Spark plugs going bad

[Timmy390]

In the past 6 months I've had two Autolite spark plugs just stop working. Yes I know, why the hell are you running Autolite plugs? Seemed good at the time I guess.

Plugs are about 3 years old and have under 5000 miles on them. I had a come and go miss that would clear up once warm. It got worse and worse. Tracked it to #7 plug. Changed it and everything was great till last week. Had another miss. Tracked it down to #4 plug dead. I swapped both plugs around and the miss followed the plug so not wires/ignition or anything valve train related.

I've been lucky in my 53 years and have had more cars/trucks than the average person dreams of having. All kinds of engine configurations and plug brands. I've never ever had a plug go bad.

I bought a set of Motorcraft platinum plugs yesterday and put them in. All seems good so far.....The Autolites were copper.

Tim

 

[spap]

So the plug just broke. I come from a time too where you had to replace the plugs on your cars a lot more often from ford to more complex Alfa and Maserati engines
Wasn’t fouled but just stopped working ?
Sucks

 

[Timmy390]

The plug just stopped firing.....No visible cracks or damage or signs of fouling. Both started to misfile till warm and then after a bit just stopped firing all together. Cylinder dead as a hammer.

Verified the injectors were good, spark present through the plug wires and verified firing order. Moved the plug to a different cylinder and the issue followed the plug in both cases.

Engine build is what I would consider fresh. Less than 5K on the build. No burning of oil and no issues with the EFI that I know of. No codes and when all 8 are firing runs like a scalded dog.

I thought the first one was a fluke but after the second exact same issue it has to be the plugs are just crap. I bought them at the local parts store as I recall.....Then again, I MIGHT have bought them through RockAuto. maybe I got some china knockoffs?

Tim

 

[cs_88]

maybe I got some china knockoffs?

That’s what I was wondering.
Been running Autolite’s for years without a problem.

 

[oldiron]

Just a thought here. Look on youtube for "fordtechmakuloco" and he has a great video about counterfeit parts, specifically motorcraft plugs and coils.
We've all known about the decline in quality from cheap off-shore parts in recent years. Now they're copying the more expensive brands. i.e. paying premium prices for cheap knock-offs.
Greg

 

[ugly74]

Autolite plugs are made in China, so they have that going for them

 

[Timmy390]

Just a thought here. Look on youtube for "fordtechmakuloco" and he has a great video about counterfeit parts, specifically motorcraft plugs and coils.
We've all known about the decline in quality from cheap off-shore parts in recent years. Now they're copying the more expensive brands. i.e. paying premium prices for cheap knock-offs.
Greg

Seen some of that.....came across it when doing some research on "real" Motorcraft oil. I got a 14 Shelby GT500 and it only takes one specific oil per Ford and it's like GOLD. Special Motorcraft filter too. Was trying to make sure I was getting the real deal online.

Autolite plugs are made in China, so they have that going for them

I know.....heck but what isn't now days....I've ran a bunch of plugs over the years NGK, Autolites, Motorcraft, Champion, Bosch and some I'm sure I've forgotten about. I've never even had one crack that wasn't of my own doing.

Times have sure changed.

Tim

 

[mrdrnac]

Were they old style Autolite resister spark plugs like Autolite BRF-42's? If so, maybe your new modern style EFI ignition system is burning out the resisters and making the plug dead, too large of gap to jump where the resister was in the plug. Especially if they are cheap knockoffs. Just guessing.

 

[Timmy390]

Autolite 104 Copper

I'm using GT40P heads on my 351W from a 2001 Explorer so running plugs for that year Explorer (96-2001). The ignition system is 96 E350 van (distributor remote TFI, coil and wires) The plugs from the E7 heads that were on the W would not fit the P heads.

I did convert it to mass air from SD system that was on the van but don't think that would be a factor in this.

Tim

 

[oldiron]

Not likely. Sounds like you just got "lucky" and got a couple of duds. In 2011 I bought a new Mustang and had one plug fail at 800 miles, and another fail at 1400 miles. It happens sometimes.
Greg

 

[PickleJar]

They autolite but they don’t...

Sorry had to say it, I’ve used them on different vehicles over the years and only had one problem in a ford ranger

 

[75MIKE]

At least you were smart enough to find it in less than a year like yours truly.

Tore my carb apart more times than I want to admit and finally gave up as a gas dead spot when hi revving. Finally got it on a old school Sun computer and they found the Autolite spark plug in the first minute.Would run fine at idle to mid range , but would die off at high range.

Only one bad Autolite spark plug in many, many years and miles, however.

 

[spap]

Remember when the motor started running bad pulled the plugs cleaned them up and everything was fine haaa. I’m thinking counterfeit parts too

 

[Rustytruck]

20 years ago I had a set of autolites and after running them for a couple of years i was pulling the plug wires and 2 plugs the steel core inside the top porcelain pulled out with the wires. on time deal and the replacements were fine after that.

 

[Timmy390]

Sure is running good now. Took it for a spin across town and back. I'm not sure but some of the others weren't possibly missing randomly too.

Night and day difference.

Tim