89 bronco 302 self test codes

I ran the self test using a paper clip and got these codes:

KOEO: 33

KOER: 41, 33, 77

I've spent about a week reviewing codes but wanted to know where to start. I plan on checking for vac leaks first but was hesitant of using carb fluid. Is there a safer way to check for leaks? Also sounded like my EGR and O2 sensors might be bad. Plan on changing fuel filter this afternoon. I noticed when it runs there is a heavy exhaust smell. It takes a few cranks to start up and needs gas to get an idle. Once idle is reached she seems to run good. Is there a way to check if EGR is functioning without removal? When I pull my O2 sensor what should I look for? Thanks for any help. I need it.

yo Paul,

DTC 33 is triggered when the EVP sensor is not closing;

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..."
Source: by Harry G

so EZiest & cheapest checks are to inspect & repair/replace repair any bad vac lines. for a <$ vac line test; I pull em off and use the straw sucking test; one finger over one end;

You can use  a local auto parts store loan-a-tool program to "borrow" a hand-held vac pump/meter and accessories for a fully refundable deposit.
Source: by miesk5



EVP & EGR location pic in an 89 5.0 (part of his valve cover and oil pan gasket job); Miesk5 Note EVP is light gray & attached to the top of the EGR Valve
Source: by Waltman at SuperMotors.net

EGR Valve Position (EVP) - MIESK5 NOTE: EVP is used on all years except for 95 5.8L California models & all 96, they use the DPFE Sensor instead of EGR Valve Position Sensor (EVP)

EVP Connector pin-Out Diagram, Testing & Operation; "...The EGR Valve Position (EVP) sensor monitors the position of the EGR valve pintle. The EVP sensor converts the mechanical movement of the pintle into an electrical voltage signal which is relayed to the PCM. The EVP sensor is a linear potentiometer in which resistance varies with the EGR valve pintle movement.Voltage is fed to the EVP by the signal return circuit. As the EGR is opened the EVP directs more voltage to the EEC and less down the voltage reference circuit. The EVP sensor provides the PCM with information on EGR flow and EGR system failures. The EVP should read between 0.24 and 0.67 volts at idle with a closed EGR valve..." read more
Source: by Ryan M (Fireguy50) at

http://web.archive.org/web/20120626164618/http://oldfuelinjection.com/?p=35

Testing & Operation
Source: by Tomco Inc. http://www.tomco-inc.com/Tech_Tips/ttt19.pdf

EGR Vacuum Regulator (EVR); also called EGR Vacuum Solenoid

The EVR is a solenoid with two vacuum ports. One port is connected to a vacuum source/supply, and the other is connected to the EGR valve. There is also a passage that vents vacuum to the atmosphere.

A disc inside the solenoid is moved by electro-magnetic force, as directed by the PCM. If more EGR flow is required, the PCM increases the duty-cycle to the EVR, moving the disc to close off the atmospheric vent, which in turn increases the amount of vacuum flow to the EGR valve. If less EGR flow is desired, the PCM decreases the duty-cycle to the EVR, allowing for more atmospheric venting and hence less vacuum flow to the EGR valve.

The EVR is a "normally closed" solenoid, which means that when it is de-energized, the position of the disc allows for maximum venting to the atmosphere (resulting in negligible vacuum flow to the EGR valve).

Note that Ford EGR systems DO NOT engage when:

1) The engine is cold ;
2 ) The engine is at idle;
3 ) The engine is at WOT;
4) At low ambient temps (water vapor from the exhaust can freeze on the throttle plate).

EVR Location pic


Source: by SeattleFSB

=============
Vacuum Pump Build Plans, DIY; built for less than $20, we call it the "Cheap Little Sucker"
Source: by Jame R and Tim C at http://www.berkut13.com/sucker.htm

Vacuum Pump Build Plans, DIY; convert a tire inflator-type air compressor into a vacuum pump
Source: by drcrash at http://www.instructables.com/id/conv...ressor-into-a/

Vacuum Pump Build Plans, DIY; make a manual vacuum pump for under $20 by converting a bicycle pump
Source: by drcrash at http://www.instructables.com/id/make-a-manual-vacuum-pump-for-under-$20-by-convert/
 

=============

41 CM Right or Rear No HEGO sensor switching detected or disconnected.

DTC 41, 42, 91, 92, 136, 137,139, 144, 171, 172, 173, 175, 176, 177 & some Possible Causes for Rich & Lean HEGO The engine temperature must be greater than 50°F (10°C) to pass the KOEO Self-Test and greater than 180°F (82°C) to pass the KOER Self-Test. To accomplish this, the engine should be at normal operating temperature

All of the following items will cause a HEGO code:
• Check engine oil for fuel contamination.
• Check fuel pressure.
• Check fuel systems ability to hold pressure for 60 seconds.
• Engines general condition.
• Fuel injectors (leaky, stuck, dirty).
• Secondary Air Injection (AIR) system.
• PCV / Hose stuck or blocked.
• Vacuum leaks.
• Fuel Injector O-Rings.
• CANP.
• MAP/MAF sensor.
• Ignition Coil Failure.
• Wiring harness general condition.
• Old HEGO sensors (should be replaced every 60,000 miles).

READ MORE

Abbreviations http://web.archive.org/web/20120114164227/http://www.oldfuelinjection.com/?p=15

Source: by Ryan M (Fireguy50) at http://web.archive.org/web/20120121075626/http://www.oldfuelinjection.com/index.php?p=31

Contaminated Oxygen Sensor pics w/Diagnosis, General
Source: by Tomco
Contamination will make the sensor function inaccurately, which will lead to poor performance, poor fuel economy and high emissions
 

http://cds.activant.com/C2C/C01/68/541/824663110.pdf

WIRING DIAGRAMS from Ford Electrical and Vacuum Troubleshooting Manual (EVTM) Partial, Bronco, F 150 for 86, 89 & 91
by Ford via Ryan M (Fireguy50) at http://web.archive.org/web/20130622040914/http://fordfuelinjection.com/?p=36

here is page 41
 

===========

DTC 77 system failed to recognize brief WOT dynamic resistance test. Need to press gas pedal during KOER; Operator didn't execute WOT when told to during self test.

I'll post this for now and get back with other info in an hour or so.

yo,

Vehicle Emission Control Information(VECI), PUK (49 States) Decal, PGP (Canada) Decal, Vacuum Diagrams & Calibration Parts List for 88 & UP at Ford Dealers:

(need to know your Calibration number off of your PCM or driver B pillar sticker)

 & Emission Parts with Ford MC PN's:

such as FOR EXAMPLE:

NAME/DESCRIPTION ENGINEERING NO. SERVICE NO.

VALVE ASSY., (Thermactor Air By-Pass) E1TE 9B289-GA E1TZ 9B289-C SENSOR, (EGR Valve) E7TF 9G428-AA E7TZ 9G428-A RESERVOIR ASSY., (EGR Vacuum) D5TE 9E453-AA D5TZ 9E453-A CONTROL ASSY., (EGR Vacuum Regulator) E53E 9J459-AA E63Z 9J459-A VALVE ASSY., (Thermactor Air Control Solenoid Vacuum) E7TE 9H465-AA E7TE 9H465-BA Alt. E7TZ 9H465-A E7TZ 9H465-B Alt. SENSOR ASSY., (Exhaust Gas Oxygen) E73F 9F472-AA, BA,CA E73Z 9F472-A SENSOR ASSY., (Manifold Gas Oxygen) E7EF 9F479-A1A,A2A E7FZ 9F479-A VALVE ASSY., (EGR Gas Oxygen) E7TE 9F483-F2A,F4A E6TE 9F483-B2A, B4A Alt. E7TZ 9F483-F E6TZ 9F483-B Alt. PUMP ASSY., (Thermactor) E5TE 9A486-DB E5TZ 9A486-D VALVE ASSY., (Thermactor Check - 3/4-14 Short Connector One End - Hose ****** One End - Upstream)   D4VY 9A487-A VALVE ASSY., (Thermactor Check - Hose ****** Both Ends - Downstream)   E3TZ 9A487-A VALVE ASSY., (Thermactor Control) E47E 9F491-BA E3TZ 9F491-A INJECTOR ASSY., (Fuel) E5TE 9F593-AB,BB E5TZ 9F593-B VALVE ASSY., (Throttle Air By-Pass) E7TE 9F715-F1A E7TZ 9F715-A REGULATOR ASSY., (Fuel Charging Pressure) E6AE 9C968-AB, CA,DA E7EE 9C968-AA Alt. E77E 9C968-AA Alt. E6AZ 9C968-A E7FZ 9C968-A Alt. POTENTIOMETER ASSY., (Throttle Position Sensor) E6TF 9B989-AA E7TF 9B989-CA Alt. E6TF 9B989-A E7TZ 9B989-D Alt. DISTRIBUTOR ASSY.) E5TE 12127-AA E5TZ 12127-A SENSOR ASSY., (Engine Electronic Control Coolant Temperature) E4AF 12A648-AA E1AZ 12A648-A PROCESSOR AND CALIBRATOR ASSY., (EEC-IV) E7TF 12A650-AT1B, AT2B E8TF 12A650-J1A, J2A Alt. E7TZ 12A650-ATB E8TZ 12A650-JA Alt. SENSOR ASSY., (Air Charge Temperature) E4AF 12A697-AA E1AZ 12A697-A SENSOR ASSY., (Engine Spark Knock Intensity) E3AF 12A699-AA E3AZ 12A699-A

Vacuum Line Acronyms, leak test & gauge pic

http://broncozone.com/topic/23994-90-58l-getting-continuous-code-33-and-running-code-44/

see Post #20

Consider Ford Fuel Injection and Electronic Engine Control: How to Understand, Service and Modify, 1988-1993; & Ford Fuel Injection and Electronic Engine Control: How to Understand, Service, and Modify All Ford-Lincoln-Mercury Cars and Light Trucks, 1980 to 1987 by Charlie Probst

avail @ BARNES & NOBLE, AMAZON, E BAY, ETC.

Appreciate all the help. Looks like I was on the right track. Pulled the EGR and it was good. Found one vacuum leak by sound. Think I will rent equipment to check properly. Replaced thermostat and fuel filter yesterday. Ordered new K&N air filter. Looked like someone cleaned the old one with a wire brush. Looking for o2 sensor. Any leads where to find them at a good price.

yo Paul,

YW!

I get the Ford Part Number from VECI as shown above, then gOOGle the heck out of it for pricing.

http://frugalmechanic.com/auto-part/oem-e73f9f472aa-oxygen-sensor?p=frugalmechanic_adcenter&e=adcenterfullhalffixed1%2Fmodel.half#s=bing&m=cpc&c=oem&t=e73f9f472aa

Confirm at

http://www.fordparts.com/Commerce/CatalogResults.aspx?y=1989&m=Ford&mo=Bronco#Search

9F472

(DY604)
Oxygen Sensor
5.0L 302 CID 8 Cylinders; E73F-9F472-AA,BA,CA, E9SF-9F472-BA                $60.55                    
 ================
 
 
I prefer Bosch

Would this work? Got a hook up at autozone.

Went with the Bosch o2 sensor and replaced k&N air filter. Motor is tinning much smoother. After all the reolacements I'm still getting codes 41 and 33 during self test. A friend came over and ran a diagnostic test on 500 dollar computer and no codes were showing? Thinking I still have a vacuum line leak. What exactly is the picture below of? Should it be open Or attached to a vacuum line? Thanks again for all your help miesk5. Also below is a pic of old o2 sensor.

yo Paul,

Sorry, did not see your pics and post until this morning.

Pic on left is the smog pump's muffler; no vacuum at the muffler.



pic by Steve

That Bosch O2 sensor will do the job.

Remember to check under dash for the HVAC vacuum lines and devices.

GL!

Didn't find ant more vac leaks. Looks like previous owner capped heater lines going into passenger side. They are bolted and clamped. Would this trigger a code?

Pauliten02 said:

Didn't find ant more vac leaks. Looks like previous owner capped heater lines going into passenger side. They are bolted and clamped. Would this trigger a code?

Click to expand...

yo Paul,

No, heater lines won't cause a code.  Look on passenger side, firewall/ inner fender liner corner; inspect the Outside Recirculate Air vacuum "motor" & vac line



pic by John M

Vacuum Tank for AC (plastic ball type) Location & Carbon Cannister (Charcoal, Vapor, Evaporative Emission (EVAP) & Vacuum Hose Routing Video in an 86 5.0

Source: by JKossarides ("The Bronco", Jean) at http://www.supermotors.net/registry/media/742200

Vacuum Tank (plastic ball type) Location & Diagram in 80-86 & 92-96; "...80-91 similar, except 87-early 88 w/factory air; The 80-86 vacuum tank is a plastic ball on the R wheelwell..."

Source: by Steve at http://www.supermotors.net/registry/media/741015

Air Conditioning & Heater Vacuum Diagram in 92-96; "...80-91 similar, except 87-early 88 w/factory air..."

Source: by Steve http://www.supermotors.net/registry/media/741015

Look under dash @ vac motors, vac lines and control panel for leaks