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https://yabb.autonerdz.com/cgi/yabb2//YaBB.pl >> >> multiply lightning strike https://yabb.autonerdz.com/cgi/yabb2//YaBB.pl?num=1443601311 Message started by autosparky on Sep 30^th, 2015 at 12:21am

Title: multiply lightning strike
Post by autosparky on Sep 30^th, 2015 at 12:21am

Mercedes V8 140 chassis
ignition system has 1 crank sensor, ignition module, 2 coils and 2 distributor(each does 4 cylinders)

The problem was backfiring, simple enough job to diagnose, unplug each king lead but it still back fires, after checking the firing order I found this
The cap towers were shorted

IMAG0696.jpg (515 KB | )

Title: Re: multiply lightning strike
Post by autosparky on Sep 30^th, 2015 at 12:30am

So I killed some time to see what's happening on each plug lead

Didn't think it was possible but I got spark from all four leads.
I also plugged in some dummy spark plugs to see spark, yes weak but 3 or 4 were sparking at the same time.

Couple of new caps fixed the problem

https://yabb.autonerdz.com/cgi/yabb2//YaBB.pl?action=downloadfile;file=right_se_backfire_cranking.psdata (10269 KB | )

IMAG0695.jpg (484 KB | )

Title: Re: multiply lightning strike
Post by royd on Oct 3^rd, 2015 at 5:23pm

Very nice capture! Another very common secondary issue on these is the ignition rotor carbon tracing to the steel flange behind.