Finally read codes

[firelt90bronco]

I just finished reading the codes for my 1990 Bronco. Can anyone tell me what they are and what would cause all these? They read as follows:

KOEO

31

KOER

21

31

41

52

25

 

[bobstrat]

2 Digit Codes

11

System OK

12

Idle Speed Control motor or Air Bypass not controlling idle properly (generally idle too low) - ISC

13

(O)

ISC did not respond properly (extends to touch throttle then retracts for KOEO) - ISC

®

Idle Speed Control motor or Air Bypass not controlling idle properly (generally idle too high)

(M)

ISC sticking, open ITS circuit or TP sticking

14

Ignition pickup (PIP) was erratic - Ignition Systems

E4OD Transmission diesel RPM sensor - Diesel RPM sensor

15

(O)

No Keep Alive Memory power to PCM pin 1 or bad PCM (Memory Test Failure)

(M)

KAM (pin 1) was interrupted (was battery disconnected ?)

16

1 9L & 2 5L - Throttle stop set too high - IDLE or Idle Set Procedures

2 3L - RPM's too low - IDLE

(O)

Electronic ignition - IDM circuit fault - Ignition Systems

17

1 9L & 2 5L - Throttle stop set too low - IDLE

18

®

Check base timing & advance function - Timing Tests

(M)

Ignition TACH signal erratic - Ignition Systems

Spark Angle Word (SAW) circuit failure (1 9L SFI)

19

(O)

No Vehicle Power (pins 37 + 57) or bad PCM VPWR Diagnosis

®

Erratic idle during test (reset throttle & retest) - Idle Set Procedures

Electronic ignition Cylinder ID sensor/circuit problem - Ignition Systems

21

Engine Coolant Temperature (ECT) sensor out of range - ECT

22

MAP (vacuum) or BARO signal out of range - MAP

23

Throttle sensor out of range or throttle set too high - TPS

24

Intake Air Temperature (IAT) or Vane Air Temperature (VAT) sensor out of range - IAT VAT

25

Knock sensor not tested (ignore if not pinging) - KS

26

Mass Air Flow (MAF) or Vane Air Flow (VAF) out of range - MAF VAF

Transmission Oil Temperature (TOT) sensor out of range, Transmissions

27

Vehicle Speed Sensor problem - VSS

28

Vane Air Temperature (VAT) sensor out of range - VAT

2 3L w/Electronic Ignition - Cyl ID, IDM low or right coil pack failure - Ignition Systems

29

Vehicle Speed Sensor problem - VSS

31

(O,R,M)

EVP - EVP signal is/was out of range - EVP

(O,R,M)

EVR - EVP signal is/was low - EVR

(O,R,M)

PFE - PFE signal is/was low - PFE

32

®

EVP - EGR not responding properly during test - EVP

(O,R,M)

EVR - EVP signal is/was low - EVR

(R,M)

PFE - PFE shows low pressure, EGR not seating or memory, not seating intermittently - PFE

33

(O,M)

ALL - EGR did not open/ respond during test or if memory code, did not open intermittently - EVP EVR PFE

34

®

EVP - EGR did not respond properly during test - EVP

(O,R,M)

EVR - EVP sensor is/was high - EVR

(O,R,M)

PFE - PFE sensor is/was out of range - PFE

35

®

EVP - Engine RPM's too low to test EGR system - EVP

(O,R,M)

EVR - EVP sensor signal is/was high - EVR

(O,R,M)

PFE - PFE sensor signal is/was high - PFE

38

Idle Tracking Switch signal was intermittent - ISC

39

Transmission Torque Converter clutch not engaging - Transmissions

41

®

System lean - Fuel control

(M)

System was lean for 15 seconds or more (no HO2S switching) - Fuel control

42

®

System rich - Fuel control

(M)

System was rich for 15 seconds or more (no HO2S switching) - Fuel control

43

®

HO2S sensor not reading (run at 2000 rpm's for 2 minutes and retest - check for HO2S switching)

(M)

Was lean at WOT for 3 seconds or more - Fuel control

44

AIR system inoperative - Air Injection

45

AIR not Diverting (AIRD) - Air Injection

Electronic Ignition - coil primary circuit failure - Ignition Systems

46

AIR Bypass (AIRB) not working - Air Injection

Electronic Ignition - primary circuit failure coil 2 - Ignition Systems

47

Low flow unmetered air (check for small vacuum leaks, injector o'rings, gaskets etc )

E4OD transmission 4x4 switch/circuit problem - Transmissions

48

High flow unmetered air (check for large vacuum leak, inlet hoses etc )

Electronic Ignition - coil primary circuit failure - Ignition Systems

49

Electronic Ignition - spout signal circuit problem - Ignition Systems

Transmission 1/2 shift problem - Transmissions

51

Engine Coolant Temperature (ECT) sensor signal is/was too high - ECT

52

Power Steering Pressure Switch/circuit open - PSP

®

Did you turn wheel during test ?

53

Throttle Position sensor too high - TPS

54

Intake Air Temperature (IAT) or Vane Air Temperature (VAT) signal high - IAT VAT

55

No or low (under 7 5 V) Key Power to PCM pin 5

56

Vane Air Flow (VAF) or Mass Air Flow (MAF) sensor high - VAF MAF

Transmission Oil Temperature sensor too high - Transmissions

57

Intermittent in Park/Neutral/ Switch or Neutral Pressure switch circuit - PNP or Transmissions

58

Idle Tracking Switch (ITS) signal problem ISC

Vane Air Temperature (VAT) sensor out of range or open - VAT

59

AXOD 4/3 circuit fault - Transmissions

3 0L SHO - Low speed fuel pump circuit problem - Power / Fuel Pump Circuits

Transmission 2/3 shift problem - Transmissions

61

Engine Coolant Temperature (ECT) sensor is or was too low - ECT

62

AXOD (KOEO only) 3/2 circuit short to ground - Transmissions

AXOD (KOEO AND KOER) 4/3 circuit failure - Transmissions

E4OD excessive converter clutch slippage - Transmissions

63

Throttle Position Sensor (TPS) signal too low TPS

64

Intake Air Temperature (IAT) or Vane Air Temperature (VAT) signal low or grounded - IAT VAT

65

Check intermittent HO2S (signal or ground) - Fuel Control

®

E4OD truck - cycle OD cancel switch after engine ID is received - Transmissions

1984 3 8L ONLY - O, M Battery voltage high (check for electrical system overcharging)

66

Vane Air Flow (VAF) or Mass Air Flow (MAF) signal low - VAF MAF

Transmission Oil Temperature (TOT) signal low (possibly grounded) - Transmissions

67

Park/Neutral circuit fault - PNP

Transmission Manual Lever Position (MLP) sensor circuit - Transmissions

(M)

Intermittent Park Neutral Position (PNP) sensor fault - PNP

68

Idle Tracking Switch (ITS) circuit (possibly grounded) - ISC

Vane Air Temperature (VAT) sensor out of range or grounded - VAT

3 8L AXOD -Transmission Temperature Switch (TTS) open - Transmissions

Electronic Transmission - Transmission Oil Temperature (TOT) sensor was overheated -Transmissions

69

AXOD transmission (O) 3/2 switch closed (possible short circuit) - Transmissions

AXOD (M) 3/2 switch open (poss short to power) - Transmissions

E4OD 3/4 shift problem - Transmissions

70

(M)

3 8L AXOD - Data link to instrument cluster fault Service any other EEC codes, erase memory and retest If code is still present refer to instrument cluster diagnosis manual

71

(M)

1 9L TBI, 2 3L TBI, 2 5L TBI - ITS signal was grounded when throttle should have been opening ITS-ISC ISC motor problem or Idle Tracking Switch (ITS) signal wire shorted to ground - ISC

(M)

1 9L MFI - PCM re-initialized Possible electrical noise, case ground or intermittent VPWR problem - VPWR Diagnosis

(M)

3 8L AXOD - Data link to instrument cluster fault - See code 70

72

®

No MAP or MAF change in "goose" test - retest, check for frequency or voltage change - MAP MAF

(M)

1 9L MFI - VPWR circuit to PCM was intermittent - VPWR Diagnosis

(M)

2 3L T/C - PCM re-initialized Possible electrical noise, case ground or intermittent VPWR problem - VPWR Diagnosis

(M)

3 8L AXOD - Message center data link circuit fault - See code 70

73

(O)

Rerun test, if 73 is still output replace TPS

®

No Throttle Position Sensor (TPS) change in "goose" test Must get at least 25% throttle rotation - TPS

74

Was brake depressed after engine ID was received ?

Brake On Off (BOO) signal open or short to ground - BOO

75

Brake On Off (BOO) signal shorted to power - BOO

76

Vane Air Flow (VAF) did not respond to "goose" test - VAF

77

System did not receive "goose" test - see TESTS

78

(M)

VPWR circuit to PCM was intermittent or the PCM is bad VPWR Diagnosis

79

A/C is on or pin 10 is shorted to power

81

Boost control solenoid - Solenoids

AIRD solenoid - Solenoids and Air Injection

3 0L SHO - Inlet Air Solenoid - Solenoids

82

2 3L TC - Fan Control wire shorted to ground - A/C and Fan Circuits

AIRB solenoid - Solenoids and Air Injection

3 8L SC - Super Charger Bypass Solenoid - Solenoids

83

High Electro Drive Fan circuit fault - A/C and Fan Circuits

EGR Control solenoid - Solenoids

3 0L SHO - Low Speed Fuel Pump Relay circuit - Power / Fuel Pump Circuits

84

EGR Vacuum Regulator - Solenoids

EGR cutoff solenoid - Solenoids

EGR Vent solenoid - Solenoids

85

2 3L T/C Automatic - 3/4-4/3 Shift solenoid - Transmissions

CANP solenoid (ALL 1989) - Solenoids

(M)

1 9L MFI - System has corrected rich condition - Fuel control

86

2 3L or 2 9L Truck - A4LD 3/4 shift solenoid - Transmissions

(M) 1 9L MFI - System has corrected lean condition - Fuel control

87

(O)

Fuel pump circuit fault (check inertia switch) - Power / Fuel Pump Circuits

Vehicles with 2BBL carb - Temperature Compensated Accelerator Pump Solenoid - Solenoids (M) intermittent in fuel pump primary circuit - Power / Fuel Pump Circuits NOTE: On some Escorts with automatic seat belts this code is normal IN MEMORY due to the wiring

88

Throttle Kicker Solenoid - Solenoids

Variable Voltage Choke relay circuit fault - VVC

Fan Control circuit fault - A/C and Fan Circuits

A4LD - Converter Clutch Override solenoid - Transmissions

Electronic Ignition - IDM, DPI or spout circuit fault - Ignition Systems

89

A4LD - Converter Clutch Override solenoid - Transmissions

AXOD Torque Converter Control solenoid circuit - Transmissions

Exhaust Heat Control (heat riser) solenoid circuit - Solenoids

91

(R, M) System running lean - Fuel control

Transmission SS 1 circuit/solenoid problem - Transmissions

92

®

System running rich - Fuel control

Transmission SS 2 circuit/solenoid problem - Transmissions

93

(O,R)

Throttle linkage binding or bad ISC motor ISC HO2S not reading Fuel control

Transmission TCC circuit/solenoid problem - Transmissions

94

AIR system inoperative - Air Injection

Transmission TCC circuit/solenoid problem - Transmissions

95

(O)

Fuel pump: open, bad ground or always on - Power / Fuel Pump Circuits

®

AIR not Diverting (AIRD) - Air Injection

(M)

Possible bad fuel pump ground or open between fuel pump and pin 8 at PCM (Fuel Pump Monitor signal) - Power / Fuel Pump Circuits

96

(O)

Fuel pump monitor circuit shows no power - Power / Fuel Pump Circuits

®

AIR Bypass (AIRB) not working - Air Injection

(M)

(Service 87 code first if present) Fuel pump relay or battery power feed was open - Power / Fuel Pump Circuits

97

E4OD OD cancel light circuit failure - Transmissions

98

®

Did not pass KOEO yet (Get 11 in KOEO first)

Transmission EPC circuit/solenoid failure - Transmissions

99

®

ISC needs to learn (Let idle for 2 minutes, Erase memory and retest)

Transmission EPC circuit/solenoid failure - Transmissions

 

[firelt90bronco]

What does all this mean in dumb dumb terms.

 

[bobstrat]

well the koer

21 coolant temp sensor is out of range- i would take that to mean your sensor is beat.

31 (O,R,M) EVP - EVP signal is/was out of range - EVP

(O,R,M) EVR - EVP signal is/was low - EVR

(O,R,M) PFE - PFE signal is/was low - PFE

i have no idea what 31 means.

41 system lean - fuel control bad fuel pressure regulator maybe? something else that would cause a lean condition? maybe tied in with the 31?

52 Power Steering Pressure Switch/circuit open - PSP

25 Knock sensor not tested (ignore if not pinging) - KS

 

[bobstrat]

evr and evp now you got me thinking about it, arent they the little doo dads by the ignition coil, part of the vacuum tubing stuff, the two little black plastic, i dont know if theyre vacuum switches or what, but they have the round caps on them?

 

[firelt90bronco]

Could the lean mix be caused by the distributor being turned too far? I had to pull the distributor to install the ICM.

 

[Yardape]

Timing doesnt have anything to do with the lean condition. I'd focus more toward the fuel pressure regulator. Or the possibility of plugged/restricted injectors

 

[wtfdissux]

is the O2 sensor old ....could be sending a false lean code

also the ect may cause this by reporting incorrect temp and sending into closed or open loop at the wrong time

and the solenoids by the coil are the tab and tad solenoids and on some the egr solenoid

main thing is to repair/ diagnose and repair them in the order that they come up in and clear them after each repair is made then drive and see what happens as the ford obd1 had a good ability of compensating for problems and would cover for bad info ....meaning that one code will cause the pcm to do something based on all other signals sometimes sending "false codes " that will only go away when the real code is fixed so start with hard or constant codes first then do them in the order they come in

 

[firelt90bronco]

Tomorrow I'll take the o2 sensor out and clean it and then take the vacuum line off the fuel pressure regulator.

 

[wtfdissux]

would rec changing the ect while at it when they go can cause real bad mpg and cold weather running and try cleaning the IAC and throttle body and egr body and tube really good might want to try the sea foam bit if it runs long enough to burn it off

am gonna take a quick look at some of my notes I remember something about the evp/pfe also have fun on the regulator they are a pain in the a&* with upside down allen or torx head and not much room to use anything but a bit in a wrench

 

[Yardape]

is the O2 sensor old ....could be sending a false lean codealso the ect may cause this by reporting incorrect temp and sending into closed or open loop at the wrong time

and the solenoids by the coil are the tab and tad solenoids and on some the egr solenoid

main thing is to repair/ diagnose and repair them in the order that they come up in and clear them after each repair is made then drive and see what happens as the ford obd1 had a good ability of compensating for problems and would cover for bad info ....meaning that one code will cause the pcm to do something based on all other signals sometimes sending "false codes " that will only go away when the real code is fixed so start with hard or constant codes first then do them in the order they come in

What he says makes a ton of sense, check that out for sure

 

[wtfdissux]

EGR Valve position sensor

egr/evp is attached to the egr valve to produce a signal indicating to the EEC-IV system the exact position of the egr valve

check:

disconnect theelectrical connector on the evpsensorand check for reference voltage from the computor with the key on but not runningthere should beapprox. 5.0 volts

next check the resistance of the evpsensor. working on the sensor side check the resistance of the evp and vref. it should be approx. 5,000 ohms.

now apply10 in.hg.of vacuum and checkthe resistance it should be approx. 100 ohms watch for a decrease in resistance as vacuum is applied

yes this may also cause the 41 code along with the ect code

if problems are on the wire side check for breaks etc. if on the evp side replace the evp and thouroly clean the egr valve or replace it clear codes and proceed to next if they reappear after test drive (might need to drive for a few days)

 

[miesk5]

I agree w/wtfdissux, on the EVP, good job man! Some info to complement his info from my notes; the evp works like a throttle position sensor, going from high resistance (5500 ohms) when the EGR valve is closed to low resistance (100 ohms) when it is open

some more info on the DTCs;

21 ECT (Engine Coolant Temp) out of range. Coolant is less than 50degF for KOEO, or less than 180 deg F for KOER, or greater than 250degF for either. If coolant temp is in proper range, suspect ECT sensor. (It won't be, for KOER tests on cars that have a 160degF thermostat)

52 PSPS (Power Steering Pressure Switch) circuit open. Suspect PSPS, harness, or as someone wrote (can't see his identity or comment now in the "Reply" mode); 52® Steering wheel not turned during test or PSPS problem

31 info by Henry G; This code could be caused by several different factors

If the pintle position sensor (Ford calls it the EVP sensor) is shorted or open, you could have a code set.

If the EGR valve becomes carboned up and does not seat fully, the EVP sensor gives a high reading and a code is set.

If the diaphragm of the EGR valve is bad, then it, too, is flagged.

The fix

On Fords and Mazdas, the only sure fix is to replace the sensor and valve as an assembly. Sometimes you can get temporary relief by filing down the pintle sensor stem to lower the sensor return voltage to specs. Or you could add a thicker gasket between the valve and sensor. You can spend a lot of time trying to capture the intermittent failure in the act. This is not recommended. The codes are rarely false. Note that there are two interchangeable sensors; one is gray and the other is black. Key-on-engine-off (KOEO) voltage for the gray sensor is 0.40 volt and for the black sensor is about 0.83 volt. Don't mix them up, or Code 31 won't go away.

41 Check for leaking fuel injector and/or excessive fuel pump pressure

what else did i miss? can't see your DTC List post now, so will look @ your original post that started this later.

 

[firelt90bronco]

Okay, the fuel pressure at the Schrader valve is 33 with a new pump and filter. I suspect the fuel pressure regulator may not be open all the way to deliver adequate pressure.

 

[wtfdissux]

for 52 PSPS (Power Steering Pressure Switch) circuit open was the steering wheel turned when promted and does your truck have a presure switch on the presure line but honestly I would not wory so much on that until the other ones are gone

also check fuel laekdown by attaching presure gage start engine then shut off record the number and leaving the gage hooked up wait an hour or so and see if it droped

 

[firelt90bronco]

I just cleared the codes and no check engine light!!!! I took her for a ride around the block and it seems fine except for a slght pull from a low tire. Now all thats left is time it completely and its great again!

 

[bobstrat]

the greatest reward of all

the check engine light out.