93 sierra error code 32 will not reset

Hi Joe

Like all solenoid valves, you can clean them with throttle body cleaner and then test the solenoid electronically with a 12 volt supply.

P0401 Exhaust EGR Flow Insufficient

Toyota Nation Forum https://www.toyotanation.com > threads > p0401-exha...
May 1, 2014 - The sensor is how the ECM determines there's insufficient EGR flow. It's on the intake-side of the system and if not enough exhaust-gases flow ...

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P0401 : EGR Flow Insufficient on 1996 Toyota Corolla

OBD-Codes.com https://www.obd-codes.com > forums > viewtopic
Jan 20, 2007 - on EGR codes, we recommend replacing the EGR, vacuum modulator and VSV (if equipped) and cleaning out the carbon buildup to the intake from the ...
If that finds nothing wrong, remove the EGR valve and bypass tube and check them for cleanliness and blockages. If they are blocked, follow your maintenance manual's instructions for cleaning them out so you do not damage the valve, then replace them and reset the ECM.

Insufficient EGR Flow - P0401 Code - Toyota

code p 0403 refers to EGR --circuit malfunction===causes --wiring---EGR solenoid --ECM
replacing the valve probably not the problem as there is a separate solenoid to work the valve and that is what is listed in the probable causes
then you have to consider the wiring and connections to the unit

causes include --hose leakage / blockage, basic setting not carried out ( if applicable)--wiring---EGR valve ---EGR solenoid ---ECM

code p 1400 refers to exhaust gas recirculation (EGR) system or evaporative emission (EVAP)canister purge system===causes--wiring---EGR or EVAP valve or ECM
the valve in the EGR may be faulty and bot the solenoid or the problem could be in the EVAP side

have you removed the egr and checked for plugged in the egr port or damage to the egr itself... i think it's more of a flow issue associated with the position of the egr and not the solenoid itself... koeo/koer tests are a pain even with a break out box... good luck as this year (early 90's) of Ford's are the worst for diagnosing computer/running issues

Error Code: P0130
Fault:
Oxygen Sensor (O2S) 1, Bank 1 - Circuit Malfunction
Possible Cause:
Malfunction Indicator Lamp (MIL) Triggered on first occurrence.
-Wiring harness.
-Oxygen sensor (O2S).
-Engine control module (ECM).

Error Code: P0505
Fault:
Idle Speed Control (ISC) System - Malfunction
Possible Cause:
-Wiring harness.
-Idle speed control (ISC) actuator/Idle air control valve (IAC) valve.
-Throttle motor.
-Throttle valve tight/sticking.
-Engine control module (ECM).

Error Code: P0100
Fault Location:
-Mass Air Flow (MAF) Sensor/Volume Air Flow (VAF) Sensor - Circuit --Malfunction
Possible Cause:
-Wiring harness.
-Mass air flow (MAF) sensor.
-Volume air flow (VAF) sensor.
-Engine control module (ECM).

Error Code: P1491
Fault:
Exhaust Gas Recirculation (EGR) Valve Insufficient Lift
Possible Cause:
-Wiring harness.
-EGR Valve.
-ECM

Error Code:P1607
Fault:
-Engine Control Module (ECM)/Powertrain Control Module (PCM)

Error Code: P0966
Location:
-Pressure Control (PC) Solenoid B - Circuit Low
Possible Cause:
-Wiring short to earth.
-Pressure control (PC) solenoid.
-Engine control module (ECM)/Powertrain control module -(PCM)/Transmission control module (TCM) .

You don't say what the make model and year is, but a faulty EGR valve could cause the problem you describe. If the EGR sticks open you would have a large vac leak.

CODE 12- NO DISTRIBUTOR REFERENCE PULSES ECM. CODE 13- OXYGEN CIRCUIT. CODE 14- COOLANT SENSOR HIGH TEMP CODE 15- COOLANT SENSOR LOW TEMP. CODE 21 - THROTTLE POSITION SENSOR VOLTAGE HIGH.CODE 22 - THROTTLE POSITION SENSOR VOLTAGE LOW.CODE - 23 MIXTURE CONTROL SOLENOID.FOR CARBURETOR ENGINE. CODE 24 -VECHICLE SPEED SENSOR. CODE 32 - BARO CIRCUIT LOW.CODE 32 - FUEL INJECTED EGR VALVE VACUUM SWITCH SHORTED TO GROUND.OR EGR VALVE SOLENOID CIRCUIT OPEN. CODE 33 - MAP SENSOR.CODE 34 - VACUUM SENSOR OR MAP SENSOR.CODE 35 - IDLE SPEED CONTROL. CODE 41 - EST CIRCUIT. CODE 42 - ELECTRONIC SPARK TIMING.CODE 43 - ELECTRONIC SPARK CONTROL UNIT. CODE 44 - LEAN EXHAUST.CODE 45 - RICH EXHAUST. CODE 51 - PROM OR MEM CAL.CODE 52 - CALPAK. CODE 53 -EGR VALVE CARBURETED ENGINE THE EGR VALVE VACUUM SENSOR HAS RECEIVED IMPROPER EGR VACUUM. CODE 54 - M C SOLENOID CARBURETED ENGINE MIXTURE CONTROL SOLENOID SHORTED OR FAULTY ECM.CODE 54- FUEL INJECTED ENGINE FUEL PUMP VOLTAGE IS LOW.CODE 55 - ECM MAKE SURE PCM GROUND CONNECTIONS ARE TIGHT.IF OKAY.REPLACE THE ECM.

Problem Description: Code 32 means that the EGR diagnostic switch was not detected closed under the following conditions:

• Coolant temperature greater than 80 C (176 F).
  
• EGR duty cycle commanded by the ECM is greater than 50%.
  
• Manifold pressure less than 25 kPa, (7" vacuum).
  
• All conditions above must be met for about 8 seconds.

Diagnostic Aids: A Scantool can be used to check the diagnostic switch circuit. The Scantool should display "on" when vacuum is applied to the diagnostic switch. The switch should also be indicated as being closed whenever the ECM is commanding an EGR duty cycle of greater than 50%. EGR duty cycle can also be monitored by a Scantool.



"Scan" Diagnostics: Before using this test, check for ported vacuum to EGR solenoid, also check hoses for leaks or restrictions. There should be at least 7"hg vacuum at 2000 rpm.
Disconnect EGR solenoid vacuum harness. Rotate harness and reinstall only the EGR valve side. Ignition on, engine stopped. Install a hand held vacuum pump with gauge to mainfold side of EGR solenoid. Apply vacuum and observe EGR valve, the valve should not move.
Valve does not move Valve moves

You should have your battery checked, it may be getting old and doesn;t have as much cold cranking power, I don;t think code 32 has anything to do with the slow cranking when cold.


Trouble Code 32 indicates that the Exhaust Gas Recirculation (EGR) valve diaphragm is not where the ECM expects it to be. The ECM controls the diaphragm with a Pulse-Width Modulated (PWM) waveform. The EGR has a vacuum bleed solenoid that adjusts the vacuum applied to the EGR valve based on this pulse width. If there is sufficient vacuum at the EGR valve, a switch closes to send a signal back to the ECM. The absence of this signal is the bases for code 32.
The conditions for setting this code are:

• no vacuum to EGR (switch open), and
• Code 33 or 34 (MAF error) is not present, and
• engine running and LV8 is less than 100, and
• coolant temperature is > 118 deg F (48 deg C), and
• the EGR solenoid duty cycle is < 65%, and
• the above conditions are met for more than 25 seconds

Typical causes for this code include:
1) Faulty EGR valve-to-ECM connection
2) Plugged EGR passages and/or sticking EGR valve
3) Defective EGR valve
4) Defective ECM