Novak Conversions Jeep Wrangler TJ radiator

97 Jeep TJ 4.0 will crank but not stay started

b1969k

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Dec 19, 2020
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south carolina
Hi all, Hoping for some guidance. I'm sure its posted here somewhere but couldnt find. The more i look the more i get to "information overload" haha

I have my sons jeep for sometime now (which i finally got back) , that i finally got around to tinkering with. Replaced the fuel pump and Computer (PCM) a couple of months ago. Before that, i replaced the CPS until the fuel pump finally died hence why i replaced the fuel pump.

So, battery is good, but when i crank the jeep it will start, but dies at almost immediately. The short video is the sound it makes to give more context. I heard it could be, cap and rotor, to IAC, TPS, MAP sensor etc. quite honestly, I'm more of a parts changer than a mechanic.

Just need some guidance on where to start first.

Than you all in advance.

BK
 
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Hi Jerry, yes sir, maybe a second or two at the max. No, it will not keep running if i hold the gas pedal down. I do not see an amber key icon.

Thank you for your quick reply.

BK
 
I was using a spare made key all metal, but i think the original key may be Black (just have to find). assuming you are talking about the back (boot) of the key
 
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I was using a spare made key all metal, but i think the original key may be Black (just have to find). assuming you are talking about the back (boot) of the key
Gray keys have a chip inside that TJs with the SKIM security interrogate to make sure it's the correct security key. If your TJ has the SKIM system it won't run without the right key, it'll allow it to start but it'll kill the engine within a couple seconds. Check the original key to see if it's black which indicates no SKIM system is present, or if it's gray which means your TJ has the SKIM security system.
 
Found the black ignition key, and tried it. Same thing happens. However, I'm not certain this is the original key as we've been the owner of the jeep for about 10 years. pic attached

if its not the original, how would i know if my 97 jeep has the SKIM System?

Thanks!

IMG_6687.jpg
 
if its not the original, how would i know if my 97 jeep has the SKIM System?

Start the jeep, and see if it dies after a few seconds.


:LOL:


But seriously there is a SKIM module but it's behind the dash, and I don't even know where exactly to tell you to look. I've never had a SKIM'd TJ. I also don't know of an easy way to tell, other than to start with the factory key and have it run right, and then start with a copy and have it die immediately. Did this just start? Or are you using an old copy you never tested and your son still has the original key? I doubt your SKIM just suddenly decided to enforce the policy after 10 years of being chill about it all.
 
Start the jeep, and see if it dies after a few seconds.


:LOL:


But seriously there is a SKIM module but it's behind the dash, and I don't even know where exactly to tell you to look. I've never had a SKIM'd TJ. I also don't know of an easy way to tell, other than to start with the factory key and have it run right, and then start with a copy and have it die immediately. Did this just start? Or are you using an old copy you never tested and your son still has the original key? I doubt your SKIM just suddenly decided to enforce the policy after 10 years of being chill about it all.

LOL, ITs the Same keys that we've always had since owning the vehicle.
Start the jeep, and see if it dies after a few seconds.


:LOL:


But seriously there is a SKIM module but it's behind the dash, and I don't even know where exactly to tell you to look. I've never had a SKIM'd TJ. I also don't know of an easy way to tell, other than to start with the factory key and have it run right, and then start with a copy and have it die immediately. Did this just start? Or are you using an old copy you never tested and your son still has the original key? I doubt your SKIM just suddenly decided to enforce the policy after 10 years of being chill about it all.

If it ever ran properly with the black key it does not have the SKIM (security key interlock module) sys

If it ever ran properly with the black key it does not have the SKIM (security key interlock module) system.
 
Same Key as always. However, I just talked to my son and he said, since the PCM was changed, it has has never started. I thought it had started.

???

So, could it be PCM related or is it just a coincidence that it wont start? I'm pretty sure it doesnt have a SKIM System.

Thanks
 
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Same Key as always. However, I just talked to my son and he said, since the PCM was changed, it has has never started. I thought it had started.

???

So, could it be PCM related or is it just a coincidence that it wont start? I'm pretty sure it doesnt have a SKIM System.

Thanks
With that new information it's likely the replacement PCM was programmed for a SKIM security system. Check with Mark at @Wranglerfix www.wranglerfix.com who will have a replacement PCM without the SKIM programming.
 
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Hi all, Hoping for some guidance. I'm sure its posted here somewhere but couldnt find. The more i look the more i get to "information overload" haha

I have my sons jeep for sometime now (which i finally got back) , that i finally got around to tinkering with. Replaced the fuel pump and Computer (PCM) a couple of months ago. Before that, i replaced the CPS until the fuel pump finally died hence why i replaced the fuel pump.

So, battery is good, but when i crank the jeep it will start, but dies at almost immediately. The short video is the sound it makes to give more context. I heard it could be, cap and rotor, to IAC, TPS, MAP sensor etc. quite honestly, I'm more of a parts changer than a mechanic.

Just need some guidance on where to start first.

Than you all in advance.

BK

Did it run after you put the computer in it?
 
Apparently not. I thought my son had it running after the PCM change, but I've had the jeep for a couple of months and just started tinkering with it. When i just asked him about it, he said it never would stay running.
 
Did it run after you put the computer in it?

Apparently not. I thought my son had it running after the PCM change, but I've had the jeep for a couple of months and just started tinkering with it. When i just asked him about it, he said it never would stay running.

There is a shitton of smoke pouring out of the barrel of that gun. Now we're all going to want to know why you needed to replace the PCM in the first place, and where you got the replacement from.
 
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@b1969k You can send the PCM into us and we can check skim and run it in a 97 to make sure everything is functioning properly with the pcm. You can call me at 866-888-7710 to discuss in further detail.

Thanks,

Mark
 
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Novak Conversions Jeep Wrangler TJ radiator