Bronco just wont start?
- Thread starter robofg
- Start date
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yo R,
This looks a lot to do, but is what a Ford seervice tech would go through and charge $$$
No Start, but Cranks and or Misfire, etc.; Thick Film Ignition (TFI) Testing, Overview & Diagrams; "...This article applies to both the Gray colored Ignition Control Module and the Black colored Ignition Control Module. The Gray colored Ignition Control Module is called the Push Start Module and the Black colored Ignition Control Module is called the Computer Controlled Dwell Module. Part I; In This Fast Test you'll be able to pinpoint the problem to the Ignition Control Module or the Ignition Coil or the Profile Ignition Pickup Sensor (PIP Sensor) in four easy test steps. This test will only help you in a Cranks but Does Not Start Condition.
http://easyautodiagnostics.com/ford_ignition_module/distributor_mounted_module_1.php
You'll need to get some things such as an LED @ Radio Shack or from spare parts and a multimeter
For Spark Tester, DIY; W/ an old spark plug and cut off the L-shaped tip
====
Also consider this Ignition Control Module Relocation & Modified Mount in a 90
Source: by Seattle FSB (SeattleFSB) at http://www.supermotors.net/registry/20487/75165
more LINKs for this in my site @ http://www.broncolinks.com/index.php?index=230
This looks a lot to do, but is what a Ford seervice tech would go through and charge $$$
No Start, but Cranks and or Misfire, etc.; Thick Film Ignition (TFI) Testing, Overview & Diagrams; "...This article applies to both the Gray colored Ignition Control Module and the Black colored Ignition Control Module. The Gray colored Ignition Control Module is called the Push Start Module and the Black colored Ignition Control Module is called the Computer Controlled Dwell Module. Part I; In This Fast Test you'll be able to pinpoint the problem to the Ignition Control Module or the Ignition Coil or the Profile Ignition Pickup Sensor (PIP Sensor) in four easy test steps. This test will only help you in a Cranks but Does Not Start Condition.
http://easyautodiagnostics.com/ford_ignition_module/distributor_mounted_module_1.php
You'll need to get some things such as an LED @ Radio Shack or from spare parts and a multimeter
For Spark Tester, DIY; W/ an old spark plug and cut off the L-shaped tip
====
Also consider this Ignition Control Module Relocation & Modified Mount in a 90
Source: by Seattle FSB (SeattleFSB) at http://www.supermotors.net/registry/20487/75165
more LINKs for this in my site @ http://www.broncolinks.com/index.php?index=230
Rons beast
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Hey Robofg,
I'm assuming the engine is FI. Can you give us some more details? How did you "purposely flood it"?
If the engine is flooded it will be very hard to start as long as the plugs are wet.
If the engine has been sitting for awhile so the plugs can dry, you can try to crank the engine while the accelerator is wide open, ( To the floor). This puts the comp in an "emergency start mode" so to speak.
All the sensor inputs are ignored and it goes back to basic pre programed actions..... ( air+fuel+compression+spark=boom).
If that still doesn't result in a start, go back and check the basics again. Sometimes when frustration creeps in we tend to overlook things.
Report back here and we can maybe of more help.
Good Luck
I'm assuming the engine is FI. Can you give us some more details? How did you "purposely flood it"?
If the engine is flooded it will be very hard to start as long as the plugs are wet.
If the engine has been sitting for awhile so the plugs can dry, you can try to crank the engine while the accelerator is wide open, ( To the floor). This puts the comp in an "emergency start mode" so to speak.
All the sensor inputs are ignored and it goes back to basic pre programed actions..... ( air+fuel+compression+spark=boom).
If that still doesn't result in a start, go back and check the basics again. Sometimes when frustration creeps in we tend to overlook things.
Report back here and we can maybe of more help.
Good Luck
Rons Beast.
I have changed the ignition module,coil and fuel filter. Yesterday after i changed coil it acted like it wanted to start then all it did was just turn and turn, it never fired. same today after i changed fuel filter, at first it acted like it might start then it did nothing but crank over? Timing maybe??
Thanks again for any ideas guys. Yes and motor is FI.
I have changed the ignition module,coil and fuel filter. Yesterday after i changed coil it acted like it wanted to start then all it did was just turn and turn, it never fired. same today after i changed fuel filter, at first it acted like it might start then it did nothing but crank over? Timing maybe??
Thanks again for any ideas guys. Yes and motor is FI.
Krafty
New member
This is were very good diagnostics can save you alot of time, money and headaches. If you have good spark then why did you change the coil? what was the engine doing that prompted you to change the ICM? Have you checked for fuel pressure?
Now ill get to the worst case scenarios, scenario 1= you have good spark, good fuel pressure, set Top Dead Center on piston 1 and check the timing marks, and distributor rotor. in this situation the timing chain has jumped causing your ignition timing to be off. reset the distributor cap so the rotor is pointing as the terminal for the #1 cylinder. this is not a fix but it will get you moving again.
scenario 2= you have good spark, fuel pressure is good, you've checked your timing and it all looks good. the ECM or PCM has malfunctioned because of a faulty input from a sensor ( MAP, or Engine Coolant Temp sensor) causing it not to fire the injectors at the right time or for the right length of time.
Or the PCM has a fault and needs to be replaced by one from a donor vehicle with the same drivetrain combo as your bronco.
good luck
Now ill get to the worst case scenarios, scenario 1= you have good spark, good fuel pressure, set Top Dead Center on piston 1 and check the timing marks, and distributor rotor. in this situation the timing chain has jumped causing your ignition timing to be off. reset the distributor cap so the rotor is pointing as the terminal for the #1 cylinder. this is not a fix but it will get you moving again.
scenario 2= you have good spark, fuel pressure is good, you've checked your timing and it all looks good. the ECM or PCM has malfunctioned because of a faulty input from a sensor ( MAP, or Engine Coolant Temp sensor) causing it not to fire the injectors at the right time or for the right length of time.
Or the PCM has a fault and needs to be replaced by one from a donor vehicle with the same drivetrain combo as your bronco.
good luck
yo robofg,
No Start Troubleshooting but Starter Cranks Engine in 4.9, 5.0, or 5.8L; "....TIP 1: Since a lot of folks confuse a No Crank Condition with a No Start Condition. I'll clear it up right now: In a No Start Condition means your vehicle's Starter Motor is cranking the Engine but the Engine is not starting. In a No Crank Condition, the Engine is not cranking when you turn the key to crank the Engine. This article only deals with a No Start Condition..." read more Source: by easyautodiagnostics
Here are the contents of this article at a quick glance:
•Important Tips and Suggestions.
•No Start Condition Basics
•No Start 1: Checking for Spark.
•No Start 2: Checking for Fuel.
•No Start 3: Checking Engine Mechanical Condition.
•No Start Summary.
•Related Test Articles
No Start Troubleshooting but Starter Cranks Engine in 4.9, 5.0, or 5.8L; "....TIP 1: Since a lot of folks confuse a No Crank Condition with a No Start Condition. I'll clear it up right now: In a No Start Condition means your vehicle's Starter Motor is cranking the Engine but the Engine is not starting. In a No Crank Condition, the Engine is not cranking when you turn the key to crank the Engine. This article only deals with a No Start Condition..." read more Source: by easyautodiagnostics
Here are the contents of this article at a quick glance:
•Important Tips and Suggestions.
•No Start Condition Basics
•No Start 1: Checking for Spark.
•No Start 2: Checking for Fuel.
•No Start 3: Checking Engine Mechanical Condition.
•No Start Summary.
•Related Test Articles
Krafty,
At the begining of my problems the bronco was very stubborn to start, it took many cranks until it started, it just got worse, now it just turns over and doesent start.
Changed plugs and wires this wkend 11/17/12 and it acts like it wants to start but still wont fire. how would you recomend checking for fuel pressure.
Thanks again.
At the begining of my problems the bronco was very stubborn to start, it took many cranks until it started, it just got worse, now it just turns over and doesent start.
Changed plugs and wires this wkend 11/17/12 and it acts like it wants to start but still wont fire. how would you recomend checking for fuel pressure.
Thanks again.
Krafty
New member
on the fuel rail on the drivers side there should be a valve that looks like a tire valve. you can buy or borrow a fuel pressure gauge that threads onto that valve, when you try to start it it will read the fuel pressure in the rail, 35+ psi = good fuel pressure.
Krafty,
So have good fuel pressure and spark. Ive replaced all wires and plugs, Ignition control module, coil and fuel filter.timing is is correct. turns over great but still will not start? any other ideas?
Thanks again. Robert G.
So have good fuel pressure and spark. Ive replaced all wires and plugs, Ignition control module, coil and fuel filter.timing is is correct. turns over great but still will not start? any other ideas?
Thanks again. Robert G.
Krafty
New member
sounds like a faulty pcm thats not telling your injectors to pulse. try to find one out of a wrecker to keep cots down, but remember the donor f150 or bronco has to have the same engine and transmission combo as yours otherwise it wont work properly.
yo
in the article I posted above; No Start Troubleshooting but Starter Cranks Engine in 4.9, 5.0, or 5.8L; "....TIP 1: Since a lot of folks confuse a No Crank Condition with a No Start Condition. I'll clear it up right now: In a No Start Condition means your vehicle's Starter Motor is cranking the Engine but the Engine is not starting. In a No Crank Condition, the Engine is not cranking when you turn the key to crank the Engine. This article only deals with a No Start Condition..." read more
excerpts;
Checking for Fuel involves two separate tests. One is to check that the Fuel Pump is functioning and supplying the correct amount of pressure.
This is by Ryan M; "After attaching the fuel pressure tester, run the fuel pump for 10 seconds. Check that the pressure is within specs, and it doesn’t leakdown more than 5PSI within 60 seconds after pump shutdown."
The other test is making sure that the PCM is activating the Fuel Injectors. This can easily be accomplished by using a Noid Light to check for these On/Off activation pulses the PCM sends to the Injectors.
How to Test the Fuel Injectors(5.0L Engine, 5.8L Engine
On a relatively "quiet engine" (no extreme noises from exh leaks, glass packs, etc.) I use a very long thim ***** driver etc. to listen to each injector click
and
One of the most overlooked areas, when testing a hard to diagnose No Start, is the mechanical condition of your 4.9L, 5.0L or 5.8L Ford car, pick up, van or SUV.
Checking the Engine mechanical condition means an engine compression test.
•When performing an Engine Compression Test, what you're looking for is an average compression reading of less than 90 PSI across all or the majority of the Engine Cylinders.
•If you have one or just two readings that are under 90 PSI your Ford vehicle will still start and run, albeit with a Misfire Condition.
•I've written a How to do a Compression Test article that you may find useful. Although this article is geared towards finding a hard to diagnose Misfire (and written for the 4.6L and 5.4L Engines), if you have never done a Compression Test... this article will help you 4.6L, 5.4L Engine Compression Test.
in the article I posted above; No Start Troubleshooting but Starter Cranks Engine in 4.9, 5.0, or 5.8L; "....TIP 1: Since a lot of folks confuse a No Crank Condition with a No Start Condition. I'll clear it up right now: In a No Start Condition means your vehicle's Starter Motor is cranking the Engine but the Engine is not starting. In a No Crank Condition, the Engine is not cranking when you turn the key to crank the Engine. This article only deals with a No Start Condition..." read more
excerpts;
Checking for Fuel involves two separate tests. One is to check that the Fuel Pump is functioning and supplying the correct amount of pressure.
This is by Ryan M; "After attaching the fuel pressure tester, run the fuel pump for 10 seconds. Check that the pressure is within specs, and it doesn’t leakdown more than 5PSI within 60 seconds after pump shutdown."
The other test is making sure that the PCM is activating the Fuel Injectors. This can easily be accomplished by using a Noid Light to check for these On/Off activation pulses the PCM sends to the Injectors.
How to Test the Fuel Injectors(5.0L Engine, 5.8L Engine
On a relatively "quiet engine" (no extreme noises from exh leaks, glass packs, etc.) I use a very long thim ***** driver etc. to listen to each injector click
and
One of the most overlooked areas, when testing a hard to diagnose No Start, is the mechanical condition of your 4.9L, 5.0L or 5.8L Ford car, pick up, van or SUV.
Checking the Engine mechanical condition means an engine compression test.
•When performing an Engine Compression Test, what you're looking for is an average compression reading of less than 90 PSI across all or the majority of the Engine Cylinders.
•If you have one or just two readings that are under 90 PSI your Ford vehicle will still start and run, albeit with a Misfire Condition.
•I've written a How to do a Compression Test article that you may find useful. Although this article is geared towards finding a hard to diagnose Misfire (and written for the 4.6L and 5.4L Engines), if you have never done a Compression Test... this article will help you 4.6L, 5.4L Engine Compression Test.
Rons beast
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Hey Robo,
The codes relate as follows:
24 = Intake air charge temperature sensor or vane out of range.
26 = Trans oil tempsensor fault
67 = Ac compressor clutch switch fault
These codes are for trucks. The #26 and #67 codes are for something different when related to cars.
These codes are for 1985- 1990 Bronco..5.0 FI with 8th vin digit= N.
Other than IACT sensor I can't think that the others would cause a no start.
Does your engine have a IACT sensor? It would be in the intake mainfold on the right side of the engine. Looks like a water temp sensor. ( check the pic)
Let us know
Good Luck
The codes relate as follows:
24 = Intake air charge temperature sensor or vane out of range.
26 = Trans oil tempsensor fault
67 = Ac compressor clutch switch fault
These codes are for trucks. The #26 and #67 codes are for something different when related to cars.
These codes are for 1985- 1990 Bronco..5.0 FI with 8th vin digit= N.
Other than IACT sensor I can't think that the others would cause a no start.
Does your engine have a IACT sensor? It would be in the intake mainfold on the right side of the engine. Looks like a water temp sensor. ( check the pic)
Let us know
Good Luck
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