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Discussion Starter #1 (Edited)
When I was at a stop sign taking off I noticed I was getting little power. I saw my RPMS go high to about 1500 roughly. I was only going 20 MPH it would not go any faster then that. until I found a safe place to pull over and check what was going on When I did it almost immediately muffled down and died when I put it into park. tried to start it again and nothing waited about 1 hour until the tow man came and it started! But after that it hasn’t started since. I initially thought it was the fuel pump changed that along with the fuel filter and the fuel pressure regulator just going down the list I’m thinking of doing the TPS sensor but before I do lead me into the right direction also my truck will idle for about 2 seconds then dies anytime I apply pressure you the gas appreciate all of your guys help !! :)

79 Posts
Checking for codes would be my first step. When you say you “tried to start it again and nothing,” do you mean no crank or crank but no start? Same question since the tow. Sounds like it’s unlikely fuel related since you replaced the pump and regulator. I’m not sure a bad TPS would cause a no start condition. Depending on your answers to the foregoing, I might take a closer look at the ignition components.

4,661 Posts
A little known behavior of the PCM is the ability to clear a flooded engine. If the engine RPM is less than 150, and the throttle is wide open, the injectors are shut off. This allows a flooded engine to crank without introducing any more fuel. A TPS that is malfunctioning and presents to the PCM a WOT (Wide Open Throttle) signal, could prevent a start, which would look like the engine was not getting any fuel.
Meter the TPS to see if it is working.
(If you ever had a carbureated engine, you would hold the throttle wide open while cranking to clear the engine if flooded, a fuel injected engine should (in theory) never flood.)

Super Moderator
23,882 Posts
Yo Ruggcowboy,
As Petersonat advised, 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.

Inspect the air cleaner and inlet ducting. Check all engine vacuum hoses for damage, leaks, cracks, blockage, proper routing, etc. Check EEC system including the wiring harness for proper connections, bent or broken pins, corrosion, loose wires, proper routing, etc. Check the Powertrain Control Module (PCM), sensors and actuators for physical damage. TPS, ICM, DISTRIBUTOR, etc. Check the engine coolant for proper level and mixture. Check the transmission fluid and engine oil level and quality. Make all necessary repairs before continuing with SELF TEST.

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 and; 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 and if possible, KOER.

A helper can assist you by counting the codes. Some use their smart phones to record them.

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.

One question, if Air Conditioning, if equipped and operational;
when Air Conditioning is in MAX mode does airflow switch to the windshield defroster hose nozzles with a small amount going to the heater outlet floor ducts?

Try unplugging the Idle Air Control (IAC)

Location pic by Steve
"First let me say this little thing has many names. But they all talk about the same item under the hood. Here all the names I've had the torture of learning throughout the years:
•Idle Air Bypass •Idle Air Control •Idle Speed Control •Throttle Bypass Air •Idle Bypass •Inlet Air Controller
•Inlet Air Bypass •Intake Air Bypass •Intake Air Control.
This is really easy to test. First as with all problems you should gather the trouble-codes from the computer. Follow the codes for testing and repair. If you get a code that points to a problem with the IAB start the vehicle and bring the engine up to operating temperature. Allow the engine to idle without any driver input to the throttle or pedal. Go under the hood, and disconnect the electrical connector to the IAB. If the engine begins to stubble or stalls the IAB is functional and does not need to be repaired. If the engine idle does not change you should remove the IAB for inspection.
The IAB can pass and still need repair, or it can fail and not need replacing. The plunger and internal spring can get clogged with dirt and oil. This will slow down the air flow and not allow the IAB to function properly. Remove the IAB and clean it. There are 2 halves to the IAB, and you can not buy just one half, but you can take it apart to clean it. But if the internal solenoid is faulty the IAB needs to be replaced." By Ryan M.
This is by Nelbur; "I have spent some time this week trying to set up an air bypass around the IAC valve by cutting away some of the gasket between the IAC in and out air holes, rather than pay big bucks for Fords spacer kit. I cut away the center of the original IAC gasket from the outside of each hole to the outside of the other hole, giving about 1/2" gap for the air to pass through. I noticed an immediate improvement in the engines starting behavior, but it would still die occasionally.

For most of my trucks life it has been dying when it was started hot. It would rev up and then drop the idle so low it would die unless I would catch the idle with the accelerator. It would never die when cold as the IAC would keep the idle speed up, and it never died at stop lights. Now it's worst situation seems to be when it has been shut down for a half hour or so, and restarted. I wonder if the heat soak is fooling the ETC into thinking the engine is warmer than it really is.
I decided that more improvement could be had if I had a thicker gasket, because the original IAC gasket was very thin (0.018"). I had some 0.030" gasket material so I made my own with the same 1/2" cut out. This gave enough bypass to noticeably raise the idle speed and almost eliminate the dying. After maybe 50 starts in the last few days, it only died twice. After so many years of catching it with the accelerator it is darned hard to leave my foot off it. It is clear to me that by trial and error one can tune the air bypass without the need for the expensive Ford kit. I may combine the two gaskets for more bypass, but the idle is about as fast as I would want now, especially for driving in snow."

Nelbur mentioned this Ford kit in..Idle Air Control (IAC) Sludge; Poor Idle TSB 91-25-07 for 85-92 Bronco & F Series & many others; "...Hard cold starts, hesitation and stalls on initial start-up or during idle or decel may be caused by sludge in the throttle body and/or idle by-pass valve. Sludge deposits or oil film on the throttle body bore and plate or the idle air by-pass valve may cause one or more of the following conditions. Hard Cold Start, Stall On Initial Start-Up, Stall During Idle, Stall During Decel, Rough Idle, Rolling Idle, Hesitation During Acceleration. A new idle air by-pass service kit (F2PZ-9F939-A) is now available for service use to correct sludge contamination concerns of the throttle bore and plate only. It eliminates the need to clean the majority of past model throttle body applications. Cleaning is not required on sludge tolerant throttle body designs released for 1991 and newer model years..."
Buy a Motorcraft IAC in event it needs to be replaced.

Aside from IAC, additional sensor inputs from the Engine Coolant sensor (ECT), brake switch and Throttle Position sensor are also used by the EEC IV to regulate idle speed according to various operating conditions.

Was the "throttle adjustment screw" assaulted by someone?

Throttle Position Sensor Testing, Replacement & Adjustment by Seattle FSB @ Throttle Position Sensor Testing, Replacement and Adjustment

Engine Coolant Temperature Sensor (ECT) Test:
Before you start blaming the engine coolant temperature sensor and replacing it make sure the rest of the coolant system is in good condition. All of the following items will affect the ECT:
*Coolant level *Radiator Fan *Water Pump *Water Pump and Fan Belts *Thermostat *Base Timing *Engines general condition *Harness and wire general condition
The Engine Coolant Temperature (ECT) sensor is a thermal transistor, which means it allows less electricity to pass through the sensor the warmer it gets. The ECT receives the Signal Retur voltage from the EEC, then allows a certain amount to return back to the EEC. Because the ECT is in direct contact with the engine coolant flow it changes resistance in response to the temperature of that coolant.

The ECT is third in command in the hierarchy of EFI sensors, this means this sensor is very important when calculating fuel ratios and timing curves. This is because of simply chemistry; fuel and spark are constants in the equation. Air is the biggest variable in combustion; it changes density greatly over a range of temperature. So keeping track of the changing temperatures of the incoming air and the engine in which it is burnt becomes very important. But due to its simplicity of design, the ECT is rarely at fault when problems occur.
Before testing the ECT or any other EFI component perform a self-test, trouble codes received during test can be used as a diagnostic tool along with other indicators. To test an ECT sensor you will need a volt meter. You can test the ECT by back probing the harness while reading the voltage returning to the EEC. Or you can removing the connector completely and test the resistance between the 2 pins on the ECT. The engine temperature must be greater than 50F (10C) to pass the KOEO Self-Test and greater than 180F (82C) to pass the KOER Self-Test. To accomplish this, the engine should be at normal operating temperature.

Engine Coolant
Temperature Sensor
FCVoltsK ohms
Values were calculated for VREF=5.0 volts. These values may vary 15 percent due to sensor and VREF variations." by Ryan M

Another ECT Sensor Test @ Checking resistance and voltage on the ECT sensor

ECT Sensor Location in a 96, same for your 92;

1 ECT Sensor Location (Part of 9424)
2 9F593 Fuel Injector
3 9C968 Fuel Pressure Regulator
4 9D280 Fuel Injection Supply Manifold
5 9D930 Fuel Charging Wiring
6 — Fuel Return Tube (Part of 9F792 Assembly)
7 — IAT Sensor Location (5.8L, 49 States Only)
(Part of 9424)
8 — Water Temperature Sender Location (Part of 9424)
9 — Pressure Relief Valve (Part of 9F792)

The engine coolant temperature sensor (ECT sensor) (12A648) changes resistance in response to changing temperature of the engine coolant. The engine coolant temperature sensor resistance decreases as the engine coolant temperature increases providing a signal to the powertrain control module (PCM) (12A650) indicating the temperature of the engine coolant.

Check for vacuum leaks see my test, post #11


Was speed control, if equipped recall work completed by dealership? Call local dealer or register and view status @ Welcome to Ford Owner | Official Ford Owner Site; or @ Recalls Look-up by VIN (Vehicle Identification Number) ... have VIN ready.
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.

Here is the 1995 Bronco Dealer Brochure

1995 Drivetrain, Powertrain Service Manual
1995 Bronco Drivetrain, Powertrain Service Manual - Google Drive

1995 Body, Chassis Service Manual
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

For any Bronco questions or to chat about it's planned modifications or build, it's better to post each seperately in Noobie Bronco Tech Questions. Flame free zone. This will get more attention and you can build up your post count to get into other sections such as Bronco and Ford Parts/Accessories (75 posts required to view).

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From the navigation, near the upper right-hand corner, click on your avatar and then select “Account Settings” from the drop down menu.

From your “Account Settings” page you will then see more navigation option of the left side. Select “Signature”.

Now you can simply enter your signature information in the text editor and click save.

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