98 f 150 4.6lt v8 Just hit 200,000 km on the engine..

New Bosch plugs were put in at 130,000km

Check engine light came on slowed down, pulled into shop, engine was vibrating..

Code read cylinders 3 and 8 are misfiring, took out the plugs, one plug the electrode and cap was cracked the other one the electrode and cap was black and crumbled into pieces upon touching. Replaced the plugs, replaced the wires.. Less vibration by about 70% but still misfiring..

Drove another 70km, and it went downhill from there. Lost all power, more cylinders started misfiring.. Got parked took out all of my plugs.. about 6/8 plugs the electrodes and insulator caps have evaporated and crumbled into my engine. THESE PLUGS ONLY HAVE 70, 000KM on them..

Running regular 87 octane fuel, never heated the engine, sparks was done by a shop...

So now my engine is hooped.. No compression. Haven't torn anything apart yet but I'm assuming my valves and cylinders are eaten up by these pieces..

In contact with the BOSCH company, they are sending it to higher up... I feel they are responsible for the total loss of my engine..

Talked to a million mechanics.. Said they've never seen anything like this in their life..

 

What Bosch plug number are these?

 

I used them on my 85' T-Bird and saw that starting to happen. The fine platinum wire inside the insulator. The wire started disappearing back into the insulator. I pulled them out and used Motorcraft and had no problems ever again. I won't use Bosch plugs on anything. There other products are very good.

 

Only thing I can read off of em are

Bosch: Platinum HR9DPY R3289


How many KM or miles on them when you seen this happening? I only caught it after it was too late.. Compression is down.. Engine=hooped..

I'm in contact with the company. Hoping they will pay for a new engine... (a girl can dream can't she?)

 

Sorry to hear it. Too hot a plug? Too lean a mixture? But to lean usually looks a lot different on the plug. It may come down to the plugs being damaged/cracked near the electrode tip. The far left plug in the 4 plug picture shows a crack forming in the porcelin near the tip? The shop's responsibility to do a good tune but they will probably jerk you around some as the plugs failed.

 

If you want to do research on this, go to SPARKPLUGS.COM.
Look at the Bosch data.
If your correct on the plug number, it is an obsolete number.
This is why I asked for the plug number because I suspected it was the cause.
Put in your year and bring up the reccomended plug number.
Down the left side is a trouble list.
Look at Pre igntion and the plug photo example of what that looks like.
It looks very much like what your photos show.
I think you got the wrong or old on the shelf plugs installed by the shop.
The pre igntion should have been heard by you as you were driving especially when this bad.
Pre igntion is an advanced form of Ping.
It goes from Ping to that stage at the beginning.
Pre igntion is the uncontrolled ignition of the charge by.. you guessed it.... hot plug parts not the actual ignition.
If this happens way too early in the compression stroke it results in tremendious cylinder pressures and heat.
Why is because the piston is still coming up to top dead center as the pressure rises too sharply that it pounds the plugs, the heads, the gaskets, piston crowns, the rods and the crank bearings and cylinder walls.
Not only does the uncontrolled combustion rise guickly but the pistons are still riseing and adds even more pressure, flame speed and heat to it yet.
The situation is akin to an explosion instead of a controlled burn.
There is no way the system design can cause such a thing to happen unless some one did this with the plugs.
Under controlled burn, if the ignition is too advanced the 'knock' sensor retards the timeing to protect the engine.
If there is uncontrolled explosion, ignition control/knock sensing has no effect such that it becomes a 'run-away' or out of control situation.
Sorry this happend to you.
There is always a reason why.
It's like doing an autopsy on the dead.
You can read exactly what happend by what you see.
Good luck with it.

 

Never use a thin wire tipped plug in a truck application.
The chances of it running too hot from heavey loading and vehichle weight is to great.
It may be gotten away with in a lighter car but not a truck.

Notice the ground straps in the photos.
They are still in tact by there mass and ability to get rid of heat to the plug shell.
They could still have run red hot and contributed to pre ignition.
Steel ground strap depending on it's composition would need over 2000 degrees to melt, and with that mass, cooling saves it from getting that hot.
900 degrees F is just a red color. As the temperature goes higher the color temp goes toward orange then into the white region until, the melting temp is reached..
Some steels when heated and cooled too many times gets brittle and begins to break off.

 

25,000 miles with correct EFI timing.

 

Bosch calls for HR9DCY or HG9DQP plugs for the 4.6L 1998. the HR9DPY is replaced by 4041 and fits 4.3L chevys. You probably have the wrong spark plug installed in your motor.

 

Have you found any help?