Mercedes: Mercedes 190 E intremittent no start and cutting out, mercedes benz 190e, fuel pump relay

Question
1989, Mercedes 190 E, 217,000 miles, Birmingham

The car drives well. On a few occasions it has refused to start again after parking the car. Eventually started about 15 minutes later. The engine cranks but does not fire. Also on a few occasions the engine has simply cut off whilst driving and I have had to coast along and pull over. Restarted after waiting about 15 minutes. Assume some sort of electrical fault as engine runs smoothly at all other times but the intermittent fault is worrying. Thank you.

Answer
Which one do you have?
190E 2.3L
190E 2.6L

When it fails:
* Do you have fuel pressure?
* Do you have spark?


Best Guess, it could be any of the following units.

Ignition Coil
Reference Sensor
Overload Relay
Fuel Pump

PART NUMBER SEARCH RESULTS WITH PRICES
Vehicle 1989 Mercedes Benz 190E 2.6
Part: Fuel Pump Relay
 Note:  
 Year: -1989
P2037-70282 Fuel Pump Relay Programa IN STOCK $137.38  
 
P2037-33032 Fuel Pump Relay Germany IN STOCK $132.36  

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