FQS - Fuel Quality Switch

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Position 0 is full counter clockwise

The FQS - Fuel Quality Switch
Adjustments for Fuel and Ignition Advance (Retard)

  Porsche 944 Porsche 951
(944 Turbo)		 Porsche 911 Porsche 
944S & 944S2

 

  USA  ML1.2
1982-1985.0		 ROW  ML1.1
1982-1985.0 		 USA ML3.1
1985.5-1989		 ML3.1 ML3.1 M2.1
Switch Position

Fuel

Retard

Fuel

Retard

Fuel

Retard

Fuel

Retard

Fuel

Retard

Fuel

Retard

0

0%

0°

0% 0° 0% 0° 0% 0° 0% 0° 0% 0°

1

+4%

0°

+3% 0° +3% 0° +3% 0° +3.1% 0° +3% 0°

2

-4%

0°

-3% 0° -3% 0° -3% 0° +6.3% 0° -3% 0°

3

+6%

0°

 +6% 0° +6% 0° +6% 0° -3.9% 0° +6% 0°

4

0%

-4.15°

 0% -2.77° 0% -2.77° 0% -2.73° 0% -2.79° 0% TBA

5

+4%

-4.15°

 +3% -2.77° +3% -2.77° +3% -2.73° +3.1% -2.79° +3% TBA

6

-4%

-4.15°

 -3% -2.77° -3% -2.77° -3% -2.73° +6.3% -2.79° -3% TBA

7

+6%

-4.15°

 +6% -2.77° +6% -2.77° +6% -2.73° -3.9% -2.79° +6% TBA
 

130 Teeth

 130 Teeth 130 Teeth

132 Teeth 

 129 Teeth 60-2 wheel

TBA - To be added                      ROW - Rest of World 

Switch position 0 is the stock position [full counter clockwise]

The Porsche 964 & 968 have no FQS 

 

This is an original BOSCH FQS adjusting tool [discontinued long ago]
on the left side is the triangular adjusting tool
on the right, the tool to punch through FQS cover

 

BMW M3 (E30), M5 (E28), M6 (E24) BMW 535i (E28), 635i (E24), 735i (E23)
Switch Position

Fuel Mixture

Ignition Timing

Fuel Mixture

Ignition Timing
0 0% 0° 0% 0°
1 +3.9% 0° +3.9% 0°
2 +10.2% 0° -3.9% 0°
3 -3.9% 0° -6.3% 0°
4 0% -3.1° 0% -3.1°
5 +3.9% -3.1° +3.9% -3.1°
6 +10.2% -3.1° -3.9% -3.1°
7 -3.9% -3.1° -6.3% -3.1°

116 Teeth Starter Gear

 116 Teeth Starter Gear

 

There is a 944 FQS Table in the "924/944/968 Frequently Asked Questions" document.  Do not use this table! It is for a 911 FQS, not a 944 FQS.

Early BOSCH Motronic DMEs are equipped with an 8-position Fuel Quality Switch. The switch allows the DME to adapt both fuel mixture and ignition timing for the quality of  gasoline available. The Fuel Quality Switch allows the user to correct fuel related engine problems.