outs would indicate a bad connection. If the scan tool reads an illogical temperature, check the resistance of the temperature sensor. If it is out of specs, replace it. If it is in specifications, unplug the sensor and, using a fused jumper wire, jumper the two terminals of the connector together. The temperature reading should now be maxed out to above 250 degrees F. If not, there is likely a problem with the ground circuit or voltage supply.

Check for 5 volts reference voltage at the connector. Also check for ground presence at the connector. If you do not have 5V ref. and/or ground continuity, check for these back at the PCM connector. If you have these at the PCM connector, then repair open or short between the PCM and the sensor. If you do not, remove the offending wire from the PCM and then check for proper voltage at the PCM pin. If it's present now, repair short on the circuit. If it isn't present after removing the wire and checking the pin, replace PCM

NOTE: Usually, P0118 is indicative of a bad temperature sensor, but doesn't rule out these other possibilities. If you're unsure of how to diagnose a PCM, do not attempt.

Other engine coolant engine light codes: P0115, P0116, P0117, P0118, P0119, P0125, P0128

Hope helps.

Jun 06, 2010 | 1998 Honda Accord

1 Answer

92 FULL SIZE BRONCO NOT GETTING FUEL. RUNS ON STARTING FLUID. NOT SURE IF IT IS ELECTRICAL OR PUMP. DON'T HAVE MANUAL,DON'T KNOW WHERE FUSE OR CUBE IS. I DO NOT HERE NOISE IN TANK WHEN KEY IS FORWARD. IS...


hotwire the circuit by grounding the FP lead of the DLC connector (located on the back fender apron drivers side) with the ignition switch on. As the fuel pump is normally under control of the PCM, this will mimic a power on signal from the PCM, and you can hear the pump come on.

Mar 21, 2010 | 1992 Ford Bronco

1 Answer

I have a 1994 ford bronco with a 5.8 351w. when ignition is turned to accessories the fuel pump will come on for 2-3 sweconds then go off,but after a few minutes it will come on and stay on. when the...


Take your Bronco to an Autozone or Oreillys for a free scan. Offhand a new ignition switch would seem like a good idea, because the fuelpump should not be working in the ACC position.
If a new ignition switch does not help the fuelpump problem the pump is wired to an accessory. You need to look up the fuse info in an owners manual.

Dec 01, 2009 | 1989 Ford F 150

1 Answer

Ongoing problem. On the 92 bronco with the 351w, replaced o2 sensor, idle air bypass, which was sticking, put in a msd coil, cap,wires. cleaned all the plugs again, and let the cylynders air out. replaced...


ignition module in the distributor may be breaking down!
its a common fault as they dont like getting hot!
spark plug gap is critical with these types of sytems
test each plug as you may have fractured one when fitting it

Jul 19, 2009 | 1992 Ford Bronco

2 Answers

Weak spark from dist cap to plugs. spark from coil primary is as it should be. Plugs were carbon fouled from rich condition. this is a 92 bronco 5.8 windsor motor.changed out plugs,cap,rotor,and remote tfi...


The engine is definitely in an over rich fuel condition if you are blowing black smoke. I would suspect a bad 02 sensor, but the flooding condition you describe at starting could be other things. I would check the codes and proceed from there.

Jul 13, 2009 | 1992 Ford Bronco

Not finding what you are looking for?
1992 Ford Bronco Logo

Related Topics:

207 people viewed this question

Ask a Question

Usually answered in minutes!

Top Ford Experts

yadayada
yadayada

Level 3 Expert

76164 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22156 Answers

fordexpert

Level 3 Expert

5522 Answers

Are you a Ford Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...