Wrong spark plugs or what ?

[chris59]

Hello,

I've got a misfire problem on my 350I, cold or hot : swapping rotor arm, distributor cap, ignition module (the one screw to the ignition), plug wires, or coil didn't solve the problem.

All injectors work well, disconnecting the cold start injector makes no difference.

The 8 spark plugs are new NGK BPR5 ES : if I unplug one plug wire at a time, creating an electrical arch between the plug and the wire, the engine work correctly for a while.

Could the plugs model be wrong, ie too cold or too hot ?

Best,

Chris

[chris59]

Hi Adam, how are you ?

Thanks for your reply !

The plugs are correctly gapped, and the timing is good : it was working perfectly before I had some problems who, finally, were caused by the carbon contact in the middle of a (crappy) distributor cap.

[chris59]

But the wizard problem remain, so it's not the plugs neither...

[chris59]

Good idea, but ALL the plug (and coil) wires are brand new, and from the best quality, no cheap repro here.

[chris59]

Good idea, I'll try this next weekend !