Spark plug Bosch or Autolite
I changed the spark plugs to Autolite Double Plat plugs from Autozone. The smoke cleared up and it is MUCH easier to keep cranked in the cold (30's F) in the morning. It still has a very light stumble every few cycles and a louder engine idle than I'd like, but runs good and seems to be much better.
Bosch W7DTC plugs were the best, caint get them no mores, use NGK BP6ET plugs instead.
Bosch F3cs @27psi no issues and no gapping
I pulled the plugs this morning and replaced them with Bosch cooper plugs, the only match that was available in local Autozone. There are no more misfires (for now), which makes plugs the culprit.
Currently Running Bosch - Fusions - for Spark those seem to have Smoothed the Motor - 1 step Cooler .
I'm using the OEM Bosch spark plug. I gapped mine to 0.024" as per Bentley and the car seems to run fine.
Worst case of electrode wear I've seen was on a set of Bosch 3-electrode plugs in a VR6. Plugs were so far gone, that five of six had triangular shaped center electrodes. Really thought I was gonna gall the head threads they'd been in so long.
I found Bosch platinum plugs misfired intermittently on GM v8s with the optispark distributor despite being identical to the Delcos.
I did the plug change for the first time on my Tig. Pretty easy and took maybe 30 minutes. tricky part was getting the wire harness/clips to release from coil packs. Just be patient and use a small screwdriver. FWiW, I used Autolite Iridium plugs cuz my local NAPA dealer was out of the NGK's and recommended these. The quality was really bad on my set.. The cathode (curved portion of the plug) was significantly off axis, misaligned. One plug was bad enough that I returned it for an exchange. These plugs get high reviews on Amazon, so I kept them in without any problem but will be going back to the OEM NGK's next time. My old plugs looked very good for 45K miles.
Lesson learned: DO NOT EVER EVER EVER USE BOSCH PLATINUM (STANDARD TIP) SPARK PLUGS IN YOUR VR6 ENGINE.... THEY JUST DON'T WORK!
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