trouble starting in cold - JeepForum.com

 
LinkBack Thread Tools
post #1 of 5 Old 11-14-2005, 01:21 PM Thread Starter
R3M3DYZ
Registered User
 
Join Date: Aug 2005
Posts: 19
trouble starting in cold

i have a 93 jeep cherokee with a 95 engine

car starts hard when the engine is cold it takes about 20 sec to start then when the check engine light comes on it starts. Everytime no prblems running or driving

however when the engine has been running for awile the engine will turnover either instantly or within 4 seconds.

fuel pump was replaced injectors were cleaned and new fuel pump.

what could be the problem

i was told a cold start sensor could be bad? if there is such a thing?

R3M3DYZ is offline  
Sponsored Links
Advertisement
 
post #2 of 5 Old 11-14-2005, 01:22 PM Thread Starter
R3M3DYZ
Registered User
 
Join Date: Aug 2005
Posts: 19
its a grand cherokee laredo
R3M3DYZ is offline  
post #3 of 5 Old 11-14-2005, 01:34 PM
-Joe-
Registered User
 
-Joe-'s Avatar
1995 ZJ 
 
Join Date: Jan 2005
Location: Lexington, KY
Posts: 4,634
Try the coolant temp sensor (If its a 4.0 its at the very front of the engine on the thermostat housing) I think its pretty much what some people call a cold start sensor..

- Joe -

'95 Jeep Grand Cherokee Laredo I6 4.0L
242TC - Extreme Engineering 2" Front Lift/1.75" Rear Lift - ES9000 Shocks + JKS BPEs
Moog Cargo Control Springs
Magnaflow Converter - Dynomax Muffler
235/75/15 AT Uniroyal Liberator Tires
-Joe- is offline  
post #4 of 5 Old 11-15-2005, 01:32 PM Thread Starter
R3M3DYZ
Registered User
 
Join Date: Aug 2005
Posts: 19
is it eas to install and is it a pricy part?
R3M3DYZ is offline  
post #5 of 5 Old 11-15-2005, 02:49 PM
-Joe-
Registered User
 
-Joe-'s Avatar
1995 ZJ 
 
Join Date: Jan 2005
Location: Lexington, KY
Posts: 4,634
No its not hard to replace. Unplug the connector, unscrew it. Put some teflon tape on the threads of the new one and do the reverse..

Its like $14 at autozone..

Theres actually two coolant temp sensors one at the back of the cylinder head and one at the front (The one that the computer uses is at the front, the back one is for the inside gauge)

Not saying its your problem but it is included in the array of startup sensors

I actually have a warm start problem, still unresolved


I found this info somewhere else..




----------------------------------------------------






Ignition Switch On:

This is an OPEN LOOP mode. When the SFI system is ACTIVATED by the ignition switch, the following actions occur:

* The PCM prepositions the idle air control (IAC) motor.
* The PCM reads atmospheric air pressure from the manifold absolute pressure (MAP) sensor and calculates the basic fuel strategy.
* The PCM monitors the throttle position sensor (TPS) and engine coolant temperature (ECT) sensor input. The PCM uses these inputs to modify fuel strategy.
* Intake air temperature (IAT) sensor is monitored.
* ASD relay is energized for 3 seconds.
* Fuel pump is energized for 1 second, unless engine is running or cranking.
* Oxygen sensor heating element is energized.

Engine Start-Up:

This is an OPEN LOOP mode. When the starter motor is engaged, the PCM receives input from:

* Battery voltage
* Crankshaft position (CKP) sensor
* Engine coolant temperature (ECT) sensor
* Intake air temperature (IAT) sensor
* Throttle position sensor (TPS)
* Camshaft position (CMP) sensor
* Starter relay

Based on these inputs the PCM will:

* Monitor crankshaft position sensor. If no signal is received within 3 seconds, the PCM will shut down the fuel injection system.
* Supply the injectors with a ground path, firing all injectors until the PCM determines crankshaft position.
* Determine proper ignition timing.

- Joe -

'95 Jeep Grand Cherokee Laredo I6 4.0L
242TC - Extreme Engineering 2" Front Lift/1.75" Rear Lift - ES9000 Shocks + JKS BPEs
Moog Cargo Control Springs
Magnaflow Converter - Dynomax Muffler
235/75/15 AT Uniroyal Liberator Tires
-Joe- is offline  
Reply

Quick Reply
Message:
Options

Register Now



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

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

Password:


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



Email Address:
OR

Log-in









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
Trouble Starting tommylee84 ZJ Grand Cherokee Forum 0 05-02-2009 06:41 PM
Trouble starting my 98 zj coloradojeeper ZJ Grand Cherokee Forum 2 07-22-2008 09:54 AM
No starting/hard starting in cold KrazysJeep ZJ Grand Cherokee Forum 3 10-23-2006 05:14 PM
trouble starting WhiskeyThrottle ZJ Grand Cherokee Forum 4 03-05-2005 12:14 AM
98 Trans trouble when cold.... ats1968 ZJ Grand Cherokee Forum 1 11-16-2004 11:20 PM

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