lost spark in cylinder 1

[matt101590]

on a drive yesterday, put my foot down a little and lost a cylinder, upon more investigation I have little/no spark at cylinder 1

I am praying its not ignition module related does anyone have any other suggestions.

[tccrab]

Spark plug, spark plug wire and/or coil pack.


'Crabs

[matt101590]

sorry I should have said the plug is good

[tccrab]

Start with the simple things first, you're going to have to pull the plenum if it's not the spark plug.
Coil packs do fail, if you have a DVM, compare a working coil pack to #1's coil pack.
Only a very few DIS have failed that I've heard of over the years, and it's usually associated with a whole litany of other problems that kill the DIS.

[-=Jeff=-]

does the other Spark plug on that same coil fire?

[matt101590]

yeah number 6 does fire, i am gonna do the injectors coil packs and wires all at the same time while the plenum is off and just be done with it hopefully

[Bradjon]

I have had just one side of the coil fail on my car so don?t discount that coil pack being ok cuz the other plug fires . Jmho

[-=Jeff=-]

Having spark on the #6 tells me the DIS should be working..

[Paul Workman]

Just to add, the two plugs are wired in SERIES with the coil (aka "waste spark system"). So, in other words, whatever current is passing through one plug circuit is also passing through the other. Comparing the resistance across the primary and secondary sides of each of the coils is a good idea. But, too, the resistance to the #1 plug is normally greater due to the longer wire length; just to know so you don't become concerned about the difference in plug wire resistances (FYI). (However, because the plugs are wired in series, the differences in plug wire resistance would not affect the current flow.

Something else affecting coil output is the connection(s) leading to the coil pack. So, inspecting the connections to the DIS and the coil pack interface and a pulse of electronic cleaner while your at it would be worth doing "while your in there..."

I'm not trying to complicate things, but the thing about high voltage components like coils (especially), it is not uncommon for the insulation of the internal windings to breakdown over time/heat cycles. As result, shorting in the form of arching to ground OR other windings can occur, and a standard VOM will not necessarily detect an insulation failure. (A special high voltage OHM meter called a MEGGER is used to determine insulation breakdown.

Well...Not everyone has a megger handy, including many auto parts stores. And, tho I never suggest one start swapping out parts as a method of troubleshooting, in the case of suspected high voltage (coils) etc., but, when all else has been verified/eliminated, swapping coils might be the only last resort readily available (to us) to determine fault*.

* NOTE: But, keep in mind that the highest failure rate of electrical components occurs when they are first installed! (Referred to as "infant mortality" by statisticians and the reason why "changing parts out until the problem goes away" is a bad idea: often introducing new issues to the original problem which complicates the problem "exponentially!".)

OK... I'll shut up now. Just some things to stow away in the back of one's mind when troubleshooting "lectric chit".

[Young1]

Follow the routing of plug wire number one. Is it properly clamped behind the injector housing? Or is it lying around loose rubbing on something? Is it lying along side of the braided ground strap that is in that area? I saw this on a 1993. Looks like you have a plenum pull in your future Matt.