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Just replaced my below ohm spec injectors today and it's still misfiring and idling horribly.

Replaced the sparks, cleaned tps, maf and injector plugs, checked for vacuum leaks etc all seems fine.

Running a power balance test almost stalls the car it only just hangs on in there, the only thing I can spot that's maybe not right is the lhs o2 sensor voltage, it's higher than the right.

Any ideas?

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To see if you have O2-sensor problems, you can just disconnect them and see if it run better.

Its unlikely to be the O2 sensors, but disconnect them, the ecu will run a means setting. Check the board on the ECU, the injector points on the board are pretty much near the edge of the board and see if you have any terminals burnt out or corroded.

 

I had a similar problem with mine and found a pin burnt out on cylinder 4, failing that you could still have a harness issue, worth doing a continuity test back to the ecu from the injector plug

may not be the cause of the problem, but in the youtube video it looks your tps-sensor is not set correctly (in the video it looks like it's at 0.60 V @ idle) needs to be approx. 0.44V.

After setting the TPS to the correct voltage you will need to reset the TPS value in the ECU by unplugging the grey plug on the TPS with the engine running.

The engine will idle slightly higher once you unplug and then settle back to normal, this means the TPS setting has been cleared and you can plug it back in.

 

Next thing to check is the IACV value.

in the video it looks like it sits at around 30-40% while it needs to be at near 15% at idle.

The higher value can be caused by several things, but first try to adjust idle by turning the idle-screw on the IACV outwards.

While turning the screw outwards, idle should increase and IACV percentage should slowly decrease.

 

If you can't get it near 15% at idle or the idle doesn't seem to do anything while turning the screw, something else is wrong.

Then in most cases it's a split or loose hose somewhere around the balance bar area.

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Done compression test which was fine, its only a low milage engine.

I'll have a play with the tps and iacv at the weekend, I checked the ECU too looks brand new no corrosion or burnt contacts etc

I'm with Lymon - you TpS is way out. .44 is the norm what's recommended. The aicv is out too and should be 15%.

 

If you can't get the aicv down, you probably have a big air leak so it might be worth looking for that mate. Does it ever stall after boost or anything?

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