Overheating after heater core bypass
Thread Starter
Seasoned Member
Joined: Aug 2010
Posts: 321
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From: Western Massachusetts
Year: 1994
Model: Cherokee
Engine: 4.0 6cyl
alright guys I'm dead in a parking lot I need help. I bypassed my heater core last night and today my jeeps running at 245. Any ideas of why this is happening and what I can do to fix it.
CF Veteran
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From: Broward County Fl.
Year: 1989 xj sport 2dr
Model: Cherokee
Engine: 12 hole bosch Injectors
CF Veteran
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From: Seal Beach, CA
Year: 1996
Model: Cherokee
Engine: 4.0 HO Straight Six
CF Veteran
Joined: Mar 2010
Posts: 47,923
Likes: 38
From: Broward County Fl.
Year: 1989 xj sport 2dr
Model: Cherokee
Engine: 12 hole bosch Injectors
CF Veteran
Joined: Apr 2009
Posts: 4,734
Likes: 12
Year: 2015, 2012
Model: Grand Cherokee (WK2)
Engine: 3.6L
Blown head gasket?
Cracked head?
Plugged cat/exhaust?
Probably nothing you can fix in a parking lot. Call a flatbed.
Cracked head?
Plugged cat/exhaust?
Probably nothing you can fix in a parking lot. Call a flatbed.
Last edited by Firestorm500; Mar 19, 2012 at 05:03 PM.
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Thread Starter
Seasoned Member
Joined: Aug 2010
Posts: 321
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From: Western Massachusetts
Year: 1994
Model: Cherokee
Engine: 4.0 6cyl
Originally Posted by freegdr
stuck thermostat,fans not working ,low on coolant plugged rad...why did you by pass heater core?
CF Veteran
Joined: Mar 2010
Posts: 47,923
Likes: 38
From: Broward County Fl.
Year: 1989 xj sport 2dr
Model: Cherokee
Engine: 12 hole bosch Injectors
Thread Starter
Seasoned Member
Joined: Aug 2010
Posts: 321
Likes: 0
From: Western Massachusetts
Year: 1994
Model: Cherokee
Engine: 4.0 6cyl
Originally Posted by freegdr
when its over heating when stoped and bumper to bumper traffic?
BUT it's fixed now replaced all the wires and grounds. New inline fuse and it turned right back on keeping it at 210 pretty steady. It'll work for now.
Thread Starter
Seasoned Member
Joined: Aug 2010
Posts: 321
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From: Western Massachusetts
Year: 1994
Model: Cherokee
Engine: 4.0 6cyl
Originally Posted by Firestorm500
That's great.
Good luck with the heater core.
Good luck with the heater core.
CF Veteran
Joined: Aug 2011
Posts: 1,031
Likes: 4
From: Blue Springs, MO
Year: 1993
Model: Grand Cherokee
Engine: 4.0L Laredo
Does your jeep have a mechanical fan with a clutch? A bad fan clutch is often the reason for overheating while sitting/idling or in slow traffic.
CF Veteran
Joined: Mar 2010
Posts: 47,923
Likes: 38
From: Broward County Fl.
Year: 1989 xj sport 2dr
Model: Cherokee
Engine: 12 hole bosch Injectors
Thread Starter
Seasoned Member
Joined: Aug 2010
Posts: 321
Likes: 0
From: Western Massachusetts
Year: 1994
Model: Cherokee
Engine: 4.0 6cyl
Originally Posted by freegdr
nope electrial grounds fixed a coolant problem...



