Cadillac Owners Forum banner

1 - 6 of 6 Posts

·
Registered
2002 Deville
Joined
·
33 Posts
Discussion Starter #1
I believe my ignition coils are going bad. Everyone keeps felling me to swap one coil pack to the other to test it that way but on my 2002 deville I have the ignition coil pack to where I cant just swap it with the next one. Is there any other way to test them? I get random misfires and irregular idle and slight stumble when acceleration. Iv swapd spark plugs to ac delcos and swapd the mass air flow sensor because I was told it could be that. So now I believe its the ignition coil pack. Any ideas?
 

·
Administrator
2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
Joined
·
68,551 Posts
Re: ignition coils

Your two coil cassettes (and their ICMs) are identical except for color. The swap cassette idea is that, if a coil in one cassette (of 4 coils) is bad, the miss would then move to the corresponding cylinder on the other bank.

A plug boot could also be cracked or carbon tracked - or even missing the internal connector spring.

You mighjt find a cassette at a junkyard - 2000 > 2003 are identical - or try www.car-part.com
 

Attachments

·
Registered
2001 Seville STS, 1990 Seville (RIP), 1972 Sedan Deville
Joined
·
26,323 Posts
You can test them with a VOM, the procedure is in the FSM, I don't know it off the top of my head.

You have a coil cassette set into a channel in each cam cover. They are identical except for color (front is silver rear is black). You can swap them.

Oops, sub beat me.
 

·
Master of the Dark Art of Diagnostics
2003 DHS - two-2002 DHS, 2003 SLS, 1995 Sedan DeVille, 1989 Coupe DeVille
Joined
·
19,293 Posts
Ok I will try that. Thank you so much
========================
I would recommend checking for Diagnostic Trouble Codes -
if you don't know how - go here and read the ENTIRE post -

http://www.cadillacforums.com/forums/cadillac-deville-1985-2005-including-1985/138257-how-pull-codes-dtcs.html

if you have any codes - post them here -
ALONG WITH THEIR DEFINITIONS -

------------------------

if you have a detectable misfire -
you will have an illuminated/blinking SERVICE ENGINE SOON light -
and a code P0300 - random misfire code -

------------------

and IF you do have the P0300 code -
our on-board code readers will not display WHICH cylinder/cylinders is/are misfiring -
only that there IS a misfire -

take the car to any large auto parts store - they will check your codes for free -

P0301 is a misfire in cylinder #1 - P0302 is cylinder #2 - P0303 is #3 - etc -

once you discover WHICH cylinder is misfiring - diagnosis becomes much easier -
 

·
Super Moderator
White Diamond '03 DHS (with DTS floor shift)
Joined
·
86,795 Posts
Is there any other way to test them?
Other than using an expensive coil on plug tester, you could pull the cassette, set it on the manifold, remove the boots and replace them plug wires. Then test the old fashioned way by pulling the wires one at a time and seeing if you see a change in the idle (misfire) or pull the wires one at a time off of the plugs and plug a spare spark plug into it while grounding the electrode and watching for spark.
 
1 - 6 of 6 Posts
Top