Coolant temp gauge spike. Thermometer?
Thread Starter
Seasoned Member
Joined: Oct 2010
Posts: 251
Likes: 0
From: Minnesota
Year: 99
Model: Cherokee
Engine: 4.0L
Hey my coolant temp on my dash spikes every couple of minutes. Is the thermometer bad? Anyone have a link to replace? Is it just a standard part at an auto store?
CF Veteran
Joined: Nov 2009
Posts: 8,172
Likes: 17
From: The Republic of TEXAS
Year: 1998
Model: Cherokee
Engine: 4.0L HO
Kinda hard to tell as the cooling system consists of several components that are all equally important to engine cooling but might want to start checking electrical connections at sending units/sensors/gauge, etc. Could be something as simple as low on coolant. When it spikes, maybe check it with a infrared temp gun pointed at the t-stat cover.
Last edited by djb383; Mar 11, 2012 at 05:18 PM.
CF Veteran




Joined: Nov 2010
Posts: 5,841
Likes: 117
From: In the middle of Minnesota!
Year: 1999
Model: Cherokee
Engine: 4.0
You need to determine if the spikes are real, or related to a false electrical signal which may be caused by a connection issue with the coolant temperature sensor located on the thermostat housing.
You need to resolve this ASAP. If real, overheating is hard on the engine, especially the cylinder head....can lead to blowing a head gasket or worse.
What is the history of cooling system maintenance? Always a good time to review. Radiator, radiator cap, thermostat, water pump, fan clutch, hoses.
Thread Starter
Seasoned Member
Joined: Oct 2010
Posts: 251
Likes: 0
From: Minnesota
Year: 99
Model: Cherokee
Engine: 4.0L
It looks like there is a little vent for the radiatior right next to the battery tray. got some coolant/stream coming outa there. Im not sure if it is real or not..temp reads normal most of the time..then spikes up for a few minutes then goes striaght back to normal. I was thinking that the thermostat is bad and it is 'venting' because it think my engine is overheating? History of mat. is good...no problems hoses, cap, radiator all look good. coolant level is steady at the full mark. I burbed the coolant system about a week ago becasue I was getting some air bubbles in there. Other than that I can't think of anything
Trending Topics
CF Veteran




Joined: Nov 2010
Posts: 5,841
Likes: 117
From: In the middle of Minnesota!
Year: 1999
Model: Cherokee
Engine: 4.0
CF Veteran
Joined: Nov 2009
Posts: 8,172
Likes: 17
From: The Republic of TEXAS
Year: 1998
Model: Cherokee
Engine: 4.0L HO
If u see coolant, u have a leak. When the motor cools, the lost coolant is most likely replaced with air. Air in the system can cause temp spikes.
CF Veteran
Joined: Nov 2011
Posts: 1,290
Likes: 0
From: phoenix az
Year: 1989
Model: Cherokee
Engine: 4.0l 6 cylinder
Originally Posted by MickDime
Hey my coolant temp on my dash spikes every couple of minutes. Is the thermometer bad? Anyone have a link to replace? Is it just a standard part at an auto store?
How tight is your radiator cap suppose to be... Tight enough so no pressure comes out at all?
CF Veteran
Joined: Nov 2011
Posts: 1,290
Likes: 0
From: phoenix az
Year: 1989
Model: Cherokee
Engine: 4.0l 6 cylinder
Originally Posted by stev-o
Mine was slightly spiking today
How tight is your radiator cap suppose to be... Tight enough so no pressure comes out at all?
Thread
Thread Starter
Forum
Replies
Last Post
shelby5041
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
39
Nov 7, 2015 01:22 AM
Cmcilm94
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
12
Sep 25, 2015 11:37 AM
Team SAW
Modified XJ Cherokee Tech
1
Sep 11, 2015 08:26 AM
daddytuck
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
0
Sep 7, 2015 07:50 PM
daddytuck
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
0
Sep 7, 2015 05:51 PM
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)



