87 260E no start - weak yellow spark - PeachParts Mercedes-Benz Forum

charjac · #1 08-09-2014, 07:37 PM

My 87 260 249K was running like a champ. I parked one night and the next morning she started but made it less than a mile before she had no power and died. It was rough starting but would run until I put it in gear and then would stall. Now no start at all.

Will not fire on a few shots of starting fluid

I changed the fuel filter, fuel pump relay and OVP.

I have fuel at the injectors, replaced screen in fuel dist. Removed and cleaned fuel dist. When I hold down the air plate and engine is cranked if I crack an injector there is great fuel volume.

Wires, cap and rotor have less than 5k on them. I removed the cap and it looks fine. Plugs have maybe 15K but look OK

I have a weak yellow spark when grounding a plug to the manifold.

So I have fuel, air, and some spark - Coil? CPS?

Any suggestions appreciated.

tecqboy · #2 08-09-2014, 09:41 PM

Check for arc tracks on the insulator plate in the distributor behind the rotor. Check for corrosion inside the connectors on the HT wires that plug into coil and distributor. Check the condition of the primary wires on the coil and the ground. After that much mileage, the coil itself would also be suspect to me.

charjac · #3 08-09-2014, 10:38 PM

Thanks. Will do 1st thing in the morning.

charjac · #4 08-10-2014, 12:41 PM

Swapped out the coil and the same thing. It will jump a 1/2 gap from the wire to the block. I still have yellow spark at the plugs. The insulator plate does not have any arc tracks but there is a small crack in the lip. I changed the cap and rotor a few miles ago with non bosch parts. Each plug is getting spark and they are wet with fuel.

My CPS reads 879 ohms at the EZL. I read somewhere that removal and cleaning it may help

Any ideas? could it be a cap failure? Spark and fuel - should at least sputter I would think. Like my wife keeps telling me. It ran just fine.

Thanks

Ivanerrol · #5 08-10-2014, 08:48 PM

879 ohms for the CPS at the EZL is right within spec.

We are assuming the wires, cap and rotor etc - all ignition parts are OEM Bosch or Beru.
No silicon leads.