Yo Tony,
Welcome!
[SIZE=14.4px]One way to check for exhaust leaks in engine bay:..seal up the tailpipe and introduce compressed air into the exhaust through the seal. Some use PVC pipe Caps. If 2 1/2"is too big, seal space with crunched aluminum foil, etc.[/SIZE]
[SIZE=14.4px]Drill a hole in end of cap so that a nozzle can fit in tightly.[/SIZE]
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Use a spray bottle filled with soapy water to see bubbles where the leak is located. Same as a plumber uses for gas pipe leaks.
A friend used muffler cement and tiger wrap on some leaks.
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Lack of Power:
Try a Self Test for Diagnostic Trouble Codes (DTC)s by my pal, BroncoJoe19
The engine temperature must be greater than 50° F for the Key On Engine Off (KOEO) Self-Test and if it can run long enough, greater than 180° F for the Key On Engine Running (KOER) Self-Test.
Run it around to heat the engine up if you can, 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
...
Some no code usual suspects by Ford;
Vacuum leak,
see my leak diagnosis link in post #11
Air filter, is it relatively clean?
Air inlet atop radiator support to filter box and to throttle body; look for obstruction; damaged tubing, openings in tubing, loose fit at throttle body or if equipped, at MAF sensor.
Fuel quality; Oxidized fuel often turns darker over time and may even smell sour. You can check stored gasoline by pouring some into a clear glass container and comparing it side-by-side with known fresh gasoline. If your old sample looks noticeably darker than the fresh gas, you have strong evidence the gas has gone bad.
Electrical connectors; inspect for corrosion, etc at coil, firewall, ICM, distributor, PCM, etc. especially those with broken locking tabs.
Transmission:
For 78 & 88, is C6 or AOD automatic shifting well?
Pull the transmission dipstick out when the engine is running at normal operating temp. The level should read FULL.
Look for leaks around pan from (front) Pump seal. Observe color and odor of the fluid. It should be red, not brown or black. Dark brown or black fluid that has distinct burnt odor, indicates a transmission in need of repair or overhaul.
Odor may indicate overheating condition, clutch disc or band failure. Use an absorbent white facial tissue and wipe the fluid level indicator. Examine the stain for evidence of solid particles and for engine coolant signs (gum or varnish on fluid level indicator).
If particles are present in the fluid or there is evidence of engine coolant or water, the transmission pan must be removed for further inspection.
Is AOD downshifting well?
°°°
Sixlitre Tune-Up @
Sewiv's ignition upgrade and timing bump;
°°°
"Make sure you have VERY good plug wires though. Ford's racing wires are competatively priced.
Remember to get the cheapest Autolites or Motorcraft plugs you're money will buy, as anything better is wasted on small block Fords.
As far as the cap & rotor they're all good, as long as they're as good as new with no arc'ing on the inner terminals and no cracks in the plastic."
More;
Reduce weight of the Bronco and tools, accessories and ... passengers; driver's get a pass
; also, grille guards, side steps, etc.
Ensure that brakes are not dragging
Proper tire pressure, under inflated tires Increase rolling resistance
Dirty air filter causes excessively rich fuel/air mixture
Worn spark plugs cause inefficient combustion, wasted fuel
"Leaking" plug wires due to deteriorated insulation
Don't over-oil a K&N filter!
Inspect exhaust system for blockage, damage.
& more Items that Cost $:
COLD air intake - insulate air intake from grille entry area to throttle body.
Air Tube & Box Insulation pics in a 94 5.0; Ken used Reflectix Insulation, avail @ Lowes. etc. ST16025 - 16" x 25 feet. miesk5 Note; Ken installed the K&N® & removed the cold air intake tube that runs to the top of the radiator; but he could have installed the intake tube section later.
Source: by Ken B (Kenny's 94)
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High Quality Motorcraft TFI Ignition Coil Attributes
Source: by SeattleFSB (Seattle FSB) @ MSD 8227 coil problems
Many Bronco owners shop for an ignition coil by looking for the highest voltage available. But I venture to say that there is much more to look for in achieving both a quality ignition system and saving money in the long run.
For clarification, it takes approximately 10-14,000 volts to initiate the spark across the OEM spark plug gap. After the initial arc, the voltage required to sustain the arc is much less and drops off significantly. So while you may have a 48,000v coil you can't actually get that across the plug. The extra power becomes reserve voltage which compensates for worn plugs, increasing resistance in wires and carbon fouling. This increased stress can require an additional 1-5000 volts.
Fact is a higher voltage coil does not work any better, it just lasts longer due to having a higher reserve reducing heat. You cannot push more than 20,000 volts across a spark plug without bad things happening. If you were to try you would see arcing down the side of the plug, across carbon buildups at the electrode end and out any weak points in the wire insulation and connections.
The bottom line is the ideal coil output required for normal applications is about 30,000 volts. So no, your coil does not need to be 48,000v for proper ignition. The benefit would be in having enough reserve to compensate for high resistance due to a worn or altered ignition system.
This is why the Sixlitre Tune recommends a 48,000v coil and larger spark plug wires – to compensate for a substantial increase in resistance from larger than specified spark plug gaps. You are adding resistance as the spark attempts to reach ground. This in turn causes the plug wires to break down and decreases the service life of the rotor, distributor cap, spark plugs and increases the chance of spark scatter within the Distributor Cap.
Think about it, you are setting your spark plugs at a maximum gap even before wear. The higher voltage coil does not reduce stress and wear on your ignition system; it only compensates within a larger margin and then ultimately becomes dependent upon the quality of construction for survival. When opening up your spark plug gap from factory specifications you must be prepared to check your secondary ignition system annually, as opposed to about 40,000 miles with a stock vehicle, or risk performance decreases down the road.
With that being said, IMHO the Motorcraft DG470 TFI Coil is one of the most dependable 48,000v TFI Coils on the market. This is largely due to the quality in design, testing and construction. I have personally had many dependability issues with other imported TFI Coils, such as MSD. Where a Motorcraft Coil has lasted 15 years, I have went through three MSD coils in five years. Your purchase of a TFI Coil should not be totally dependent upon the voltage, but strong consideration."
EFI Performance Upgrades by Ryan M
How to pick a CAMSHAFT for EFI by Ryan M (formerly @Fireguy50
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Here is the
1988 Bronco Dealer Brochure
For your 88, look at Some Wiring Diagrams & Technical Service Bulletins @
http://www.bbbind.com/tsb-wiring-diagrams-database/
For the 78 it will just show some Technical Service Bulletins.
1978 Bronco Dealer Brochure via Indybronco
1978 Bronco Emission Component Location Diagrams via 78brncoxlt
1978 Ford Bronco & Truck Wiring Diagrams by Ford via Bronc Mom @
https://drive.google.com/file/d/15KE...ftmGiO7fN/view
1979 Bronco/F Series Electrical & Vacuum Troubleshooting Manual via topsig (Ziggy); similar to 78.
1979 Wiring Schematics, Connector Pin-outs, etc by Ranger429 @
https://www.fullsizebronco.com/forum...chematics.html
Similar to 78
Bubba's M-Block Ford V8 Workshop by Dave Resch @
Bubba's M-Block Ford V8 Workshop
MANY 78 Parts Break-Out Diagrams by Indybronco (Lula Mae) @
pictures, videos, and sounds | SuperMotors.net
78 351M/400 Engine Exhaust Emission Control Information Decal & Timing by member grovermyson @
https://www.fullsizebronco.com/forum...-anything.html
C6 Auto Transmission, if equipped, Description & Operation, Adjustments, Diagnosis & Testing (partial), Disassembly & Assembly, Parts Break-Out Diagram, Hydraulic Control System Diagram, Removal & Installation & Specifications @
https://redirect.viglink.com/?format...eak-Out%20Diag...
Partial Chilton Manual for 1978, 1979, 1980, 1981 Bronco. Scanned by broncocity.com @
https://web.archive.org/web/20130419...6-81manual.htm
Ford Shop Manual Diagrams: 1978-1979 Full Size Shop Manuals, partial @
https://broncograveyard.com/rt-1273-...-archives.html
My Tablet takes too long to download, so try the first in this list as long as you have Adobe Acrobat 9 installed. Let me know if the downloads are worth the effort.
Includes:
Wiring Manuals & Diagrams Download PDF
This complete manual for the 1972-1979 Ford Bronco Includes Rear Lights Diagram
Motor Manuals & Diagrams Download PDF
This complete manual for the 1972-1979 Ford Bronco Includes Air Cleaner Diagram
Chassis Manuals & Diagrams Download PDF
This complete manual for the 1972-1979 Ford Bronco Includes '78 Brakes Diagram, Gas Tank Setup Diagram
Body Manuals & Diagrams Download PDF This complete manual for the 1972-1979 Ford Bronco Includes; Upper Body Diagram, Front Clip Diagram, heater Ducts Diagram, Tailgate Diagram, Console Diagram, Front Clip Diagram, Grill Setup Diagram, Heater Controls Diagram, Interior Trip Diagram, Rear Sheetmetal Diagram, Tilt wheel Diagram, Tire Rack.
GL!
Al
