Greetings Forum Members,


I need help in diagnosing a no start problem that seem to be due to not receiving voltage to the spark plugs.
The car is my 1985 280sl with the 110 engine.
I've gone through the testing proceedure according to the MB 110 manual
for the TSZ 8u switching unit.
Everything seem to check out ok.
When I follow the test proceedure for testing the ignition distributor transmitter section leads for ground connection via the green cable ,I get no ohm reading.
The manual states that each plug should read >/= 200k ohms.
The same test for the TST 4 unit states that these same leads should give a infinity reading.
What does an infinity reading on an ohm meter look like?
How can I tell which unit I have?
Supposedly after 1981 I should have a TST 8u unit, but this is a Euro spec car.
The coil is new.
The fuel pump relay plug tested ok per the MB manual.
Can the relay itself be tested with an ohm meter?
How might I test the ignition switch?
The engine will fire up for a couple of seconds and shut right down.
The plugs are wet, I'm getting fuel.
When testing for spark with my timing light I get a very erratic and some timey flashing of the light while cranking the engine.
Please HELP!!

Thanks,

Knarf

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72 350SL #69
73 450SL Parts Car?
78 450sl Parts Car
79 450SLC - Sold
1985 280sl
87 190E 2.6 - Donated
90 300E-Junked
97 E420

The distributor "green" lead must have a A/C voltage reading while the engine is cranking over. At least 0.3V A/c during cranking..

Do you get DWELL signal to the coil???

The terminals marked 15 & 31 at the ignition module must have enough power to turn on a headlight...current flow/amperage.

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