I was on my way to the dragstrip this morning. Thought I would do some minor maintainence. I had not started the car since my last visit to the track, 1 weeks earlier. And I was running high 10's, but was running way too rich. I had pleanty for time to do some changes, 3 hours, and still make it to the track.


In an effort to increase my performance I did the following:

1. Changed out my eight N20 fuel jets, I was running way too rich.
2. Cleaned my Vortex air filter, it was black with dirt and grim.
3. Installed a new set of replacement NGK TR6 plugs.

Everything went very smooth. I finished by installing the new plugs, gapped at the same .035 as the original plugs. Took 45 minutes for this plug change. I then started the car in anticipation of leaving for the drag strip. The car ran terrible, sputtering jerking at aceleration, strong smell of gas was in the air. I examined the new spark plugs, I was amazed, they were black, and had a strong smell of gas. I mean 6 of the 8 plugs, looked like someone ran them through hell and back!
Covered with black soot.

I spent 5 hours trouble shooting this problem, even replaced the MSD plug wires (needed to anyway) but still I did not solve this problem.

Finally.after looking at everything imaginable, I gave up, and yanked the new plugs, and replaced them all with my original NGK's, which really did not look that bad to start with.

You guessed it, the car ran smooth as silk.!
I could have never guessed that the NGK plugs could be defective.
What idiots....made these.

Amazing! And depressing, I missed my track day.

I plan to go to the track next week, on good plugs this time!

Food for thought:
Always start your car just before and after each maintainence item performed. You will save valuable time!

Bruce1

 

Pretty strange to get that many plugs that are bad. Maybe someone dropped the box and cracked all of them.

 

That's weird , I've been running TR6'S in my Vettes since 2000 and never had a problem with these Plugs , Maybe You recieved a "Bad Batch" of some sort . :flag

 

It would be very interesting to measure the resistance from terminal to tip, and from terminal to the threads.

 

We did our best to measure the resistance on a meter.
We did get varied measurements. I am planning to send them back to the supplier next week.

At least 6 plugs were terminal, the other 2 not as bad, but clearly all were worse than what I had removed.

I was perplexed and surprised to say the least.


Bruce1

 

Hey Bruce, When you say it was running terrible... how terrible is that?
I'm currently having sputtering while under acceleration and I think it may be a plug but everyone else thinks it's not 'bad' enough to be a bad plug. I didn't modify them in anyway, they may be a bit old so It's a good idea to change it anyways but I'm wondering how 'terrible' yours was. Was it driveable? (Mine is driveable but I'd rather not drive it)

I feel alot of noise coming from my exhuast in the middle of the car, no banging or anything, just abnormal air flow.

TYIA
-Dan

 

Dan:
Although I did not drive the car, I could have, the idle was rough but running. I had NO real reason to drive it like that.
Sputtering on acceleration, YES, I felt it when I rev'd it to 4-5 grand.

Sounds like you could have a plug problem too.
I would remove the plugs and inspect them.
Have a set of replacements available as well.

 

My car has been running fine on the tr6s.


Those ORIGINAL plugs in the car were tr6s too right?

Im guessing bad batch.

 

Correct, TR6's.

 

None were cracked.

 

Just plain wierd........

 

I called Summit, where I purchased them, they were nice enough to send replacements at no cost. I bought these over 1 year ago.
They did not have to do that, They are a good company.

I am sending the plugs to NGK for evaluation as well......
How embarrasing, spark plugs that don't spark?... weird

Bruce

 

i had the same problem but i got a whole 600 miles out of them and then started running bad then to almost undriveable put in ac rapid fire and has run perfect ever since, called ngk headquarters and they said just take them back to where i bought them acted like they could care less! took them back got my money back i will never buy them again

 

If anyone needs TR6, for future reference, we stock them always. Supporting vendor

 

RedShift:
That is good to know.
But, can you take this to the next level?
Can you test them before you ship them to me?
Bruce

 

Good one. We have sold literally thousands and thousands of NGK plugs and have only had a very few of them bad. We would take care of you if that happened. Luckily they are not too difficult to change out.