928 no fire to the plugs
07-22-2001, 05:39 PM
#1
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Join Date: Jul 2001
Location: Madison, Alabama
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928 no fire to the plugs
I have just bought a '82 us model and was told it only needed a fuel pump,(ha,ha)Well, i tried to start the car,sure enough the pump would not come on,so I pulled the relay and hooked up a jumper wire and the pump started running! (whew!)But no spark at the plugs? I checked the cap and rotor,etc.Any suggestions?
07-22-2001, 07:12 PM
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Join Date: May 2001
Location: Hudson Valley NY
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With the key on ck for 12v at positive side of coil , no 12v ,fuse or wire
12v no spark, bad coil or capacitive discharge unit. With ignition on, the CDU is working properly when you hear a high whine.
12v no spark, bad coil or capacitive discharge unit. With ignition on, the CDU is working properly when you hear a high whine.
07-23-2001, 06:06 AM
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What about the relay itself? I have had a run of relay failures on my '80 over the past couple of years. The fuel pump relay has not failed yet, but I bought a spare which I carry in the glove box, just in case!!
If the pump does not run, the relay cuts power to the ignition.
Is the car fitted with a burglar alarm or immobiliser? My mechanic says that these are the cause of 80 per cent of 928s brought to him because they will not start. One good trick on the part of alarm/immobiliser installers is to power the fuel pump THROUGH the immobiliser module, instead of just using it to cut off the relay actuation circuit. The fuel pump, and the associated things powered through that relay, draw up to 13 amps, and will fry the immobiliser module sooner or later!!
If the pump does not run, the relay cuts power to the ignition.
Is the car fitted with a burglar alarm or immobiliser? My mechanic says that these are the cause of 80 per cent of 928s brought to him because they will not start. One good trick on the part of alarm/immobiliser installers is to power the fuel pump THROUGH the immobiliser module, instead of just using it to cut off the relay actuation circuit. The fuel pump, and the associated things powered through that relay, draw up to 13 amps, and will fry the immobiliser module sooner or later!!
