Audi100S4 - Engine Cutting Out

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Wed 30 Jul 2014 12:59
Audi100S4 - Engine Cutting Out - antoniodevenice

My 20 year old Audi 100s4 has done 98,000 miles and is well maintained. Over past 3 years the engine has cut out on the motorway a few times at irregular intervals. All power is lost and the car sometimes restarts immediately but other times it does not and needs to be towed. It has been with Audi dealers and specialists and no one has been able to eliminate the problem. Possible causes such as dirt in throttle housing and replacement of crank shaft sensor have been addressed. Any advice or thoughts on possible causes appreciated.

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Wed 30 Jul 2014 13:02
Audi100S4 - Engine Cutting Out - Manatee

Coil(s)?

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Wed 30 Jul 2014 13:47
Audi100S4 - Engine Cutting Out - madf

Classic symptoms of:

failing crankshaft sensor - which has been replaced..

or camshaft sensor (if it has one).

Internal coils in the sensor heat up and the broken insulation or wiring means sudden loss of signal. So engine stops. OK when cold.. Or when vibration makes it all go again.

Hence no diagnostics warning.

Edited by madf on 30/07/2014 at 13:48

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Wed 30 Jul 2014 14:13
Audi100S4 - Engine Cutting Out - elekie&a/c doctor
With an Audi of this age,you could be looking at fuel pump /fuel injection relay issue.dry solder joints on the relay circuit board can cause erratic operation and engine cutting out problems.
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