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ZUKIWORLD Discussion Forum => Suzuki 4x4 Forum => Topic started by: muskegtracker on June 12, 2007, 12:04:08 PM

Title: WHY YOU DIRTY COMPUTER! If I can't fix you I'll replace you with a carb.
Post by: muskegtracker on June 12, 2007, 12:04:08 PM
The 91 1.6L tracker doesn't run!

I put a different throttle body on hoping that would solve it.
I hot wired the injector.  It runs!  So no power to injector. 

I check:
     The injector is not getting any voltage.

I find out that the computers in trackers sometimes pack it in.
I searched and found that the capacitors in these old ecm's leak their electrolyte out after a few years.  So I replaced the one that was obviously leaking.  Still no luck.  There is another capacitor I left in, should I change it?  Any other ideas what it might be?

Might it be an under-dash relay?
Should I replace the whole computer?

Help please.....
Title: Re: WHY YOU DIRTY COMPUTER! If I can't fix you I'll replace you with a carb.
Post by: flea on June 12, 2007, 12:15:22 PM
great title !!!!!!


but i dont know !
Title: Re: WHY YOU DIRTY COMPUTER! If I can't fix you I'll replace you with a carb.
Post by: mrfuelish on June 12, 2007, 02:16:43 PM
The acid that leaks from the cap will eat the traces up, you have to put a sloder blob or bridge on it or a piece of wire across it if it is that large of a gap, yes pull the other and look under it for trace damage.
Title: Re: WHY YOU DIRTY COMPUTER! If I can't fix you I'll replace you with a carb.
Post by: urbanwheeler on June 12, 2007, 02:38:09 PM
I was having issues with mine, and thought about replacing the efi system with the samurai manifold and a weber carb. the only down side is that I live in california, and it would be hard to get it smogged (it would probably pass the emissions part, but not the stupid visual inspection(which serves no purpose but to be nazi)
Title: Re: WHY YOU DIRTY COMPUTER! If I can't fix you I'll replace you with a carb.
Post by: Uncivilized on June 12, 2007, 05:17:00 PM
The acid that leaks from the cap will eat the traces up, you have to put a sloder blob or bridge on it or a piece of wire across it if it is that large of a gap, yes pull the other and look under it for trace damage.
Right! you need to clean off the board and check the trace before you just plop in a new cap. You should change all of them too.
Title: Re: WHY YOU DIRTY COMPUTER! If I can't fix you I'll replace you with a carb.
Post by: muskegtracker on June 12, 2007, 10:00:08 PM
How do you check the trace?

Will it be visibly flawed?  Or do I need to hook up an ohm meter and test resistance?
Title: Re: WHY YOU DIRTY COMPUTER! If I can't fix you I'll replace you with a carb.
Post by: mrfuelish on June 12, 2007, 10:26:01 PM
If there has been any acid on it I would add a little solder to it. if you want to make it some what water proof you can add some marine spray to it also when you get done.
Title: Re: WHY YOU DIRTY COMPUTER! If I can't fix you I'll replace you with a carb.
Post by: Rhinoman on June 13, 2007, 04:55:42 AM
The ECU will usually work, although maybe not too well, without the caps. Failures usually occur when the tracks become damaged or the cap goes short circuit. It is possible that although the cap was leaking it may not have been the cause of the failure. The 12V supply to the injector is switched by one of the transistors (2SB1020) on the heatsink, that transistor could be faulty as could the drive to it.
The ECU is susceptible to damage from static discharge, you should always wear a wrist strap or you can destroy it just by handling the PCB. Usually though ESD damage leads to premature failure rather than instant failure.
Title: Re: WHY YOU DIRTY COMPUTER! If I can't fix you I'll replace you with a carb.
Post by: muskegtracker on June 25, 2007, 09:55:27 AM
It is Fixed!

It was the tracing at the capacitor.
I failed to check it closely on resoldering the new cap in.

I just made a little jumper and IT's ALIVE!

Title: Re: WHY YOU DIRTY COMPUTER! If I can't fix you I'll replace you with a carb.
Post by: Rhinoman on June 25, 2007, 10:01:33 AM
Excellent! and much cheaper than a carb too  ;D ;D
Title: Re: WHY YOU DIRTY COMPUTER! If I can't fix you I'll replace you with a carb.
Post by: muskegtracker on June 25, 2007, 11:23:01 AM
Can't complain about $.69.  Thanks for the input.
Title: Re: WHY YOU DIRTY COMPUTER! If I can't fix you I'll replace you with a carb.
Post by: kingzoo on June 26, 2007, 08:58:54 AM
   right on!glad somebody had some good luck!!
Title: Re: WHY YOU DIRTY COMPUTER! If I can't fix you I'll replace you with a carb.
Post by: Mike71 on June 26, 2007, 07:52:04 PM
man i am having this same problem as i type :( its lookin like 300$ to have it fixed to.

how difficult is it to get the computer apart to fix it? a few bucks would be much better then 300 :( lol
Title: Re: WHY YOU DIRTY COMPUTER! If I can't fix you I'll replace you with a carb.
Post by: urbanwheeler on June 26, 2007, 07:59:08 PM
The ECU will usually work, although maybe not too well, without the caps. Failures usually occur when the tracks become damaged or the cap goes short circuit. It is possible that although the cap was leaking it may not have been the cause of the failure. The 12V supply to the injector is switched by one of the transistors (2SB1020) on the heatsink, that transistor could be faulty as could the drive to it.
The ECU is susceptible to damage from static discharge, you should always wear a wrist strap or you can destroy it just by handling the PCB. Usually though ESD damage leads to premature failure rather than instant failure.

Could the capacitors be the reason why my tracker revs up to 2000 rpm and sometimes surges when I turn on the lights? maybe I should replace the capacitors. I also need to fix the transmission. it grinds going into 4th gear and sometimes pops out of 4th.
Title: Re: WHY YOU DIRTY COMPUTER! If I can't fix you I'll replace you with a carb.
Post by: Rhinoman on June 27, 2007, 05:41:36 AM
Could the capacitors be the reason why my tracker revs up to 2000 rpm and sometimes surges when I turn on the lights? maybe I should replace the capacitors. I also need to fix the transmission. it grinds going into 4th gear and sometimes pops out of 4th.

It could be or it could be an earth problem, when you turn on the lights the additional current could be causing a voltage change across a bad connection which could cause a difference in voltage between the ECU ground and the sensors ground.
If you're confident in your ability with a soldering iron then its worth doing. Even if the caps are good now they usually only last 5-10yrs. Preventative maintenance is always good. You do need to get good quality caps though, I have seen some sites that say that you should just get a high temp rated cap or a low ESR cap. The caps should have a ripple current rating equal to the originals, the ripple current rating is related to the ESR and temperature rating but not all caps are the same. On the ECUs that I have the caps are made by Nichicon (PJ series) or Rubycon (I forget). The datasheets for the caps are available from their webites.