Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here XJ (84-01)
All OEM related XJ specific tech. Examples, no start, general maintenance or anything that's stock.

Bad CPS?

Thread Tools
 
Search this Thread
 
Old Mar 26, 2014 | 03:28 PM
  #1  
JeepMN's Avatar
Thread Starter
Seasoned Member
10 Year Member
 
Joined: Aug 2013
Posts: 452
Likes: 3
From: Duluth, MN
Year: 1999
Model: Cherokee
Engine: 4.0 I6
Default Bad CPS?

Back story - few weeks ago I was driving the Jeep like normal. Everything was running fine and seemed normal. I parked at a buddy's house for about 3 hours and came back to it not starting. It would crank over but would not stay at idle. We found out if you keep on the gas pedal it would stay at idle and eventually start driving like normal so I could make it home.

Next day I changed all spark plugs, plug wires, cap & rotor and bam it started like nothing ever happened. This was about 2 weeks ago. Now I'm stuck in my driveway with the exact same symptoms as before. So now I'm wondering what might cause this.. CPS? TPS?

Where would you start with this?

99 sport 4L inline 6

Other things that may or may not be related. 1) both times this happened the cd I had in my stereo was ejected from my deck the first time I started to turn it over. Don't know what that means.

2) Severely worse gas mileage the past 2 months or so, and no I'm not one of those guys whining about not getting 20 mpg but I'm seriously getting around 10 mpg.

3) Help.


Last edited by JeepMN; Mar 26, 2014 at 03:37 PM.
Reply
Old Mar 26, 2014 | 03:38 PM
  #2  
RTorrez1's Avatar
CF Veteran
 
Joined: Sep 2011
Posts: 4,172
Likes: 4
From: Riviera, Texas
Year: 1998 Sport
Model: Cherokee
Engine: 4.0
Default

The first thing you need to do is to get the codes read. if you can get it running head over to the nearest parts store and have them pull the codes. If you can't make it to a parts store try to find someone with a code reader. Once you get the codes post them exactly as they come up on the reader and we can go from there. The last thing you want to do is start buying a bunch of parts without know what you need. Let us know what the codes are as soon as you get them so we can try to get you back up and running.
Reply
Old Mar 26, 2014 | 03:54 PM
  #3  
JeepMN's Avatar
Thread Starter
Seasoned Member
10 Year Member
 
Joined: Aug 2013
Posts: 452
Likes: 3
From: Duluth, MN
Year: 1999
Model: Cherokee
Engine: 4.0 I6
Default

Originally Posted by RTorrez1
The first thing you need to do is to get the codes read. if you can get it running head over to the nearest parts store and have them pull the codes. If you can't make it to a parts store try to find someone with a code reader. Once you get the codes post them exactly as they come up on the reader and we can go from there. The last thing you want to do is start buying a bunch of parts without know what you need. Let us know what the codes are as soon as you get them so we can try to get you back up and running.
Only codes are P0758 and P0705. Probably not related..

Adds more confusion to the mix..
Reply
Old Mar 26, 2014 | 07:09 PM
  #4  
JeepMN's Avatar
Thread Starter
Seasoned Member
10 Year Member
 
Joined: Aug 2013
Posts: 452
Likes: 3
From: Duluth, MN
Year: 1999
Model: Cherokee
Engine: 4.0 I6
Default

Since I can get the vehicle to start by holding down the gas it has me thinking something is wrong with getting fuel to the plugs.

Could a bad o2 sensor cause this timing to be off? Or is it probably just CPS?

Reply
Old Mar 26, 2014 | 07:41 PM
  #5  
BimmerJeeper's Avatar
Banned
 
Joined: Oct 2012
Posts: 1,744
Likes: 2
From: USA
Year: 1998
Model: Cherokee
Engine: 4.0L i6
Default

These may give you some ideas....

https://www.cherokeeforum.com/f59/to...h-idle-155383/
https://www.cherokeeforum.com/f59/no...cklist-155216/
Reply
Old Mar 26, 2014 | 07:55 PM
  #6  
JeepMN's Avatar
Thread Starter
Seasoned Member
10 Year Member
 
Joined: Aug 2013
Posts: 452
Likes: 3
From: Duluth, MN
Year: 1999
Model: Cherokee
Engine: 4.0 I6
Default

Originally Posted by BimmerJeeper
Thanks for the links. Still don't know where to go with this, and I don't have the money to throw parts at it willingly.. doesn't help it's my DD and I have no other vehicle to use.

But more to add - I just went out and started cranking it over and it would only stay on/idle if I had my foot on gas pedal sitting above 1000 rpm. I then put it in gear and started driving away and 10 feet later I no longer had to keep the gas pedal down for it to stay at idle.

Do these conditions make sense to anybody?

No CEL, getting spark, getting fuel(don't know about pressure but I'm guessing it's getting enough since it started idling on its own after I drove away).. ?
Reply
Old Mar 27, 2014 | 01:03 AM
  #7  
DFlintstone's Avatar
CF Veteran
 
Joined: Aug 2011
Posts: 10,489
Likes: 24
From: Nor-Cal Coast
Year: 90,84
Model: Cherokee
Engine: 4.0,2.5
Default

89Lareto gifted me this IIRC. I like to post from time to time. I built my house for a little more than the $ for this guys meter. ($527 for the house) Friends, you might want to take a look at this HO, CPS CHECK>
http://www.cherokeetech.com/VBull/sh...agnosis-Videos

Last edited by DFlintstone; Mar 27, 2014 at 01:25 AM.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Tcq192
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
11
Dec 30, 2025 02:21 PM
jeefersjeepers
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
5
Nov 28, 2024 01:48 PM
carverdave
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
8
Sep 1, 2024 08:55 AM
Calikingcrawler
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
8
Sep 7, 2021 07:14 AM
xjnoah
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
0
Sep 16, 2015 02:29 PM

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 



All times are GMT -5. The time now is 06:50 PM.