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Unread 01-09-2009, 03:46 PM   #31
Anonymous6915
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how come the ones im taking out say 220 uf? is it ok to replace with 22 uf?????? for the 4.0...


Last edited by Anonymous6915; 01-09-2009 at 04:01 PM..
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Unread 01-09-2009, 06:04 PM   #32
Anonymous6915
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i just did the swap with the 22 uf and no go...did i fry it by trying it or should i replace with 220uf?...
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Unread 01-09-2009, 06:20 PM   #33
jackpal
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Originally Posted by Anonymous6915 View Post
heres a stupid question....wat happens if i dont disconnect the battery first?
Probably the same reason you should disconnect the battery before replacing or working on the alternator. Don't ask me how I know.
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Unread 01-09-2009, 09:21 PM   #34
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i just did the swap with the 22 uf and no go...did i fry it by trying it or should i replace with 220uf?...
check the dome fuse under the dash before anything else. for that matter check the ones under the hood too. if you pulled the computer without taking the batt cables loose first you could have popped them.
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92 YJ 4.0L Ax-15 231
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Unread 01-09-2009, 09:59 PM   #35
Anonymous6915
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ok i know where the fuses are located but which ones do i check? should i just start pulling and checking?


so does that mean that switching from 220uf to 22uf is ok? b/c i just went out and bout 3 220uf caps...i gotta get her running b/c i gotta drive her to the shop tom morning to do the tie rods...im not going to take off the 22 uf ones yet. first ill check the fuses...please let me know if i should got with the 22uf or 220uf...i got both but right now i have the 22uf's on there. they are like half the size of the original ones....plus the original ones had 220uf stamped on it...should i have replaced with 220uf and not 22?....
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Unread 01-09-2009, 10:20 PM   #36
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jus checked all my fuses and not the problem...alll fuses are good...any other ideas?
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Unread 01-09-2009, 10:33 PM   #37
sentinal02
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jus checked all my fuses and not the problem...alll fuses are good...any other ideas?
if 220 uf were what came out of there, then that's what i would replace them with. obviously they're there for a reason. just to confirm though, you are seeing the right symptoms to be doing this fix right? namely no check engine light when you first turn the key on, no fuel pump priming.
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RIP: '88 YJ 2.5L Ax-5 NP231
Posi-Loked. Herculined. Optima yellow top. 1" Shackle, 2" BDS. Cragar 397's Aussie front.

92 YJ 4.0L Ax-15 231
5" springs, 1" shackle 31's or 35's depending on my mood
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Unread 01-09-2009, 10:52 PM   #38
Anonymous6915
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yup same symptoms...just did the 220uf switch...ill let u know how it works out in a few...
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Unread 01-09-2009, 11:01 PM   #39
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nope no luck still no check engine light....iv been reading and cant find anything else that could be wrong...any ideas?....
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Unread 01-09-2009, 11:52 PM   #40
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nope no luck still no check engine light....iv been reading and cant find anything else that could be wrong...any ideas?....
if you haven't done it already, this thread will tell you if it's the computer itself or if the problem lies elsewhere:

http://www.jeepforum.com/forum/f12/91-hard-no-start-long-cranks-cold-explained-490788/

at the very least, i would check pin 9 on the computer for power when the key is on. if you're not getting that then the computer looks like it's going bad but it's really a wiring issue. other than that, if you've been through all the tests and it still comes up as the computer going bad, then it's always possible there's another problem besides the capacitors. they're hardly the only thing that can go wrong in there, but they are the more common problem. where abouts in NY are you btw? i might be able to lend you a hand.
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RIP: '88 YJ 2.5L Ax-5 NP231
Posi-Loked. Herculined. Optima yellow top. 1" Shackle, 2" BDS. Cragar 397's Aussie front.

92 YJ 4.0L Ax-15 231
5" springs, 1" shackle 31's or 35's depending on my mood
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Unread 01-10-2009, 05:56 AM   #41
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im on long island....franklin square...ill be going to buy a meter to try that out in a few...
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Unread 01-10-2009, 08:12 AM   #42
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I wish I had read this a year and a half ago. I was going though all the described symptoms with my YJ 4.0 and after much frustration I brought it to a garage which replaced the computer with a rebuilt one for hundreds of dollars.
Recently I thought I was going through the same problem again but realized that the symptoms were a little different. When I turned the ignition the "Check Engine" light would light but the starter relay would just rattle. I would let off and try it again and it would start right up. This wasn't every day. It was very sporadic. I don't think weather was a factor. Now it is to the point where either it will immediately start or there will be no or very low power. If I turn the ignition on with out starting it, the "Check Engine" light will either be fully illuminated or very dim. I checked for trouble codes and I got code 12 which is "Battery has been disconnected within the last 50 starts" which it hasn't. I checked the volts on the battery and I get 12 volts. I checked from the battery to the fuse block and I get 12 volts. I checked from the batter to the starter and I got maybe 8 volts. I am tempted to just replace the battery but would rather be sure before throwing money at a guess. Electricity is like magic to me. Does anyone know a way I could pinpoint the problem? By the way, I live in Massachusetts and it's been in the teens here recently and I haven't had the problem in about 4 or 5 days.

Thanks
Dan
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Unread 01-10-2009, 08:31 AM   #43
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just finished doing all those tests and everything is fine seems as though i did the "brain surgery incorrectly...
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Unread 01-10-2009, 11:20 AM   #44
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just finished doing all those tests and everything is fine seems as though i did the "brain surgery incorrectly...
either that or the caps weren't the problem. too bad you're not closer or we could try swapping computers to be sure. I'm about 3 hours from long island.
__________________
RIP: '88 YJ 2.5L Ax-5 NP231
Posi-Loked. Herculined. Optima yellow top. 1" Shackle, 2" BDS. Cragar 397's Aussie front.

92 YJ 4.0L Ax-15 231
5" springs, 1" shackle 31's or 35's depending on my mood
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Unread 01-10-2009, 11:22 AM   #45
sentinal02
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Quote:
Originally Posted by danl44 View Post
I wish I had read this a year and a half ago. I was going though all the described symptoms with my YJ 4.0 and after much frustration I brought it to a garage which replaced the computer with a rebuilt one for hundreds of dollars.
Recently I thought I was going through the same problem again but realized that the symptoms were a little different. When I turned the ignition the "Check Engine" light would light but the starter relay would just rattle. I would let off and try it again and it would start right up. This wasn't every day. It was very sporadic. I don't think weather was a factor. Now it is to the point where either it will immediately start or there will be no or very low power. If I turn the ignition on with out starting it, the "Check Engine" light will either be fully illuminated or very dim. I checked for trouble codes and I got code 12 which is "Battery has been disconnected within the last 50 starts" which it hasn't. I checked the volts on the battery and I get 12 volts. I checked from the battery to the fuse block and I get 12 volts. I checked from the batter to the starter and I got maybe 8 volts. I am tempted to just replace the battery but would rather be sure before throwing money at a guess. Electricity is like magic to me. Does anyone know a way I could pinpoint the problem? By the way, I live in Massachusetts and it's been in the teens here recently and I haven't had the problem in about 4 or 5 days.

Thanks
Dan
i'd start by changing your batt cables Dan. the battery to starter voltage at 8V is a huge drop and is usually indicative of a bad connection or cable.
__________________
RIP: '88 YJ 2.5L Ax-5 NP231
Posi-Loked. Herculined. Optima yellow top. 1" Shackle, 2" BDS. Cragar 397's Aussie front.

92 YJ 4.0L Ax-15 231
5" springs, 1" shackle 31's or 35's depending on my mood
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