Fuel injection
How to Do a K-Jetronic Fuel Pressure Test on an R107
How to plumb a CIS gauge into an R107, read system, control and rest pressure, and what each bad number points to.
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Fuel injection guides – page 2
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Fuel injection
How to Check Lambda Duty Cycle on a 380SL or 560SL
How to read lambda duty cycle on a 380SL or 560SL, what the numbers mean, and how the mixture is adjusted from them.
Fuel injection
560SL EHA Valve: What It Does, Symptoms and Adjustment
What the 560SL's EHA valve does, how to tell when it is the problem, how to test and adjust it, and whether to rebuild or replace it.
Fuel injection
KE-Jetronic on the 560SL: How It Works and How to Diagnose It
How the KE-Jetronic (CIS-E) system on the US 560SL works, what each part does, the pressures to expect, and the order I diagnose faults in.
Fuel injection
What Gas Should an R107 Use? Octane and Ethanol
Fuel choice on an R107 is octane for the engine’s needs and honesty about ethanol’s effect on aged rubber and CIS components.…
Fuel injection
R107 Cold Start Valve and Thermo-Time Switch
R107 Cold Start Valve and Thermo-Time Switch diagram. ClassicMerc illustration — not a photograph. Cold-start valve and thermo-time switch provide a short…
Fuel injection
R107 Fuel Distributor: Rebuild or Replace?
As an Amazon Associate I earn from qualifying purchases. The fuel distributor meters CIS mixture. Rebuild versus replace depends on diagnosis and…
Fuel injection
R107 Fuel Accumulator: Symptoms and Test
The fuel accumulator helps K-Jetronic systems hold residual pressure after shutoff so hot starts stay civilized. Diaphragm failure shows up as hot-start…
Fuel injection
R107 Warm-Up Regulator: Symptoms and Test
The warm-up regulator (WUR) on K-Jetronic R107s controls control pressure during warm-up. When it fails, cold and warm drivability both suffer —…
Fuel injection
380SL/560SL High Idle or Rough Idle: Causes
High idle on a 380 or 560 is usually air leaks or idle control — not a mystery computer.