WJ no spark, no codes...CPS?

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Grand_Wag_85
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WJ no spark, no codes...CPS?

Post by Grand_Wag_85 »

Working on a '00 WJ (Grand Cherokee) that has suddenly lost spark. Has always ran real well but has been sitting a few months with a dead battery. Installed a fresh battery today and the Jeep endlessly cranks but won't fire. I can smell fuel after trying to start it, can hear the pump cycling. Also gave it a quick hit of starting fluid direct into the throttle body and nothing. Not throwing any codes.

Does this sound like the typical 4.0 CPS failure?
82 J10
77 J10 Golden Eagle 401
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You know it's bad when your car is on the EPA's 10 most wanted list!
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REDONE
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Re: WJ no spark, no codes...CPS?

Post by REDONE »

No, that sounds like the anti theft device. Try sticking the door key in the passenger door lock, then locking and unlocking the door three times in a row. Then try the key in the ignition.

I had to edit because I hate auto correct!
79 J-10 (Honcho Mucho) KE0LSU
304/Performance Fuel Injection TBI/MTA1/SP2P/Magnum rockers
T18/D20/D44s&4.10s/33" Mud Claws
Grizzly Locker Rear
4" front spring drop, 5" rear shackle flip
Chevy style HEI (ECM controlled)
Dolphin "Shark" gauges in a fancy homemade oak bezel
3/4 resto, rotting faster than I've been fixing it.
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Grand_Wag_85
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Re: WJ no spark, no codes...CPS?

Post by Grand_Wag_85 »

I'll give that a shot. I think this is one of those "genius" models with only one key hole in the driver's door and none on the other side. Should then work with the driver side door, right?

I don't think there's anybody that likes auto correct. :p
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77 J10 Golden Eagle 401
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You know it's bad when your car is on the EPA's 10 most wanted list!
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Grand_Wag_85
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Re: WJ no spark, no codes...CPS?

Post by Grand_Wag_85 »

Just watched a video on YouTube about the same issue on the same Jeep. I think you nailed it Redone! The check gauges light and anti theft light are lit up when trying to start it.
82 J10
77 J10 Golden Eagle 401
88 GW

You know it's bad when your car is on the EPA's 10 most wanted list!
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REDONE
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Re: WJ no spark, no codes...CPS?

Post by REDONE »

It should work in the driver's door, but that switch wears out first, which is why I recommended the passenger side. If the other side doesn't have a key hole though...I doubt drilling one yourself will work. :P
79 J-10 (Honcho Mucho) KE0LSU
304/Performance Fuel Injection TBI/MTA1/SP2P/Magnum rockers
T18/D20/D44s&4.10s/33" Mud Claws
Grizzly Locker Rear
4" front spring drop, 5" rear shackle flip
Chevy style HEI (ECM controlled)
Dolphin "Shark" gauges in a fancy homemade oak bezel
3/4 resto, rotting faster than I've been fixing it.
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REDONE
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Location: Lakewood and Bailey, CO

Re: WJ no spark, no codes...CPS?

Post by REDONE »

Let us know if it works! I spent the better part of an hour finding that tidbit for resetting the anti theft after thieves broke into my GC. It'd be awfully rewarding if the same knowledge paid off twice. ;)
79 J-10 (Honcho Mucho) KE0LSU
304/Performance Fuel Injection TBI/MTA1/SP2P/Magnum rockers
T18/D20/D44s&4.10s/33" Mud Claws
Grizzly Locker Rear
4" front spring drop, 5" rear shackle flip
Chevy style HEI (ECM controlled)
Dolphin "Shark" gauges in a fancy homemade oak bezel
3/4 resto, rotting faster than I've been fixing it.
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Grand_Wag_85
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Joined: Sat Aug 27, 2011 8:46 am

Re: WJ no spark, no codes...CPS?

Post by Grand_Wag_85 »

Tried the key turn trick and got an acknowledgement from the dome lights when I did it. Battery was low and I ran it out while cranking. Will have to try again this weekend.
82 J10
77 J10 Golden Eagle 401
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You know it's bad when your car is on the EPA's 10 most wanted list!
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Grand_Wag_85
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Re: WJ no spark, no codes...CPS?

Post by Grand_Wag_85 »

Did the lock/unlock trick and I was able to get it running. I haven't run it in about six months and it is CRANKY! Once revved to over 4000 rpms it smooths out and runs normal but anything below that it runs pretty rough.
82 J10
77 J10 Golden Eagle 401
88 GW

You know it's bad when your car is on the EPA's 10 most wanted list!
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Grand_Wag_85
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Re: WJ no spark, no codes...CPS?

Post by Grand_Wag_85 »

Bloody thing is acting up again. Changed the cps with no luck. The anti theft key trick produces no results.

I know it's getting fuel, I can smell it. Definitely no spark, pulled coils and verified
82 J10
77 J10 Golden Eagle 401
88 GW

You know it's bad when your car is on the EPA's 10 most wanted list!
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Shagoneer
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Re: WJ no spark, no codes...CPS?

Post by Shagoneer »

If it was the CPS it would shut off the fuel pump and the ignition system.
Maybe check the ASD relay. You may also try resetting the computer.
In the market for a new FSJ
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Grand_Wag_85
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Re: WJ no spark, no codes...CPS?

Post by Grand_Wag_85 »

How do you reset the computer?

Tried swapping the ASD relay with no luck.

Voltmeter is also dead?

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82 J10
77 J10 Golden Eagle 401
88 GW

You know it's bad when your car is on the EPA's 10 most wanted list!

bigun
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Re: WJ no spark, no codes...CPS?

Post by bigun »

Sitting here shaking my head, you are truly Murphy"s Poster Child!
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Grand_Wag_85
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Re: WJ no spark, no codes...CPS?

Post by Grand_Wag_85 »

bigun wrote:Sitting here shaking my head, you are truly Murphy"s Poster Child!

HA! This is the GF's Jeep lol
82 J10
77 J10 Golden Eagle 401
88 GW

You know it's bad when your car is on the EPA's 10 most wanted list!
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