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Registered
1995 Ford Bronco Eddie Bauer 5.8 lt.
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58 Posts
Discussion Starter · #1 ·
My truck is pinging when I accelerate, I changed the gas octane to premium, added octane booster and even added Techron to clean the injection system. Still pinging, I have not read the spark plugs but that is in the bucket list, I need do to a full tune up . Any other suggestions?
I did notice that the idle seems too high; 1100 rpms vs 750-800.
 

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The Tennessee Warden
96 XL, built 357W, E4OD, BW1356, 4.56 gears
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5,094 Posts
First thing you should do is a little reading up on what exactly detonation (or spark knock) is and how it happens.

I am a bit surprised that premium gas didn’t help, as it is more resistant to combustion and usually lessens occurrence of detonation. Your combustion chamber may have excessive carbon deposits in it. A tune up should help - new plugs, wires, coil, dizzy cap and rotor - maybe a Seafoam treatment too. Check your ignition timing too - set to 10° BTDC with the spout removed.
 

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Registered
1995 Ford Bronco Eddie Bauer 5.8 lt.
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58 Posts
Discussion Starter · #3 ·
First thing you should do is a little reading up on what exactly detonation (or spark knock) is and how it happens.

I am a bit surprised that premium gas didn’t help, as it is more resistant to combustion and usually lessens occurrence of detonation. Your combustion chamber may have excessive carbon deposits in it. A tune up should help - new plugs, wires, coil, dizzy cap and rotor - maybe a Seafoam treatment too. Check your ignition timing too - set to 10° BTDC with the spout removed.
All these things are in q to get it done, weather permitting up here in the Northeast. Have a wonderful Thanksgiving and thanks for the input.
Lou
 

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240 Posts
Can you tell if it's occuring in the top or the bottom of the engine?
When you say it happens under acceleration, is it any acceleration at any speed or only from a standstill or only under hard acceleration?
 

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Premium Member
1982 Bronco XLT Lariat, 351W, C6; 1989 Bronco XLT, 302, AOD
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245 Posts
From your normal driving speed kick it down in passing gear and hold it there until it shifts out on it's own. Maybe do this a couple of times. If it is carbon build-up in the combustion chambers this should clear it out. Won't hurt your engine!
TB
 
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Super Moderator
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29,427 Posts
Yo Basque1
KNOCK / PING Perpetrators
Fuel Quality as MS88Bronc advised
Vacuum Leak
Engine Overheating
Base Timing as MS88Bronc advised.

See my Vacuum leak test in post #11 incl jowens126 HVAC Control Panel info & Mikey350 HIGH IDLE tests @ Help with dtc codes and idle
Tip:
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.


FUEL - VOLATILITY RELATED DRIVEABILITY INFORMATION
Article No.
96-5-4
02/26/96
FUEL - INFORMATION ON GASOLINE - TIPS TO
RESOLVE VOLATILITY RELATED DRIVEABILITY
CONCERNS
FORD:
1992-93 FESTIVA
1992-94 TEMPO
1992-96 CROWN VICTORIA, ESCORT, MUSTANG, PROBE, TAURUS, THUNDERBIRD
1994-96 ASPIRE
1995-96 CONTOUR

LINCOLN-MERCURY:
1992-94 CAPRI, TOPAZ
1992-96 CONTINENTAL, COUGAR, GRAND MARQUIS, SABLE, TOWN CAR, TRACER
1993-96 MARK VIII
1995-96 MYSTIQUE

LIGHT TRUCK:
1992-96 AEROSTAR, BRONCO, ECONOLINE, EXPLORER, F-150-350 SERIES, F-47, RANGER
1993-96 VILLAGER
1995-96 WINDSTAR

MEDIUM/HEAVY TRUCK:
1992-96 F-700

This TSB article is being republished in its entirety to include 1995-96 model year vehicles.

ISSUE:
Additional information on gasoline tips to resolve volatility related driveability concerns have been developed.

ACTION:
Refer to the following text for further information.

WARM ENGINE/WARM-HOT AMBIENT TEMPERATURE DRIVEABILITY CONCERN

Unleaded gasoline with volatility too HIGH for ambient temperatures cause hot-start/warmed-up driveability concerns such as no start, rough idle, surging and other "vapor lock" related concerns during warmed-up driving and hot engine restarts.

COLD ENGINE/COOL AMBIENT TEMPERATURE DRIVEABILITY CONCERN

Unleaded gasoline with volatility too LOW for ambient temperatures cause cold-start/warm-up driveability concerns such as long crank times, rough idle, hesitation, poor throttle response, induction backfire, stalls and similar symptoms caused by lean operation during initial cold start and driveaway.

Gasoline distribution practices often do not allow branded marketers to have much control over their gasoline's volatility other than Reid Vapor Pressure (RVP). Oxygenate (e.g., ethanol, methyl tertiary butyl ether (MTBE)) use is more dependent on local gasoline markets, rather than specific marketers practice. Therefore, it is difficult to recommend specific brands to avoid volatility related complaints.

Gasolines are seasonally adjusted, meaning they have higher volatility (vaporize easier) in the winter and lower volatility in the summer. Recent government mandates to improve air quality have caused significant changes to gasolines, such as the mandatory use of oxygenates (ethanol, MTBE and others), in the winter or the reduction of RVP in the summer. The addition of oxygenates (especially ethanol) increases volatility while the reduction of RVP reduces volatility.

RVP is one measure of volatility, and probably the most familiar, but RVP alone does not sufficiently characterize the volatility of the gasoline. As a gasoline is a complex blend of hydrocarbon (and oxygenate) liquids, it has a boiling range rather than a single boiling temperature (like water). The concerns are largely caused by the characteristics of this boiling range, called the distillation curve.

Unfortunately, fuel vapor pressure measured with the Rotunda Gas Check 014-00335, and similar tools, does not sufficiently analyze the gasoline distillation curve. The gas check tool may be used to determine alcohol and water content, although a gasoline that tests satisfactorily with these tools may still cause driveability concerns due to the distillation curve which cannot be measured by these tools. Currently, no service tools are available to measure the distillation curve.

Often no trouble codes will be found. If the subject concerns are not corrected through engine/emission diagnostic routines, the concerns may be caused by the gasoline. The following tips may help further diagnose these concerns.

WARM ENGINE/WARM-HOT AMBIENT TEMPERATURE DRIVEABILITY CONCERNS

Typically experienced during periods of unseasonably warm weather during the spring or early summer when winter gasolines are still available.

Through experience, try to identify a reliable source for fresh, good quality gasoline such as a station that receives frequent shipments. Using such gasoline should be more appropriate for ambient conditions and should resolve the concern.

No fuel tank additives will resolve these concerns.

COLD ENGINE/COOL AMBIENT TEMPERATURE DRIVEABILITY CONCERNS

Some Premium Octane Grade gasolines (91 (R+M)O/2 or higher) in the past have caused this concern, however during the past two summers these concerns have also been caused by some Regular Octane Grade gasolines. As RVP was lowered (summer 1992) to meet EPA mandates, the distillation characteristics of the gasoline that influence cold start/warm-up performance were not adjusted to compensate for the lower RVP. These characteristics were allowed to become similar to the premium gasolines that had caused concerns in the past.

^ Advise customers using a higher octane grade than recommended in their Owner's Guide to switch to the recommended grade (for most vehicles regular octane grade unleaded gasoline 87 (R+M)/2).

^ DO NOT advise using a higher octane grade unleaded gasoline than is recommended for that specific engine. Premium octane grade unleaded gasolines do not provide better fuel economy or performance than regular octane gasolines. Only advise using higher octane grade unleaded gasoline to avoid potentially damaging spark knock or ping, but do so ONLY after diagnostic procedures have been ineffective.

^ Advise customers using the recommended octane grade unleaded gasoline to try another brand.

^ Advise customers using a gasoline containing an oxygenate to try another type of oxygenated gasoline, or if available, a gasoline that does not contain an oxygenate. The oxygenate type, and perhaps the amount, should be posted on the pumps.

^ No fuel tank additives will resolve these concerns.

NOTE:
ALWAYS USE AN UNLEADED GASOLINE WITH AN "INTAKE SYSTEM DEPOSIT CONTROL" DETERGENT THAT HELPS MAINTAIN PROPER OPERATION OF YOUR VEHICLE'S FUEL INJECTORS, AS WELL AS KEEPING THE VALVES CLEAN.

NOTE:
●THESE TIPS MAY BE USED ON ANY MODEL YEAR VEHICLE EXHIBITING THESE CONCERNS.

OTHER APPLICABLE ARTICLES: 91-8-13

SUPERSEDES: 94-12-3

WARRANTY STATUS: INFORMATION ONLY

OASIS CODES: 40200, 404000, 602300, 603300, 607000, 607400, 608000, 608400, 609000, 609400, 610000, 611000, 611500, 612000, 614000, 614500, 623000
RELATED INFORMATION
 

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Registered
Joined
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219 Posts
I did a full tune up on my 92 5L a few years back when I still owned it. Complete with new plug wires and ended up with a ping. I remember someone on here mentioning the location of the wires in the looms( I think it was on the passenger side). I repositioned the wires and the ping went away.
 

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Driving Stuff Henry Built
-90 xlt, 351w, e4od, man 1356, 3.55, sag, warn hubs, 35s. -73, 400, np435, d20j twin, 35s
Joined
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9,042 Posts
Pinging & high idle could both be symptoms of a vacuum leak. Since you have both I'd probably start looking there.

Pinging occurs when the air fuel mixture in the cylinder lights off too early. The sound you hear is the explosion that should be pushing your piston down being compressed until the piston reaches the top of its travel. That's a bad thing.

There can be some different causes. Here's what comes to mind right off:

Timing that is too far advanced causing the spark plug to fire too early. It's always a good idea to check your timing when looking for a ping.

Or it can be ignited too early on its own, with no spark yet, by factors happening inside the cylinder.
-Too hot. As the mixture is compressed the heat in the cylinder causes it to explode on its own. This is basically how a diesel engine works. On a gas vehicle you look for overheating of the cooling system.
-A hot spot in the engine. Points of carbon build up can hold heat & light it off. That's where the info above is trying to get you to blow out the carbon.
-The air/fuel mixture is too lean. When it's too lean it can light off on its own. That's where a vacuum leak comes into play, because it makes it run lean. Too little fuel being delivered can also cause the same situation.
-Too low of octane for the compression ratio of the engine. If the compression is higher, low octane gas will explode as it's being compressed too much for its rating. But if it used to run ok on lower octane fuel, but recently started pinging, that's probably not the issue. Since you increased the octane eith no change, I'd look elsewhere.
-Carbon build up reducing combustion chamber volume can also be a factor. It increases the compression ratio by filling up space.
-Misfiring on the wrong cylinder. As Bogie mentioned crossfiring with wires routed improperly can come into play. Or the firing order crossed up.

In my personal experience the common causes for pinging are vacuum leaks, restricted fuel, & overheating. More so than carbon build up.
 

·
Registered
1995 Ford Bronco Eddie Bauer 5.8 lt.
Joined
·
58 Posts
Discussion Starter · #10 ·
Yo Basque1
KNOCK / PING Perpetrators
Fuel Quality as MS88Bronc advised
Vacuum Leak
Engine Overheating
Base Timing as MS88Bronc advised.

See my Vacuum leak test in post #11 incl jowens126 HVAC Control Panel info & Mikey350 HIGH IDLE tests @ Help with dtc codes and idle
Tip:
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.


FUEL - VOLATILITY RELATED DRIVEABILITY INFORMATION
Article No.
96-5-4
02/26/96
FUEL - INFORMATION ON GASOLINE - TIPS TO
RESOLVE VOLATILITY RELATED DRIVEABILITY
CONCERNS
FORD:
1992-93 FESTIVA
1992-94 TEMPO
1992-96 CROWN VICTORIA, ESCORT, MUSTANG, PROBE, TAURUS, THUNDERBIRD
1994-96 ASPIRE
1995-96 CONTOUR

LINCOLN-MERCURY:
1992-94 CAPRI, TOPAZ
1992-96 CONTINENTAL, COUGAR, GRAND MARQUIS, SABLE, TOWN CAR, TRACER
1993-96 MARK VIII
1995-96 MYSTIQUE

LIGHT TRUCK:
1992-96 AEROSTAR, BRONCO, ECONOLINE, EXPLORER, F-150-350 SERIES, F-47, RANGER
1993-96 VILLAGER
1995-96 WINDSTAR

MEDIUM/HEAVY TRUCK:
1992-96 F-700

This TSB article is being republished in its entirety to include 1995-96 model year vehicles.

ISSUE:
Additional information on gasoline tips to resolve volatility related driveability concerns have been developed.

ACTION:
Refer to the following text for further information.

WARM ENGINE/WARM-HOT AMBIENT TEMPERATURE DRIVEABILITY CONCERN

Unleaded gasoline with volatility too HIGH for ambient temperatures cause hot-start/warmed-up driveability concerns such as no start, rough idle, surging and other "vapor lock" related concerns during warmed-up driving and hot engine restarts.

COLD ENGINE/COOL AMBIENT TEMPERATURE DRIVEABILITY CONCERN

Unleaded gasoline with volatility too LOW for ambient temperatures cause cold-start/warm-up driveability concerns such as long crank times, rough idle, hesitation, poor throttle response, induction backfire, stalls and similar symptoms caused by lean operation during initial cold start and driveaway.

Gasoline distribution practices often do not allow branded marketers to have much control over their gasoline's volatility other than Reid Vapor Pressure (RVP). Oxygenate (e.g., ethanol, methyl tertiary butyl ether (MTBE)) use is more dependent on local gasoline markets, rather than specific marketers practice. Therefore, it is difficult to recommend specific brands to avoid volatility related complaints.

Gasolines are seasonally adjusted, meaning they have higher volatility (vaporize easier) in the winter and lower volatility in the summer. Recent government mandates to improve air quality have caused significant changes to gasolines, such as the mandatory use of oxygenates (ethanol, MTBE and others), in the winter or the reduction of RVP in the summer. The addition of oxygenates (especially ethanol) increases volatility while the reduction of RVP reduces volatility.

RVP is one measure of volatility, and probably the most familiar, but RVP alone does not sufficiently characterize the volatility of the gasoline. As a gasoline is a complex blend of hydrocarbon (and oxygenate) liquids, it has a boiling range rather than a single boiling temperature (like water). The concerns are largely caused by the characteristics of this boiling range, called the distillation curve.

Unfortunately, fuel vapor pressure measured with the Rotunda Gas Check 014-00335, and similar tools, does not sufficiently analyze the gasoline distillation curve. The gas check tool may be used to determine alcohol and water content, although a gasoline that tests satisfactorily with these tools may still cause driveability concerns due to the distillation curve which cannot be measured by these tools. Currently, no service tools are available to measure the distillation curve.

Often no trouble codes will be found. If the subject concerns are not corrected through engine/emission diagnostic routines, the concerns may be caused by the gasoline. The following tips may help further diagnose these concerns.

WARM ENGINE/WARM-HOT AMBIENT TEMPERATURE DRIVEABILITY CONCERNS

Typically experienced during periods of unseasonably warm weather during the spring or early summer when winter gasolines are still available.

Through experience, try to identify a reliable source for fresh, good quality gasoline such as a station that receives frequent shipments. Using such gasoline should be more appropriate for ambient conditions and should resolve the concern.

No fuel tank additives will resolve these concerns.

COLD ENGINE/COOL AMBIENT TEMPERATURE DRIVEABILITY CONCERNS

Some Premium Octane Grade gasolines (91 (R+M)O/2 or higher) in the past have caused this concern, however during the past two summers these concerns have also been caused by some Regular Octane Grade gasolines. As RVP was lowered (summer 1992) to meet EPA mandates, the distillation characteristics of the gasoline that influence cold start/warm-up performance were not adjusted to compensate for the lower RVP. These characteristics were allowed to become similar to the premium gasolines that had caused concerns in the past.

^ Advise customers using a higher octane grade than recommended in their Owner's Guide to switch to the recommended grade (for most vehicles regular octane grade unleaded gasoline 87 (R+M)/2).

^ DO NOT advise using a higher octane grade unleaded gasoline than is recommended for that specific engine. Premium octane grade unleaded gasolines do not provide better fuel economy or performance than regular octane gasolines. Only advise using higher octane grade unleaded gasoline to avoid potentially damaging spark knock or ping, but do so ONLY after diagnostic procedures have been ineffective.

^ Advise customers using the recommended octane grade unleaded gasoline to try another brand.

^ Advise customers using a gasoline containing an oxygenate to try another type of oxygenated gasoline, or if available, a gasoline that does not contain an oxygenate. The oxygenate type, and perhaps the amount, should be posted on the pumps.

^ No fuel tank additives will resolve these concerns.

NOTE:
ALWAYS USE AN UNLEADED GASOLINE WITH AN "INTAKE SYSTEM DEPOSIT CONTROL" DETERGENT THAT HELPS MAINTAIN PROPER OPERATION OF YOUR VEHICLE'S FUEL INJECTORS, AS WELL AS KEEPING THE VALVES CLEAN.

NOTE:
●THESE TIPS MAY BE USED ON ANY MODEL YEAR VEHICLE EXHIBITING THESE CONCERNS.

OTHER APPLICABLE ARTICLES: 91-8-13

SUPERSEDES: 94-12-3

WARRANTY STATUS: INFORMATION ONLY

OASIS CODES: 40200, 404000, 602300, 603300, 607000, 607400, 608000, 608400, 609000, 609400, 610000, 611000, 611500, 612000, 614000, 614500, 623000
RELATED INFORMATION
I have about 12 gals of premium gas 93 octane, and the balance; over 20 gals is Regular 87 octane. I did put 12 oz of octane booster and32 oz of Techron to clean the injection system. I have no idea what quality gas was previously used, normally I have had excellent results with BP up here in NYS. I will do a tune up eventually as the weather warms up and lets see what happens. Great article though. tks
 
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