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Unread 02-10-2010, 08:48 AM   #91
chucknutt
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Another satisfied customer. I was experiencing all the same issue's and like an idiot i started replacing everything i could. Even a new PCM(which didn't solve the problem kinda funny). Did this little swap of the capcitors on my old PCM and it worked. About an hour of time and $5.00. Thanks for the write up.

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Unread 02-10-2010, 09:57 AM   #92
Lumpymayo
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Quote:
Originally Posted by chucknutt View Post
Another satisfied customer. I was experiencing all the same issue's and like an idiot i started replacing everything i could. Even a new PCM(which didn't solve the problem kinda funny). Did this little swap of the capcitors on my old PCM and it worked. About an hour of time and $5.00. Thanks for the write up.
Sounds like the new PCM is defective, I'm hoping you got your money back.
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Unread 02-14-2010, 01:23 PM   #93
Hillbillydeluxe
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Just did this on my mothers 95 YJ which was having issues w/ no check engine light at start up and long cranks with no start. Worked great thanks so much for taking the time to post this.

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Unread 02-28-2010, 11:03 AM   #94
stone57
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This works

I can't thank you enough for posting this.I just repaired my ecm yesterday and it works great.You are a very smart man!!
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Unread 03-10-2010, 01:25 PM   #95
helogunner
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could this be the reason I have had a problem? vehicle ran fine a month ago. cold winter, have not started it in this amount of time. turn key, see cel, cel goes out after a second, hear click up front, no fuel to the rail. replaced relay, replaced pump/sender unit, fuel filter. still nothing. clicked ignition on 3 times, codes were disconnect battery, a/c fault, and that was it. i shot starting fluid in the intake and got fire so it is a fuel prob. any ideas if this will work?
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Unread 03-10-2010, 03:42 PM   #96
sentinal02
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Quote:
Originally Posted by helogunner View Post
could this be the reason I have had a problem? vehicle ran fine a month ago. cold winter, have not started it in this amount of time. turn key, see cel, cel goes out after a second, hear click up front, no fuel to the rail. replaced relay, replaced pump/sender unit, fuel filter. still nothing. clicked ignition on 3 times, codes were disconnect battery, a/c fault, and that was it. i shot starting fluid in the intake and got fire so it is a fuel prob. any ideas if this will work?
i doubt it. if it fired with the starter fluid then you've got spark which means the computer is most likely working. disco the fuel line at the fuel filter (pump side of the filter, not engine side) and then run it into a cup/can/container. have someone turn the key to run, wait a second for the pump to prime, and then to start to get the engine turning. you should get fuel out the hose into your container on both key positions. the first one will shut off after a second or two (priming phase) and then continuously while trying to start. if you get one, but not the other, I suspect your ignition switch may be bad. if you get nothing, then test the pump harness for 12V power and ground to see if it's getting power. if it is, then chances are either your new pump is bad or maybe you pinched a line or something installing it.
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Unread 03-13-2010, 09:55 PM   #97
r7069c
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I have just got thru replacing the caps on my ECU. 93' 4cylinder manual. I am waiting overnight for the silicon to dry. I will let you know if it works. My symptoms were no CEL,No Fuel Pump, NO spark. I had good power going to ECU. No power going to CPS.

It took me and a helper about two hours to replace the caps. I suck at soldering and have a crappy solder gun. If this works for me then anyone can do this. I promise to update tomorrow.
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Unread 03-14-2010, 07:36 AM   #98
r7069c
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Just put the ECU in and blew a cap. The cap that blew is marked in red. The black arrows show the way the stripe was facing. I didn't notice how the old ones came out. I guess I'm going to try and replace the cap that blew. If anyone can tell me if my caps are not pointed correctly I would appreciate it.
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Unread 03-14-2010, 08:58 AM   #99
Burnerman
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Quote:
Originally Posted by r7069c View Post
Just put the ECU in and blew a cap. The cap that blew is marked in red. The black arrows show the way the stripe was facing. I didn't notice how the old ones came out. I guess I'm going to try and replace the cap that blew. If anyone can tell me if my caps are not pointed correctly I would appreciate it.
looks like you put that one in backwards according to this>
Quote:
Well electrolytic caps have a gel in them that dries out over time and it can leak out. It is probably corrosive too. Like the original post mentioned, you have to install an electrolytic cap one way. If the cap has a long line on one side like the one in the pic then that is the negative side. Sometimes they will have a + on them. The +, of course denotes the positive side. So just look at which way the cap is installed that you take out. Electrolytics will also have a max voltage stamped on them like 25V or 16V. Make sure you buy caps that have a max voltage at least as high as the ones you are pulling out. If you take out one that says 25V then you can put one back in that says 25V or higher. Just as an FYI, if you install and electrolytic backwards the metal cap on the top of it will blow off like a little light weight bullet when it is energized. Just a little fun with electronics 101.
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Unread 03-14-2010, 09:09 AM   #100
r7069c
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From that quote I still cant tell which way the stripe is supposed to go other than the fact that the cap blew. I am about to replace it as soon as radio shack opens. I'm going to put it the opposite way and hopefully no more blown caps and engine starts.
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Unread 03-14-2010, 09:21 AM   #101
Burnerman
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The pic on the first page of this thread has the black strips pointed downward the way your pic oriented. Go to page 1.
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Unread 03-14-2010, 11:02 AM   #102
r7069c
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Just replaced the blown cap. Hooked up the ECU and still no start.
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Unread 03-14-2010, 11:08 AM   #103
sentinal02
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Quote:
Originally Posted by r7069c View Post
Just replaced the blown cap. Hooked up the ECU and still no start.
is it still exhibiting the same symptoms or did they change? did you follow this thread to isolate the computer as the problem?

http://www.jeepforum.com/forum/f12/9...lained-490788/
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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 03-14-2010, 03:47 PM   #104
Que89YJ
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The electrolytic caps do not like reverse voltage. The will blow almost immeadiately. The caps protect the rest of the module from reverse battery feed if you hook up the jumper cables backwards. They also surpress voltage spikes that come in on the battery and ignition feeds. Unfortunately they wear over time when exposed to extreme voltage changes in the vehicle. The diodes in the alternator surpress some of it but not all. That is why it is so important to becareful with connecting and disconnecting the battery leads with the jeeps electrical loads on and making sure the battery cables are securely connected.
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Unread 05-18-2010, 07:58 PM   #105
loonytoon
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ECU Fix

Tried this fix. Worked perfectly. Thank You jeep forum and Posters !
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