So I tried some E3 plugs, actually just put them on today. So far, I guess they're okay. I had to reboot the computer and then took it for a long drive to let it program itself (somehow my phantom code 36 came back after 3 months-- go figure). Anyway, no complaints and no praising for the plugs just yet, remains to be seen.

My old plugs were in fairly good condition for being about 15 years old. Let me rephrase that, since they were put in (2000-ish) car has traveled less than 10,000 miles.

So far what I accomplished was:
I got practice changing the plugs, discovered a coolant leak while I was at it (small drip from coolant level sensor), and cleaned it up a little -while I got dirty.
Performance wise, I hit 70 without really noticing- it felt more like 50 if that counts for anything.

 

So for the past week I have driving on e3's with leaky injectors (totally unrelated). Well anyway, before I changed them I was getting 13 mpg. I now get 17. The old plugs were still okay I guess for being that old. I can't wait till I get new injectors for it. When it is running tip top, I will know for sure how the l98 likes the plugs. So far so good though.

 

YES !! LOL... I bought them only once, then I switched to new AC Delco OEM plugs, guess what same performance at the track.

Now I just use NGK -9s.

Seat of the pants is just that; it's "perception" not factual.

Then you will understand ANY new set plugs is better than the tired old ones you replaced.

Back when leaded gas was still sold at any local pump you had to change your plugs every 12,000 miles (at least once a year) because the lead would foul the plugs.

Now we have plugs staying in service 40,000 miles or more. LOL the ones in my '09 Jeep have 77,000 miles on the them. but time and mileage will take its' toll on the plug.. mine were probably over due at 60,000 miles.

but guess what will go in.. the same OEM plugs than came out LOL

 

Well hopefully not the exact same plugs that came out. Lmao

For me e3 plugs are not seat of the pants difference. I mean I am in the middle, impartial that is. There is a difference, it seems to run smoother. The last time my car ran good was probably in 2000. ( I was 6). I have nothing to compare to. I guess we'll see what happens only time will tell.