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

Sam76

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Is this the cylinder layout for a alloytec...
 

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shoieb

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Hi,
just wanted to add this works great. but yes the check power train lights stays on. thanks a lot.
One more thing to add, it's more easy if you cut the cable from the back and connect a copper U (small cable piece is U shape) in the Harness socket.
 

Tplunk

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Hi
Wondering if you can help , I have a vx 3.8 ecotec in a ford transit took it for airs first run on sat went well for the first 50ks but then started missing no power ect when I finally got home and pulled the plugs out numbers 1 & 3 , left bank and number 2 R/bank had melted would anyone have any ideas why other three plugs perfect
 

Tplunk

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Hi
Wondering if you can help , I have a vx 3.8 ecotec in a ford transit took it for airs first run on sat went well for the first 50ks but then started missing no power ect when I finally got home and pulled the plugs out numbers 1 & 3 , left bank and number 2 R/bank had melted would anyone have any ideas why other three plugs perfect
 

Gavcan01

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So I performed the splice after 2 odd years of procrastinating and persisting with erratic performance. Always cylinder 2 misfire. 300 and 302 codes every time this happened.
I could manage the vehicle by backing off and or changing down to 3 when the going got tough and revving it out a bit. Then it felt like it would clear out somewhat and run smooth - just right on the edge of throwing the codes again. Mostly noticeable at idle and slowly adding load to the engine in top gear when converter is locked, towing, AC ect.
Then on the weekend it finally just stayed. Threw the codes and wouldn't go away. Rough idle all the time very erratic all pointing to cyl 2.
Performed the splice to cylinder 2 to cyl 1 and took a little while to clear out and begin running smoothly and idling smooth but definite improvements. But the powertrain error and engine light wont go away. I have cleared the code and it disappears but comes on next engine start. Has anyone had this after a splice or could it be another issue?
Also drove around for a bit with my diag tool connected to laptop and notice o2 sensors on each bank a little strange. I would have thought they would read fairly similar but bank 1 is reading around .83 volts and bank 2 less than .1 at idle. Pic attached if anyone has any ideas.
If anyone would like to see data of any other sensor to help diagnose (if you can be bothered) let me know.
Anyway apart from the powertrain light the car seems to be running heaps better thanks for the help so far.

Edit - have already changed the plugs and coils before doing the splice.
 

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R.p

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Good day all
Gonna be trying this as my thing has nothing to injector 1 do you think it would work as it keeps throwing the power train issue
 

myxr8

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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
can someone tell me what coulor wire are on injector 3 & 2 please
 

robgm

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In reference to 60HOM's diagnosis steps in 2013; Probably stupid question but i'm confused what is faulty here in this statement below? Would i need to replace the injector in this case? "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.". Also, if possibly the coil pack has shorted then does that mean coil pack is faulty or or we talking about the wiring to it's plug?
Actually i have Cylinder 2 down and the ODB2 error is "P0202 Cylinder 2 - Injector Circuit Problem", troubleshooting it now.
 

Jaydizl

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I just did this and it has worked about to take it for a drive now thanks guys f### buying a new ecu
 
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