Spark Plug time?

[oldsinner111]

I use to think,that when plugs started missing,its time to change,correct me if wrong.
I know wars have been started here over resistor's and non.
Read something today about that. No change in performance either ones.Matter of fact resistors spark longer than non.If you have computer controlled ignition,non resistor can burn it up.
Case in point, man had motorbike that he ran non resistors in. Bike was fine,the wire burnt up, and he attach what was left directly to plug. ECU burnt in no time,Once he got another he changed to resistor.
Anyways fuel mileage sucks lately,I'm thinking plug time.
Also my car has a MOT valve. It sucks vapor from fuel tank.But I noticed for the first time fuel in the hase. Valve works as I keep it clean.Not running rich.M104.994

[Duke2.6]

Is the OE recommendation resistor or non-resistor type?

...don't know about the M104, but I can tell you for sure that running resistor plugs (rather than the OE non-resistor type) in a M103 results in more idle misfires and considerably increases the HC count in emission testing - enough to barely pass or even fail the test.

The nominal life of a common copper core, two-dollar plug, resistor or non-resistor type, is about 30K miles and 30K miles is the recommended change interval for M103, but inspection may reveal they are okay to continue using.

You should always use the OE recommended plug or equivalent in another brand for normal road driving. The problem is that finding non-resistor plugs can be tough because Bosch no longer manufactures them. If the OE plug recommendation is a resistor type that's what you should use.

Duke