CIS problem W107 350SL 1977 (UK Spec)

Dear All,

I have searched the forum problems with post start up, but can not find a similar problem.

When cranked the engine fires up immediatley, rev increase to about 1200 rpm and then after 5 seconds the revs drop to almost 200 rpm and engine sounds as tough it is about to stall. At this stage engine can be reved or driven without hesitation or mis-firing.

When hot engine drives and idles great, although I do have hot start problem.

New cold start injector resolved previous cold start problem. Thought above problem might be thermo time switch, but can new one be faulty. Warm up regulator is also new.

Have ordered fuel pressure guage to check control pressure and fuel pump pressure. Any ideas as to pressures.

Hot start problem should be cured with fuel accumulator which I have ordered, but can any one be kind enough to point out why post start should be problem? One thing I have noticed that if the vacumm hose from distributor is removed at contoured hose on air slide valve, rev's increase to level I would expect, but the air slide valve is new as well.

Has any one encountered faulty new components or is there another problem?

Parry Chana

[mendez300SD]

the fuel distributor contains a diferential pressure valve.located inside a hex nut (remove the air filter case) this valve is inexpensive and operates whit the fuel warm up governor presure variations, the noozle or injectors needs hi presure to operate in hot engine normal temp.this valve gets calibration adding a washers (stainless steel) .
REcently change a valve it comes whit instruction and a lot of washers . be carefull whit the piston, spring , is very important each part.
sorry gramatics
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