HELP! Heater Core Replacement, Now Jeep Won't Start - 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 > HELP! Heater Core Replacement, Now Jeep Won't Start

FS: 2007-2013 Jeep Wrangler "HALO" Angel Eye KitFlowmaster's Force II Axle-back exhaust system for the 201FS: Wranger BRIGHT License Plate LED! Just $3! Great value

Reply
Unread 11-22-2012, 01:23 PM   #1
cdcutsha
Registered User
1988 YJ Wrangler 
 
Join Date: Nov 2012
Location: Austin, IN
Posts: 40
HELP! Heater Core Replacement, Now Jeep Won't Start

Hello Everyone

Today, I replaced the heater core in my 1988 4.2 YJ. It actually went pretty well, only took a couple of hours. Got everything back together and now the jeep won't start!

It cranks (turns over) but it won't (fire) start. Worked fine yesterday, but now today after heater core change it's dead in the water.

Has anybody ran into this before... could use some advice.

cdcutsha is offline   Reply With Quote
Unread 11-22-2012, 01:32 PM   #2
stenyeart
Registered User
 
stenyeart's Avatar
1990 YJ Wrangler 
 
Join Date: Sep 2007
Location: Lewiston, Idaho
Posts: 195
Forget to hook something back up?

Are you getting fuel and spark?
stenyeart is offline   Reply With Quote
Unread 11-22-2012, 03:00 PM   #3
Luuca
Professional Novice
 
Luuca's Avatar
2005 LJ Wrangler 
 
Join Date: Apr 2012
Location: Corona, CA
Posts: 2,070
There is a ground wire that attaches up above the battery tray. It attaches to one of the bolts that you needed to remove to release the heater box. My guess is you probably either have a bad ground at that point because you forgot to hook it back up, or you painted that area and need to expose metal so the ground is better connected.
__________________
91 YJ "Alice" 2.5L AX5 D30/35, Rock sliders, Monsta Daughter&Dad Project Yellow Jeep Club Club #91

05 LJ Rubi "Ghost" 4.0L Auto NV241 Rock-Trac D44/44 lockers, 4" Currie Lift, 1" BL, 33s, hardtop
Luuca is offline   Reply With Quote
Unread 11-22-2012, 03:23 PM   #4
cdcutsha
Registered User
1988 YJ Wrangler 
 
Join Date: Nov 2012
Location: Austin, IN
Posts: 40
Getting fuel, i'm getting ready to tear back into it, to see what is going on. Ill check the grounds, and spark issues... idk.. it's just really weird.
cdcutsha is offline   Reply With Quote
Unread 11-22-2012, 03:41 PM   #5
Louie4
Powah Injanir
 
Louie4's Avatar
1993 YJ Wrangler 
 
Join Date: Aug 2008
Location: Raleigh, NC
Posts: 9,744
Start tracing back your voltage from the distributor to the coil. If you're not getting spark to the distributor see if the coil has 12 volts. Have you checked your fuses?
__________________
Lou

I have a jeep...and it is modified...I win.

YJOTM July 2012
YJOTM February 2014

Louie4's YJ Build
Poison Spyder Fender Install
Warn M8000 Rebuild Adventure
University of Georgia
Louie4 is offline   Reply With Quote
Unread 11-22-2012, 03:49 PM   #6
cdcutsha
Registered User
1988 YJ Wrangler 
 
Join Date: Nov 2012
Location: Austin, IN
Posts: 40
Double checked that ground wire that lucca spoke about, it wasn't ever removed.. thanks louie4 I will try that next.. the only other thing that I noticed, that there is a (relay)? near the battery box, where the power wire off the starter goes into,, it had gotten wet from the anti-freeze when I removed the heater core hoses from the firewall. that could be something but idk.. it's just really wierd, because I didn't really mess with anything electrical in this process.
cdcutsha is offline   Reply With Quote
Unread 11-22-2012, 06:49 PM   #7
Old4X
Registered User
1990 CJ7 
 
Join Date: Nov 2008
Location: Ga
Posts: 4,599
Check the wires to the start relay. It is the square box just below where you were working. There are several recent threads on how the wires are arranged if it isn't obvious when you inspect it.
__________________
Rust free YJ for sale. Need more room in barn.
Old4X is offline   Reply With Quote
Unread 11-22-2012, 07:59 PM   #8
TSEJEEPERS
Registered User
1993 YJ Wrangler 
 
Join Date: Dec 2003
Location: Morton IL
Posts: 4,890
Pull your distributer cap off, dry it off and spray it down with WD40.
You could have got mosture in it when you pulled the hoses.
__________________
93 YJ SOA 2" springs front, XJ springs rear w/main leaf added, High pinon 9 inch rear detroit locker front Dana 44 ARB 4.56 Gears, 36 inch Irok tires too much to list. www.mijc.org
TSEJEEPERS is offline   Reply With Quote
Unread 11-23-2012, 08:14 AM   #9
cdcutsha
Registered User
1988 YJ Wrangler 
 
Join Date: Nov 2012
Location: Austin, IN
Posts: 40
Checking everything today ( keeping fingers crossed ) hopefully it's something simple.
cdcutsha is offline   Reply With Quote
Unread 11-23-2012, 12:46 PM   #10
cdcutsha
Registered User
1988 YJ Wrangler 
 
Join Date: Nov 2012
Location: Austin, IN
Posts: 40
OK, checked everything! can't find the problem, I replaced the starter relay, coil and battery. The distributer looks good. idk still won't start just not getting a spark. Bought ready to pack it up and trailer down to my mechanic
cdcutsha is offline   Reply With Quote
Unread 11-23-2012, 08:47 PM   #11
Old4X
Registered User
1990 CJ7 
 
Join Date: Nov 2008
Location: Ga
Posts: 4,599
Can you fill out your profile so we know what equipment is installed on the jeep? Nutter, carb, stock ICM, etc.?
__________________
Rust free YJ for sale. Need more room in barn.
Old4X is offline   Reply With Quote
Unread 11-29-2012, 08:01 AM   #12
cdcutsha
Registered User
1988 YJ Wrangler 
 
Join Date: Nov 2012
Location: Austin, IN
Posts: 40
Got the jeep back up and running. It was the simplest thing, as they usually are.. The ECM somehow came loose when I pulled the heater box out, took the mechanic 30mins to figure it out. and back on the road I go. Thanks everyone for the help.
cdcutsha 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.