Engine dies when headlights are on - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Wrangler Forums > YJ Wrangler Technical Forum > Engine dies when headlights are on

Introducing MONSTALINER™ UV Permanent DIY Roll On Bed LineSavvy Aluminum BumpersThe RuffStuff "I can't go to EJS" Sale!

Reply
Unread 01-27-2014, 09:32 AM   #1
CKjeeps
Registered User
1987 J-Series Truck 
 
Join Date: Feb 2012
Location: jefferson city, MO
Posts: 291
Engine dies when headlights are on

I have a 89 YJ that when I turn the head lights on the engine starts to stumble and die. I have rewired all headlight wires from the firewall bulkhead to the headlights, nothing inside the cab yet. It had had to have many grounds replaced as the PO did a horrible job at fixing grounding issues. I can drive it fine without headlights. the turn signals and brakes work fine as do the dash lights. Could this be a bad switch? something else?

__________________
Check out my build. 95 wrangler 5.3 vortec, 14 bolt, 10 bolt, sm465, np205, 4 link rear, link front.

http://www.jeepforum.com/forum/f22/project-betty-white-1464639/
CKjeeps is offline   Reply With Quote
Unread 01-27-2014, 10:58 AM   #2
scraper
Registered User
1995 YJ Wrangler 
 
Join Date: Jul 2013
Location: Minerva, Ohio
Posts: 168
It could be a failing alternator. It's not putting out enough power, and when the lights come on they hog up everything the struggling alternator is producing. Just a guess though, you can take it to an auto store to have it tested for free.
scraper is offline   Reply With Quote
Unread 01-27-2014, 11:07 AM   #3
Michaelgoesrawr
Web Wheeler
 
Michaelgoesrawr's Avatar
1988 YJ Wrangler 
 
Join Date: Nov 2009
Location: Phelan, CA
Posts: 5,940
I doubt it's solely the alternator. You can drive your jeep for at least a half an hour on the battery alone. I'd go with a bad ground. Or a mixed ground causing interference.
__________________
Adopt your pets. Don't shop for them.

Help our dog Bo! https://fundly.com/give-bo-a-chance
Michaelgoesrawr is offline   Reply With Quote
Unread 01-27-2014, 11:23 AM   #4
Que89YJ
Web Wheeler
1989 YJ Wrangler 
 
Join Date: Apr 2008
Location: Detroit, Michigan
Posts: 13,703
No way is it an alternator issue unless you see the voltage noise dive when you turn on the headlights. What does the voltage guage say with them on/off?
Que89YJ is offline   Reply With Quote
Unread 01-27-2014, 12:04 PM   #5
Peety
Registered User
1988 YJ Wrangler 
 
Join Date: Nov 2013
Location: Piney, NJ
Posts: 66
I know that this sounds stoopid, but, mine did the same thing, it was the O2 sensor. Unplug it.
Peety is offline   Reply With Quote
Unread 01-27-2014, 07:19 PM   #6
laybackman
Bikini Bridge Inspector
 
laybackman's Avatar
1995 YJ Wrangler 
 
Join Date: Dec 2002
Location: Massachusetts
Posts: 5,600
Check the grounds by the headlights....


EDIT: Check the ground from the firewall to the dipstick bracket also....
__________________
"Once good behavior becomes the exception and not the rule your society has begun to fail…..we are there." laybackman

If your girl is throwing gang signs with her toes you're hitting the spot.

"If we cannot afford to take care of Veterans, then we should stop making them."
David C. Wilker Jr. USAF (RET)
laybackman is offline   Reply With Quote
Unread 01-27-2014, 07:45 PM   #7
Que89YJ
Web Wheeler
1989 YJ Wrangler 
 
Join Date: Apr 2008
Location: Detroit, Michigan
Posts: 13,703
Good call.
Que89YJ is offline   Reply With Quote
Unread 01-27-2014, 07:54 PM   #8
laybackman
Bikini Bridge Inspector
 
laybackman's Avatar
1995 YJ Wrangler 
 
Join Date: Dec 2002
Location: Massachusetts
Posts: 5,600
Quote:
Originally Posted by Que89YJ View Post
Good call.
Even a blind squirrel can find a nut once in a while......

Not that I'm necessarily right mind you!
__________________
"Once good behavior becomes the exception and not the rule your society has begun to fail…..we are there." laybackman

If your girl is throwing gang signs with her toes you're hitting the spot.

"If we cannot afford to take care of Veterans, then we should stop making them."
David C. Wilker Jr. USAF (RET)
laybackman is offline   Reply With Quote
Unread 01-27-2014, 08:16 PM   #9
Que89YJ
Web Wheeler
1989 YJ Wrangler 
 
Join Date: Apr 2008
Location: Detroit, Michigan
Posts: 13,703
Your not necessarily wrong either!
Que89YJ is offline   Reply With Quote
Unread 01-28-2014, 04:54 AM   #10
Mark05059
Registered User
1989 YJ Wrangler 
 
Join Date: Mar 2009
Location: quechee Vermont
Posts: 4,211
Quote:
Originally Posted by laybackman View Post
Even a blind squirrel can find a nut once in a while......

Not that I'm necessarily right mind you!
you cant be ALL right... you gotta be half left
__________________
1998 ZJ 5.2 Auto

1989 Wrangler Black Bone Stock 2.5l 5spd
/l , [____],
|---L--[]lllllll[]-
()_) ()_)==O=)_)
Mark05059 is offline   Reply With Quote
Unread 01-28-2014, 05:35 AM   #11
laybackman
Bikini Bridge Inspector
 
laybackman's Avatar
1995 YJ Wrangler 
 
Join Date: Dec 2002
Location: Massachusetts
Posts: 5,600
Quote:
Originally Posted by Mark05059 View Post
you cant be ALL right... you gotta be half left
Even if I were a blind squirrel!
__________________
"Once good behavior becomes the exception and not the rule your society has begun to fail…..we are there." laybackman

If your girl is throwing gang signs with her toes you're hitting the spot.

"If we cannot afford to take care of Veterans, then we should stop making them."
David C. Wilker Jr. USAF (RET)
laybackman is offline   Reply With Quote
Unread 01-28-2014, 04:28 PM   #12
halmc
Registered User
1992 YJ Wrangler 
 
Join Date: Jan 2006
Location: Tallahassee, Florida
Posts: 89
If everyone were right, no one would be left.
__________________
Evidence is the Kryptonite of the Pious
halmc is offline   Reply With Quote
Unread 01-28-2014, 05:36 PM   #13
laybackman
Bikini Bridge Inspector
 
laybackman's Avatar
1995 YJ Wrangler 
 
Join Date: Dec 2002
Location: Massachusetts
Posts: 5,600
Quote:
Originally Posted by halmc View Post
If everyone were right, no one would be left.
__________________
"Once good behavior becomes the exception and not the rule your society has begun to fail…..we are there." laybackman

If your girl is throwing gang signs with her toes you're hitting the spot.

"If we cannot afford to take care of Veterans, then we should stop making them."
David C. Wilker Jr. USAF (RET)
laybackman is offline   Reply With Quote




Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.