5.8L Windsor Dying At Red Lights

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YtHeat

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I have a 95 5.8L that is dying at red lights. It runs great with the throttle open, but idle is bad after it warms up. I have so far replaced;

1. Idle Air Control Valve
2. MAP Sensor
3. EGR Valve Control Solenoid
4. O2 Sensor

I also checked for vacuum leaks and haven't found any. All the tubing seems to have been replaced recently before I bought it.

Any direction would be welcomed!
 

miesk5

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Yo YtHeat,
Welcome!
E4OD Transmission Control Indicator Light (TCIL) is a LED with an overdrive on/off switch at end of the Transmission shifter stalk; flashing OD light is an indication of a transmission related trouble code in the Powertrain Control Module (PCM).
The transmission control switch is a momentary contact switch. When the switch is pressed, a signal is sent to the powertrain control module (PCM) (12A650). The powertrain control module then energizes the transmission control indicator lamp and the coast clutch solenoid, applying the coast clutch to provide engine braking and cancels fourth gear operation; does it cause the lamp to glow?
The TCIL indicates overdrive cancel mode activated (lamp on), electronic pressure control circuit shorted or monitored sensor failure (lamp flashing).


Try a Self Test for Diagnostic Trouble Codes (DTC)s by my pal, BroncoJoe19 @ Code Reader

PCM stores the Self-Test program in permanent memory. When activated, Self-Test checks the EEC system by testing memory integrity and processing capability, and verifies that various sensors and actuators are connected and operating properly.


The engine temperature must be greater than 50° F for the Key On Engine Off (KOEO) Self-Test and greater than 180° F for the Key On Engine Running (KOER) Self-Test. Run it around to heat the engine up and shift thru all gears including Reverse. Make sure A/C is off and transmission is in Park (automatic); or in Neutral for a Manual & release clutch. Then turn off engine, all accessories/lights (close driver's door) , etc.

Do KOEO test First. Post Code(s) here according to KOEO & KOER.
A helper can assist you by counting the codes. Some use their smart phones to record them.

BEWARE OF FAN, BELTS, PULLEYS, HOT HOSES, IGNITION HIGH TENSION WIRES, AND ENGINE COMPONENTS

Or ask local mom and dad parts stores if they will test it for you.
Or purchase a coder reader such as Equus 3145 Innova OBD I Code Reader for Ford EEC IV Engines at Walmart & most parts stores.

Vacuum leak tip; if the leak exists in an accessory unit, such as the power brake, the unit will not function correctly. Or Air Conditioning when in MAX mode may switch to Defrost.

See my Vacuum leak test in post #11; includes jowens126 's HVAC Control Panel info & Mikey350's tests @ https://www.fullsizebronco.com/threads/help-with-dtc-codes-and-idle.206824/



ASAP, find out if speed control recall work, if equipped was completed. If you still have concerns about Recalls, please contact the Ford Customer Relationship Center:
US: 800-392-3673 | CA: 800-565-3673
Note: 3673 spells "FORD" on phone keys
For the hearing- or speech-impaired: Please contact the Telecommunication Relay Service by dialing 71
"Summary: ON CERTAIN PICKUP TRUCKS, PASSENGER VEHICLES, SPORT UTILITY VEHICLES, AND MOTOR HOMES CHASSIS, THE SPEED CONTROL DEACTIVATION SWITCH MAY, UNDER CERTAIN CONDITIONS, LEAK INTERNALLY AND THEN OVERHEAT, SMOKE, OR BURN. THIS COULD RESULT IN AN UNDERHOOD FIRE."
See this guide by jowens1126 to confirm recall status @ 93 & 94-96 Cruise Control Recalls Repair
Note that the 93 recall is different than 94-96.

1995 Bronco Dealer Brochure @ 1995 Ford Bronco

1995 Bronco Drivetrain, Powertrain Service Manual - Google Drive
&
1995 Bronco Chassis, Service Manual - Google Drive
To switch between folder list & grid views, click the button to the right of the "DOWNLOAD ALL" button in the upper right corner of the window) by HawkDriver

Haynes Red Manual for 80-95 Bronco & F Series @ Hanes guide 80-96 bko f series.pdf via BroncMom
Al
 

Tiha

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You said EGR sensor. I believe you can loosen the EGR valve and slip a quarter behind it to block it off for testing purposes.
1995 is still speed density, so no check engine lights? or codes?
 
OP
OP
Y

YtHeat

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You said EGR sensor. I believe you can loosen the EGR valve and slip a quarter behind it to block it off for testing purposes.
1995 is still speed density, so no check engine lights? or codes?
Codes:
121 - Throttle Position (TP) sensor out of range – TPS
334 - EVP sensor is/was high – EVR
558 - EGR vacuum regulator solenoid/circuit failure – EVR or PFE or Solenoids
173 - Oxygen sensor not switching – system is or was rich – Single, Right or Rear HO2S – Fuel control
332 - EGR did not open/respond during test or if memory code, did not open intermittently – EVR or PFE
 

miesk5

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Yo Y,
121 - Throttle Position (TP) sensor out of range – TPS
DTC 121, 122, 123, 124, 125 & P0122 and P0123 in TSB 94-26-4 "...The following is a list of vehicle symptoms which have been associated with the TPS, but can also be related to other vehicle components. Check engine light, ➡Stalls, quits, hesitation/stumble, fast idle; To minimize the replacement of good components, be advised that the following non-EEC areas may be the issue: Excessive blow-by, PCV malfunction, Vacuum leaks, Fuel pressure, Throttle sticking or linkage binding. MANY VOLTMETERS WILL AUTOMATICALLY CHANGE RANGES WHEN MEASURING TPS OUTPUT FROM IDLE TO WOT. WHEN A VOLTMETER IS USED TO MEASURE TPS OUTPUT FROM IDLE TO WOT, THE METER SCALES OR CHANGES RANGES AUTOMATICALLY. THERE MAY BE AN ERRONEOUS METER DISPLAY UNTIL THE VOLTMETER HAS LOCKED TO THE APPROPRIATE VOLTAGE READING. THE ERRONEOUS METER DISPLAY DOES NOT REPRESENT A DEFECTIVE TPS. NOTE: IT IS RECOMMENDED THAT THE "RANGE LOCK" FEATURE ON MANY METERS BE SET FOR CHECKING TPS VOLTAGE..."

SEE Throttle Position Sensor Testing & Management @ Bronco Forum - Full Size Ford Bronco Forum by by Seattle FSB
See my Vacuum leak test in post #11 incl jowens126 's HVAC Control Panel info @ Help with dtc codes and idle

334 - EVP sensor is/was high – EVR
DTC 334 EGR (EVP) in either KOEO = Key On Engine Off, or CM = Continues Memory, or KOER = Key On Engine Running indicates a closed valve voltage higher than expected; "...Failed sensor, & as rla2005 (Randy) wrote; carbon between EGR pintle valve and seat holding the valve off its seat. Remove the EGR valve and clean it with carbon remover. Prior to re-installing see if you can blow air through the ****** side of the EGR by mouth. the egr is not closing properly which can cause detonation. remove the egr and clean off any carbon built up on it with carb cleaner and a brush if necessary. The EGR Valve Position (EVP) Sensor used exclusively by Ford, can be the cause of driveability problems without ever setting any trouble codes. The relationship between the EVP sensor and the EGR valve is important to understand. Either one being out of spec can cause similar symptoms. Understanding this relationship will help you to diagnose uncoded driveability problems like stumbles, hesitations, rough idles and stalling..."
Source: by rla2005 (Randy) at FSB
View attachment 177969

View attachment 177970
Testing; "...There shouldn't be any vacuum at the EGR valve at idle or any time your ass is under the hood fiddling with it, to put it plainly, except for perhaps a very light residual vacuum from the EVR. Check ALL of your vacuum lines FIRST, and the vacuum reservoir for leaks..."
Source: by SigEpBlue (Steve) at FSB


558 - EGR vacuum regulator solenoid/circuit failure – EVR or PFE or Solenoids
And a lot of Ford's PCED/EVTM pin-point testing revolves around the BO Box settings, such as;
"...DTC 558: indicates a failure in the EGR Vacuum Regulator (EVR) solenoid circuit/Damaged EVR solenoid; Open harness, Shorted harness, Damaged Powertrain Control Module (PCM). ;
Install breakout box, leave PCM disconnected. Measure resistance between Test Pin 33 at the breakout box and EVR circuit at the EVR solenoid vehicle harness connector. Is resistance less than 5.0 ohms?
No - SERVICE open circuit. REMOVE breakout box. RECONNECT all components.RERUN Quick Test.
Yes - GO to DN13.
DN13 CHECK EVR CIRCUIT FOR SHORT TO POWER OR GROUND. Key off. EVR solenoid disconnected.
Breakout box installed, PCM disconnected. Measure resistance between Test Pin 33 and Test Pins 37 and 57 at the breakout box. Measure resistance between Test Pin 33 and Test Pin 40, 46 and 60 at the breakout box.
Is each resistance greater than 10,000 ohms?
No - SERVICE short circuit. REMOVE breakout box. RECONNECT all components. RERUN Quick Test. If DTC is repeated, REPLACE EVR solenoid.
Yes -REPLACE PCM. REMOVE breakout box. RECONNECT EVR solenoid. RERUN Quick Test.."
Source: by Ford via miesk5 at FSB
as I mentioned in another thread here; In place of the breakout box, go to the EEC pin instead; for instance - Measure resistance between Test Pin 33 and Test Pin 40, 46 and 60 at the breakout box. Substiture EEC for :breakout box"
EEC Connector Pin Diagram & Overview by Ryan M (Fireguy50) at http://web.archive.org/web/20131229163930/http://oldfuelinjection.com/images/eec04.gif

EEC Connector Pin LEGEND, Bronco & Ford Truck & Van: 4.9, 460, 5.0, 5.8;
Source: by Ryan M (Fireguy50) at Ford Fuel Injection
In front of the TAB/ TAD Solenoids is the EGR Vacuum Regulator (EVR); also called EGR Vacuum Solenoid
It 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)
tab-tad-evr-coil2a.jpg
Location pic by SeattleFSB (Seattle FSB)
The most common problem with the EVR is for its vacuum line to crack. Simply slip rubber vacuum line over the breakey
Static Resistance Values:
TAB/TAD: 50-100 ohms
EVR: 30-70 ohms
 

miesk5

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Yo,
AFTER SPENDING a LONG TIME ON THIS, AN ERROR MESSAGE STOPPED ME FROM POSTING BECAUSE I had MORE THAN 10K CHARACTERS!
173 - Oxygen sensor not switching – system is or was rich – Single, Right or Rear HO2S – Fuel control
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 Source: by Ryan M (Fireguy50)

For now, ignore tsbs as you have inspected harness...
DTC 172, 173 or 41 for HO2S Failure, in POSSIBLE LOCATIONS OF WIRING SHORTS TSB 95-02-11 for 92-95 Bronco & F Series; "the HO2S wires in the 12A690 (subassembly of the 14B060 battery cable) harness may be cut on the lower right engine mount causing improper signals to be sent to the PCM. Damage may be under the electrical tape..."

DTC 172, 173 or 41 for HO2S Failure Or Fuse \"E\" Inoperative, ABS Light On, Back-Up Lamps Inoperative, Daytime Running Lamp (DRL) Inoperative, MIL On, Inadvertent Self-Test, Speedometer Inoperative & Trailer Battery Charge Relay Inoperative in TSB 95-5-21 for 92-95 Bronco & F Series; "...the HO2S wires in the 12A690 (subassembly of the 14B060 battery cable) harness may become chafed and the vehicle could exhibit any one of the following conditions....Lack of proper HEGO operation may cause, or be the result of a rich or lean fuel condition, which could cause additional heat in the catalyst. Perform self test KOEO and KOER, service any codes. CHECK FOR PROPER HEGO GROUND. If the HEGO ground is good, the following areas may be at fault: ..." READ MORE
Source: by Ford via Steve83 (Steve, That dirty old truck) 1983 Ford Bronco TSBs & FSAs (Recalls) for '83-96 Broncos & F150s picture | SuperMotors.net


DTC 173 Oxygen sensor not switching - system is or was rich - Single, Right or Rear HO2S; "...I'd guess there's either an obstruction in the exhaust pipe directing the exhaust away from it, preventing it from detecting & operating normally (not likely), OR there may be a fault in the heating element circuit (more likely). It comes off the circuit (can't remember which fuse) which also feed A LOT of other things and runs around the front of the radiator to the R side near the battery where it drops down by the engine mount & goes to the sensor. Make sure you have good power & ground to the appropriate terminals in the connector, and test for a signal voltage. Then, using the old & the new sensors, trace the fault..."
Source: by Steve83

DTC 173 in 94 by Ford
Fuel Control
Excerpts...1994 PCED OBDI-A
SECTION 6A: EEC-IV Pinpoint Test
Procedures
H: Fuel Control
H: Introduction

H1 CHECK FOR FUEL DILUTED ENGINE OIL



Diagnostic Trouble Code (DTC) HO2S Orientation Fault Definition
172r
136r
176c right or rear
left or front
left or front system indicates lean
173r
137r
177c right or rear
left or front
left or front system indicates rich
144c
139c right or rear
left or front no HO2S switch
detected
171c
175c right or rear
left or front adaptive fuel limit
reached

Possible Causes:
Fuel injectors.
HO2S.
Secondary Air Injection (AIR) system.
PCV/Hose.
Vacuum.
CANP.
MAP sensor.
Electronic Ignition Coil Failure.
Key off.
Remove the PCV valve from the valve cover. Inspect both rocker cover hole and PCV for damage, sludge build up, blockage and movement of valve plunger. Service as necessary.
Run Key On Engine Off (KOEO) and Key On Engine Running (KOER) Self-Tests.
Address any continuous ignition DTCs before servicing KOER DTCs.
Note: For a No Start, GO directly to H2.
Are any of the above DTCs present in KOER Self-Test?
Yes
REINSTALL PCV valve. GO to H2.
No For Continuous Memory DTCs 139, 144, 171, 176,177 GO to H2
All Others:
CHANGE engine oil and filter. REINSTALL PCV valve

... skipping to ..

H14 CHECK HO2S INTEGRITY
HO2S always lean, slow to switch or lack of switching. Fuel at adaptive limit could be caused by:
Moisture inside the HO2S harness connector resulting in a short to ground.
HO2S coated with contaminants.
HO2S circuit open.
HO2S circuit shorted to ground.
Key off.
Inspect the HO2S harness for chafing, burns or other indications of damage. Service as necessary.
Inspect HO2S and connector for indication of submerging in water, oil, coolant, etc. Service as necessary.
Run engine at 2000 rpm for two minutes.
Key off.
Run Engine Running Self-Test.

Skipping to...
Key off.
Verify MAP sensor output voltage (refer to procedure in Pinpoint Test Step DF3).
Disconnect appropriate HO2S from vehicle harness.
For 4 wire HO2S (refer to schematic):
Connect DVOM to HO2S circuit and HO2S GND or SIG RTN at the HO2S connector.

Skipping to
H24 CHECK HO2S SIGNAL FOR SHORT TO POWER

With dual HO2S, DTC 173 refers to right or rear HO2S; DTCs 137 and 177 refer to left or front HO2S.
HO2S always rich could be caused by:
Moisture inside HO2S harness connector resulting in a short to power.
HO2S circuit shorted to power.
Key off.
Disconnect the suspect HO2S from vehicle harness.
Inspect both ends of the connector for damaged or pushed out pins, moisture, corrosion, loose wires, etc. Service as necessary.
Key on, engine off.
Measure voltage between HO2S circuit and PWR GND at the HO2S vehicle harness connector (refer to schematic).
Is voltage less than 0.5 volt?

Mass Air EFI (Sequential Firing) Overview; "...A mass air sensor directly reads the mass of air (or number of molecules of air). By doing this, it can detect the changes in the volume of air, in addition to it's pressure and temperature. Mass air EFI is usually what is called SEFI (Sequential Electronic Fuel Injection), which has one separate wire for each injector and fires them twice for every power stroke of the engine. This makes the injector timing more accurate and will help emissions along with power..."
You have Speed Density EFI Overview; "...In 1986, Ford switched to EFI on 5.0 Bronco engines. 1987 brought the first EFI 5.8. The EFI Ford used for almost all Broncos is what is called speed density. Speed density EFI uses a manifold absolute pressure sensor (MAP), a throttle position sensor (TPS), an air intake temperature sender (ACT) , and the knowledge of the factory intake/exhaust tract which gives your engine certain volumetric efficiencies over it's RPM range. This allows the EEC-IV (Electronic Engine Control IV) to determine the mass (different than volume) of air coming into your engine, and hence the amount of fuel needed to go with this air. Speed density EFI also uses what is called bank fire injection. 4 injector are fired at one time on each side of the engine (only 2 wires for firing injectors from EEC-IV)...."
Bank Fire & Sequential Firing Overview; miesk5 Note' "... Speed density EFI also uses what is called bank fire injection. 4 injector are fired at one time on each side of the engine (only 2 wires for firing injectors from EEC-IV)...."

Read much more
This set of tests includes use of Ford's old Break-Out Box; so, as I mentioned in another thread here; In place of the break-out box, go to the EEC connector pin instead; Substitute EEC connector pin Number for breakout box number
EEC IV Connector Pin Diagram
Source: by Fireguy50 (Ryan M) at %2Fweb.archive.org%2Fweb%2F201312291...ges%2Feec04.gif
EEC IV Connector Pin LEGEND Bronco & Ford Truck & Van: 4.9, 460, 5.0, 5.8;
Source: by Ryan M (Fireguy50) at http://web.archive.org/web/20120118104425/http://www.oldfuelinjection.com/truckpinouts.html

Also may need to use a parts store's loan-a-tool program for;
Hand held fuel pressure gauge kit
Vacuum gauge
Tachometer
DVOM
Non-powered 12 volt test lamp

See my Vacuum leak test in post #11 @ https://www.fullsizebronco.com/foru...ame-free-zone/206824-help-dtc-codes-idle.html
Excerpts;
One way to do a quick check is to grab a vacuum gauge. Some parts stores will loan you a gauge with refundable deposit.
The vacuum gauge should read between 15 and 22 in-Hg depending upon the engine condition and the altitude at which the test is performed. SUBTRACT ONE INCH FROM THE SPECIFIED READING FOR EVERY 1,000 FEET OF ELEVATION ABOVE SEA LEVEL.
The reading should be quite steady. .
When engine is rapidly accelerated (dotted needle), needle will drop to a low (not to zero) reading. When throttle is suddenly released, the needle will snap back up to a higher than normal figure.

When vacuum leaks are indicated, search out and correct the condition. Excess air leaking into the system will upset the fuel mixture and cause conditions such as rough idle, missing on acceleration, or burned valves. If the leak exists in an accessory unit, such as the power brake, the unit will not function correctly. Or Air Conditioning when in MAX mode may switch to Defrost.

 

miesk5

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One more frigging error!
Wish we were informed of this restriction!!!
332 - EGR did not open/respond during test or if memory code, did not open intermittently – EVR or PFE
A vac leak could cause DTC 332 - Insufficient EGR flow detected
Listen for a hiss; check hose from EVP back to EVR

See my Vacuum leak test in post #11 incl some jowens126 HVAC Control Panel pics/info @ https://www.fullsizebronco.com/foru...ame-free-zone/206824-help-dtc-codes-idle.html

Excerpts: One way to do a quick check is to grab a vacuum gauge. Some parts stores will loan you a gauge with refundable deposit.
The vacuum gauge should read between 15 and 22 in-Hg depending upon the engine condition and the altitude at which the test is performed. SUBTRACT ONE INCH FROM THE SPECIFIED READING FOR EVERY 1,000 FEET OF ELEVATION ABOVE SEA LEVEL.
The reading should be quite steady. .
When engine is rapidly accelerated (dotted needle), needle will drop to a low (not to zero) reading. When throttle is suddenly released, the needle will snap back up to a higher than normal figure.

When vacuum leaks are indicated, search out and correct the condition. Excess air leaking into the system will upset the fuel mixture and cause conditions such as rough idle, missing on acceleration, or burned valves. If the leak exists in an accessory unit, such as the power brake, the unit will not function correctly. Or Air Conditioning when in MAX mode may switch to Defrost.

Possible Causes; "...EGR valve sticking closed
EGR valve diaphragm leaks
EVR solenoid sticking closed
Loss of vacuum to or from EVR
Open in EVR VPWR or driver circuits
Continuous Memory DTC 332 indicates the EGR valve did not open with the engine stabilized and the EVR solenoid duty cycle present sometime during vehicle operation.
Possible causes: "...Obstructed or cracked hose to EGR valve,Icing, Damaged EGR valve, Damaged EVR solenoid harness..."
Source: by Ford via SigEpBlue (Steve)
 

Tiha

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Awesome info there and probably everything you need.
Miesk most likely has it covered.

Two more I will throw at ya. Seems like a couple odd balls we had.

ECT? Engine coolant temp. Seems like we ran into a few of those making it run rich.
Other odd ball possibility is leaking or cracked exhaust manifold.

I think I would focus on TPS first.
 

captsb890

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The idle control valve keeps it running at idle--( pushing air behind the throttle plate )the TPS works with the ECM to position it. So, you're not getting air at idle control valve ( when you come to a stop and the plates are closed inside the throttle body ) The TPS is cheap and a little bother to change but when the throttle control assembly is off (tps is on bottom) clean the assembly good with carb cleaner. With the age of the car ,if the TPS doesn't solve the problem and you did everything else, it's time for a new ECM-----also one other thing, when you start changing sensors if you didn't leave the negative lead off the battery for 10 minutes and drive for about 20 miles, the computer has to reprogram--so be sure if you change the TPS you do this---the TPS is also tied in with the PIP but if you see rpm at start and no check engine light, that is probably ok. I have an 89 Bronco and ever since I had the transmission overhauled it did strange things, drove me crazy. changed everything and still not working good, but even though I didn't get an OBD reading on this--I decided to put my old MSP sensor back in and vola ! --these sensors are cheaply made ---good luck, I know it's frustrating !
 

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