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Easy and free fix for vz v6 engine miss (faulty ECU)

60HOM

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Hi everyone, this is my first post after following the site for awhile because my vz v6 developed a miss. Long story short it end up being a short in
No.6 INJ circuit, it was going to cost me $900+ for the ecu and $200+ to configure it :/

Being a mechanic myself I looked into it and found all I had to do was use one of the other INJ circuits to earth No.6 INJ, after splicing into INJ No.5
the miss disappeared :) with trouble free driving sence. So if anyone else out there has the same problem and wants to save $1000+ then replay on this post and ill detail how the carry the fix out, only takes about 15mins.

Cheers
 

99notout

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Yes please, if you have any diagrams or pictures that would be fantastic. Thanks for the offer! :beer chug:
 

greenacc

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How did you diagnose it ?
 

60HOM

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To diagnose is easy.

First disconnect each coil pack one at a time while the engine is running to find the missing cyl, replace that coil pack with another cyl's coil pack to see if the miss moves to that new cyl or stays in the same cyl.

If the miss moves then your coil pack is faulty, if it stays then and the spark plugs are good then its your inj which means your ecu has dropped out that inj due to a possible short from that coil pack.

Now to fix it without spending $1000+ on a ecu and tune

1. locate inj harness connection at the rear of intake manifold left side
2.if you look at the rear of the plug on the main harness side it should look like this.
brown/white pink/black brown/blue green red
yellow/black blue/black green/black

Cyl No.s

5 3 1 + +
6 4 2

3. Now lets say No.6 is missing, grab your test light and test No.6 wire but earth it on either the green or red power wires, the light should just stay on, you'll see after testing the other cyls that it should flash dimly.
3.now just cut No.6 (yellow/black) wire on the main harness side the splice it into No.5 wire (brown/white). its always good to splice it to the cyl earlier in the firing order eg No.2 to No.1 or No.4 to No.3. Then start engine
 

99notout

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Wow thanks for the reply and suggestion. Just a question, would that mean that the dead injector that you just spliced into and earlier injector wireing would get its impulse and inject the fuel into the cylinder too early??
 

60HOM

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Technically yes but no, your talking about a difference of about .01 sec at 4000rpm, it wouldnt really matter what injector the spliced into but I would just use the earlier injector because why not if your doing it.
 

diysv6

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Hi 60HOM,
I really liked the way you got around the failed injector switching from the ECU on #6 cylinder. Does the extra switching current on INJ#5 transistor switch exceed the transistor's specifications, or is there a safe design margin in the ECU? Would you stay with this rewire in the long term, or look around for a good, reasonably priced second hand unit?
 

maxcol

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Hi everyone, this is my first post after following the site for awhile because my vz v6 developed a miss. Long story short it end up being a short in
No.6 INJ circuit, it was going to cost me $900+ for the ecu and $200+ to configure it :/

Being a mechanic myself I looked into it and found all I had to do was use one of the other INJ circuits to earth No.6 INJ, after splicing into INJ No.5
the miss disappeared :) with trouble free driving sence. So if anyone else out there has the same problem and wants to save $1000+ then replay on this post and ill detail how the carry the fix out, only takes about 15mins.

Cheers
With your firing order the ++ are the drivers seat ?
 

vzladyowner

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Hi my vz has a miss and my mate who works for racq would really appreciate your knowledge on how to fix it for me
 
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