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Discussion Starter #1
Both Ballast resistors on my 1976 280E are red hot, and the coil is very warm too.I cannot touch the resistors because they are so hot.
Surely this is not normal, as i only noticed this because of the burning smell that is the result of this heat.
Ive made no changes to the wiring at all.Im experiencing running problems(poor idle/popping from exhaust/lack of power).Starts great though, just wont idle right.Have renewed plugs/rotor arm/dizzy cap/fuel pump.Im thinking theres an issue with the ignition causing this?.

Im concerned about the heat of these resistors though.



'89 300E Turbo project, ‘85 Audi Coupe Quattro, ‘71 BMW turbo 2002, '73 BMW 2002tii, ‘67 Kaiser M725
17,641 Posts
Resistors on the warm side is normal. If the circular plug is bulged out on top of the the coil, replace.
If not, check the primary resistance between terminal #1 and #15

with starter resistance, 0.33 - 0.46 ohms
without starter resistance, 0.5 - 0.9 ohms

Secondary resistance terminals #1 and #4

with starter resistance, 7 - 12 K ohms
without starter resistance, 6 - 16 K ohms
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