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Fuel Management

FUEL PUMP PRESSURE REG VALVE
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A recent experience on my KE Jetronic 180E W201 is worth repeating here because of the similarity with the K jetronic on the W116 6.9.

Background:
Replaced the fuel pump and filter coz the pump was noisy. The pump was supplied with the pressure regulator valve screwed in. The whole changeover was a cow of a job 1st time round.

Issue:
shortly after instlln, the car was hard to start. It was impossible to start when hot. It also developed a dangerous and unwelcome miss when very hot at speed....this would culminate in flame out when you slowed down say for an intersection.
The problem felt like fuel blockage or an intermittent electrical gremlin.

Diagnois:
Needless to say, KE jetronic is sufficiently different from the earlier K and to cut along story short, I figured out how to set up the fuel pressure gauge to see what was happening.

Quickly determined there was no residual fuel pressure when engine turned off. Instant suspect was the fuel pump pressure reg valve.
Damn!...back under the car, rip it all apart and viola!..removed the valve to discover the tiny nylon guts of it had disappeared?

Remedy:
I happened to have a new one in stock, fitted it up, tested AOK and zoom..back into business. It will start in a flash...hot or cold. It remains to be seen if the missing when hot has been remedied but it's a fair bet the 2 symptoms can be sheeted home to the same source.

Summary:
Nothing gripes me more than buying new parts and they bomb out, usually just out of warranty.[:(!]


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