Benzworld.org - Mercedes Benz Discussion Forum - View Single Post - 404 suddenly starts running poorly

Two Tone · 05-14-2008, 02:12 PM

I guess it was more of a miss than a backfire.

I took off the dist. cap, everything appearred to be in order there.

I hooked up the timing light and noticed that the strobe was a little erratic. When I revved it up to the point where the engine would miss, it corresponded to the timing light. This seemed indicate an ignition problem.

I took the cap back off and the only thing I could think of to change was to disconnect the condenser wire which we had grounded back to the distributor body. After I installed the pertronix some time ago I noticed that some others had left it loose or cut it off. The instructions didn't even mention it so we screwed back on to the body of the dist.

Anyway, this seems to have fixed the problem but I'm still wondering why it went so long running just fine and then suddenly started acting up. Does anyone have a theory on what happened here? Have I partially fried the ignitor or the coil by leaving the condenser attached? I'm a bit puzzled. I really don't like it when I fix a problem but don't understand how. The problem often comes back to bite me somehow.

Anyone?

05-14-2008, 02:12 PM	#2 (permalink)
Two Tone BenzWorld Member Date registered: Dec 2007 Vehicle: 1969 Swiss 404 - 1977 Porsche 911 S Location: Nova Scotia, Canada Posts: 102	I guess it was more of a miss than a backfire. I took off the dist. cap, everything appearred to be in order there. I hooked up the timing light and noticed that the strobe was a little erratic. When I revved it up to the point where the engine would miss, it corresponded to the timing light. This seemed indicate an ignition problem. I took the cap back off and the only thing I could think of to change was to disconnect the condenser wire which we had grounded back to the distributor body. After I installed the pertronix some time ago I noticed that some others had left it loose or cut it off. The instructions didn't even mention it so we screwed back on to the body of the dist. Anyway, this seems to have fixed the problem but I'm still wondering why it went so long running just fine and then suddenly started acting up. Does anyone have a theory on what happened here? Have I partially fried the ignitor or the coil by leaving the condenser attached? I'm a bit puzzled. I really don't like it when I fix a problem but don't understand how. The problem often comes back to bite me somehow. Anyone? __________________ Two Tone ______ Reading the instructions - a sure sign of weakness and uncertainty. Last edited by Two Tone : 05-14-2008 at 02:15 PM.