spark and fuel no start? - Page 3 - 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 Grand Cherokee & Commander Forums > ZJ Grand Cherokee Forum > spark and fuel no start?

End of Summer Sale, 20% OFF!2007 - 2011 Jeep JK Long Arm Lift KitsIntroducing MONSTALINER™ UV Permanent DIY Roll On Bed Line

Reply
Unread 01-27-2013, 04:52 AM   #31
xrunndonex
Registered User
1994 ZJ 
 
Join Date: Dec 2012
Location: coffeyville, Kansas
Posts: 1,678
Quote:
Originally Posted by melk View Post
If everything else appears ok, that leaves the PCM.... have you cleaned the connectors and one of you hold them tight/wiggle them while you crank it?
And fuel pressure at 37 on rail well primed would if it could start it?

xrunndonex is online now   Reply With Quote
Unread 01-27-2013, 04:52 AM   #32
melk
Registered User
1996 ZJ 
 
Join Date: Sep 2009
Location: Charlotte, NC
Posts: 2,891
Yes has a black plastic cover and 3 main plugs underneath. Hot em with some electrical spray cleaner.
melk is offline   Reply With Quote
Unread 01-27-2013, 08:12 PM   #33
1slo_camaro
Registered User
1998 ZJ 
 
Join Date: Oct 2011
Location: Cape May/North East, NJ/MD
Posts: 1,072
hey dude so today i cant messing with my jeep and she fired up with the new motor. needs some fine tuning and some tinkering to get her back drivable again but the other motor would not start at all. so unfortunately i cant help out anything at all. because all my extrernal parts were swapped over. the only thing different was plugs and wires.... and if it was just plugs and wires i will be PISSED lol but i doubt that was the case. good luck with your hunting for an issue man.
__________________
1998 ZJ~~V.r 4~~4.0 with a bunch of fancy stuff that makes it look pretty sitting in the driveway.
PM me for 99+ intake manifolds for sale
$125-sandblasted and painted and shipped
1slo_camaro is offline   Reply With Quote
Unread 01-28-2013, 04:37 PM   #34
xrunndonex
Registered User
1994 ZJ 
 
Join Date: Dec 2012
Location: coffeyville, Kansas
Posts: 1,678
Quote:
Originally Posted by 1slo_camaro View Post
hey dude so today i cant messing with my jeep and she fired up with the new motor. needs some fine tuning and some tinkering to get her back drivable again but the other motor would not start at all. so unfortunately i cant help out anything at all. because all my extrernal parts were swapped over. the only thing different was plugs and wires.... and if it was just plugs and wires i will be PISSED lol but i doubt that was the case. good luck with your hunting for an issue man.
Think I know what it is but idk for sure the horn went off 2 times when cranking so thinking bad wire or something for the alarm that's cock blocking me.
xrunndonex is online now   Reply With Quote
Unread 02-06-2013, 01:33 AM   #35
99WJ539918
Registered User
1999 WJ 
 
Join Date: Aug 2008
Location: , Northern New Jersey
Posts: 1,400
I saw your post in the WJ section about the problems you're having with your car. I'm not sure about the ZJ's, but a problem like this would have me replacing the CKPS. This is a common failure on the WJ 4.0L's. Just because you're getting spark doesn't mean the CKPS is good. If you're getting gas and proper spark I would look into the smaller items before your PCM. I would unplug the connections and make sure they're clean, but after that I'd look somewhere else. This is, of course, not to say that this isn't your problem. It could even be your battery (I would return the one you bought and buy the proper one). Other than that, I'd look more about the fuel, use a noid light (plugs into the injector harness and blinks when the injector is grounded by the PCM). Other than that you're gonna have to take it to someone who can hook your car up to a scan tool and check more in depth.

I almost forgot, any hard codes?
99WJ539918 is offline   Reply With Quote
Unread 02-06-2013, 01:42 AM   #36
xrunndonex
Registered User
1994 ZJ 
 
Join Date: Dec 2012
Location: coffeyville, Kansas
Posts: 1,678
Quote:
Originally Posted by 99WJ539918 View Post
I saw your post in the WJ section about the problems you're having with your car. I'm not sure about the ZJ's, but a problem like this would have me replacing the CKPS. This is a common failure on the WJ 4.0L's. Just because you're getting spark doesn't mean the CKPS is good. If you're getting gas and proper spark I would look into the smaller items before your PCM. I would unplug the connections and make sure they're clean, but after that I'd look somewhere else. This is, of course, not to say that this isn't your problem. It could even be your battery (I would return the one you bought and buy the proper one). Other than that, I'd look more about the fuel, use a noid light (plugs into the injector harness and blinks when the injector is grounded by the PCM). Other than that you're gonna have to take it to someone who can hook your car up to a scan tool and check more in depth.

I almost forgot, any hard codes?
I would return the Battery but no receipt I tried. No codes I tried multiple times. I thought the ckps would cut off spark never thought about that. I'll Probly end up taking it somewhere after taxes if it don't run.
xrunndonex is online now   Reply With Quote
Unread 02-06-2013, 02:53 AM   #37
99WJ539918
Registered User
1999 WJ 
 
Join Date: Aug 2008
Location: , Northern New Jersey
Posts: 1,400
A bad CKPS would most of the time cause a no spark, but it's not a definite. You can unplug the sensor and plug it back in, just to check it out.
99WJ539918 is offline   Reply With Quote
Unread 02-06-2013, 06:27 AM   #38
Rich93ZJ
Registered User
1993 ZJ 
 
Join Date: Sep 2012
Location: Richland, Ga
Posts: 454
Quote:
Originally Posted by xrunndonex View Post
Think I know what it is but idk for sure the horn went off 2 times when cranking so thinking bad wire or something for the alarm that's cock blocking me.
Try locking then unlocking passenger door and hatch with the key. Are the lights flashing?
Rich93ZJ is offline   Reply With Quote
Unread 02-06-2013, 11:54 AM   #39
xrunndonex
Registered User
1994 ZJ 
 
Join Date: Dec 2012
Location: coffeyville, Kansas
Posts: 1,678
Quote:
Originally Posted by Rich93ZJ View Post

Try locking then unlocking passenger door and hatch with the key. Are the lights flashing?
No It's not the security system I wish it was though
xrunndonex is online now   Reply With Quote
Unread 02-06-2013, 11:56 AM   #40
xrunndonex
Registered User
1994 ZJ 
 
Join Date: Dec 2012
Location: coffeyville, Kansas
Posts: 1,678
Quote:
Originally Posted by 99WJ539918 View Post
A bad CKPS would most of the time cause a no spark, but it's not a definite. You can unplug the sensor and plug it back in, just to check it out.
I'll go check it out today. I hope it's the ckps gahh
xrunndonex is online now   Reply With Quote
Unread 02-06-2013, 03:27 PM   #41
Rich93ZJ
Registered User
1993 ZJ 
 
Join Date: Sep 2012
Location: Richland, Ga
Posts: 454
TPS can cause this condition also. What happens if you hold the gas pedal to the floor while cranking? The TPS is simple to test.

Backprobe from center pin with positive and put neg to ground. Turn ignition to run (dont start). Voltage at idle position must read greater than 300mv and gradually increase to around 4.1 - 4.8 at WOT. If the voltage is inconsistent anytime during the test, your TPS is bad. It must start above 300mv and gradually go to 4.1 -4.8 when you move the throttle by hand. Test and report back. Also, any time you replace a sensor make sure you disconnect the battery.
Rich93ZJ is offline   Reply With Quote
Unread 02-06-2013, 05:19 PM   #42
xrunndonex
Registered User
1994 ZJ 
 
Join Date: Dec 2012
Location: coffeyville, Kansas
Posts: 1,678
Quote:
Originally Posted by Rich93ZJ View Post
TPS can cause this condition also. What happens if you hold the gas pedal to the floor while cranking? The TPS is simple to test.

Backprobe from center pin with positive and put neg to ground. Turn ignition to run (dont start). Voltage at idle position must read greater than 300mv and gradually increase to around 4.1 - 4.8 at WOT. If the voltage is inconsistent anytime during the test, your TPS is bad. It must start above 300mv and gradually go to 4.1 -4.8 when you move the throttle by hand. Test and report back. Also, any time you replace a sensor make sure you disconnect the battery.
nothing changes when I press the gas. today I looked at the pcm very clean connections checked some wires then tried to start it. It sorta sputtered then I tried again and just cranked it wanted to start though maybe the battery is **** maybe I got a bad one which is rare I'll try jumping it when I look at the tps tomorrow
xrunndonex is online now   Reply With Quote
Unread 02-06-2013, 10:26 PM   #43
99WJ539918
Registered User
1999 WJ 
 
Join Date: Aug 2008
Location: , Northern New Jersey
Posts: 1,400
Quote:
Originally Posted by xrunndonex View Post
nothing changes when I press the gas. today I looked at the pcm very clean connections checked some wires then tried to start it. It sorta sputtered then I tried again and just cranked it wanted to start though maybe the battery is **** maybe I got a bad one which is rare I'll try jumping it when I look at the tps tomorrow
So it ran for a second and then died? Take your valve cover off...
99WJ539918 is offline   Reply With Quote
Unread 02-06-2013, 10:36 PM   #44
xrunndonex
Registered User
1994 ZJ 
 
Join Date: Dec 2012
Location: coffeyville, Kansas
Posts: 1,678
Quote:
Originally Posted by 99WJ539918 View Post

So it ran for a second and then died? Take your valve cover off...
I'm not mechanically inclined but when I get the valve cover off looking for stuck valves or anything that looked ****ed up right?
xrunndonex is online now   Reply With Quote
Unread 02-06-2013, 10:40 PM   #45
99WJ539918
Registered User
1999 WJ 
 
Join Date: Aug 2008
Location: , Northern New Jersey
Posts: 1,400
Yeah, have someone turn the engine (starter) with the valve cover off. See if everything moves.
99WJ539918 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.