Darien

Checked under the hood when I got home tonight and I'm seeing flashes from the used OEM wires My new wires get here Tuesday, guess I'll have to wait.

Just out of curiosity, how do I perform the timing light check to see if only one side is firing?

Shane

All you have to do is put the timing light on each individual wire if the light fires then you have spark. Check all eight.

Darien

What about the section of wire under the plenims, can I run the engine with them removed?

Jim bailey - 928 International

Just some clarification.... First each coil and distributor and ignition secondary (the little unit under the black cover on the header panel in front of the radiator) fires 4 cylinders BUT TWO ON EACH BANK ! Limp HOME mode is generally considered to be the ability of the LH brained cars to run on a stored fuel program when the mass air sensor has failed. The twin dist euro and all 85> in the event of an ignition problem can and will run on 4 cylinders TWO ON EACH BANK. The pre ignition system monitoring relay cars < 88 IF running on 4 cylinder TWO ON EACH BANK continue to inject fuel into ALL 8 CYLINDERS ! Pumping air and fuel into the exhaust will quickly tune the catalytic convertor and pipes red hot and soon ,very soon the undercoating catches fire and typically burns up the fire wall insulation ,everything on top of the engine and melts the fuel lines then the HOOD . So running of 4 cylinders (two on each bank) is NOT LIMP HOME but if lucky limp to the fire station if it is close! Driving on 4 cylinders (two on each bank)is a BAD thing especially on 1988 or older LH cars. This issue of owners who for one reason or another insist on continuing to drive a car which has OBVIOUS problems caused Porsche to add exhaust port temperature sensors to two cylinders 4 and 8 in 1989 which the moved in 1990 to 3 and 7. These sensors compare temperatures and if there is too great a disparity they ASSUME that one of the ignition systems has a failure ( coil , coil wire , rotor, secondary exciter) and it uses the relay mounted on the outside of the LH package to shut of the fuel injection to the 4 cylinders (two on each bank) that it BELIEVES are not getting spark. That eliminates the risk of fire but according to PORSCHE the running on every other cylinder causes increased stress on the driveshaft so even on 1989 and newer running on 4 cylinders should NOT be considered "limp home" . That temperature monitoring system uses a RELAY that has the ability to shut of the fuel injection to 4 cylinders (two on each bank) as well as the other 4 cylinders (two on each bank) and of course can shut off ALL the cylinders when the relay fails.