spark @ coil, no spark @ plugs -
LinkBack Thread Tools
post #1 of 5 Old 07-08-2009, 04:34 PM Thread Starter
Registered User
Join Date: Jan 2009
Location: MN
Posts: 6
spark @ coil, no spark @ plugs

the jeep died on the highway and wouldnt start back up. it has spark coming from the coil but not from the plugs, can i rule out the crank sensor if it has spark at the coil? the connections under the disro cap have some corrosion possibly blocking spark from getting to the plugs. and whats the secret to getting the cap out from under the firewall? cant get it past the dipstick on the drivers side and the passenger side is blocked by all the hoses and vacuum lines

94GC52 is offline  
Sponsored Links
post #2 of 5 Old 07-08-2009, 05:30 PM Thread Starter
Registered User
Join Date: Jan 2009
Location: MN
Posts: 6
ok i got the new cap and rotor on and still no spark, i checked the coil and it doesnt spark with a spark plug and wire hooked up to it but if i take a metal ratchet and touch the coil terminal and something metal (alternator bracket) i can feel and see a little spark but not with a wire and plug hooked up to it.

im thinking its a weak coil since if it was the crank sensor there would be no spark at all right?
94GC52 is offline  
post #3 of 5 Old 07-08-2009, 07:54 PM Thread Starter
Registered User
Join Date: Jan 2009
Location: MN
Posts: 6
i took out my multimeter and i was getting about 10v pulsing to the coil. for primary resistance the coil reads .6 ohms and secondary resistance its 9.7k ohms so im pretty sure its a bad coil.
94GC52 is offline  
post #4 of 5 Old 07-08-2009, 10:35 PM
Registered User
2002 WJ 
Join Date: May 2009
Location: New Jersey
Posts: 792
Ok lets think logically here. The only point from the coil to the plug is the wire. First, make sure the plugs are good. Then if they are, its the wires.

A 6 yr old could have figured that out.

2002 WJ - Forest Green
gmp211 is offline  
post #5 of 5 Old 07-09-2009, 07:17 PM
Registered User
Join Date: Jul 2005
Location: Vermont
Posts: 284
Sounds like a weak coil that can't fire through the resistance of the wire. You said you could feel a spark, well a good coil should really give your hand a quite severe jolt! Coil is such a common problem, it's no waste of money to get a new one, just for reliability if it's age is unknown. Otherwise I'd say coil wire is bad unless you tried other plug wires on the coil also.

96 GC Limited V8 245,000 miles Scrapped
04 GC Limited 4.0 264,000 miles
96 GC 4.0 175,000
zjay is offline  

Quick Reply

Register Now

In order to be able to post messages on the forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page

Similar Threads
Thread Thread Starter Jeep Forums Replies Last Post
no spark to spark plugs??? jeepgcnp ZJ Grand Cherokee Forum 4 11-27-2011 10:08 PM
what spark plugs on the 4.0? madrabbitt ZJ Grand Cherokee Forum 7 11-18-2009 04:45 PM
spark plugs? RickL WK Grand Cherokee & XK Commander Forum 6 08-05-2009 12:19 AM
Coil Rack Wiring, no spark from plugs loofashay ZJ Grand Cherokee Forum 0 07-14-2009 12:23 AM
Spark Plugs baseball_coach WJ Grand Cherokee Forum 1 12-15-2003 08:28 AM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome