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[megaomega123]

Just been for 30 mile run and still misfiring. It occasionally stops during acceleration and full power is restored. This is only briefly though. Read the codes and have it down to just cylinder 3.
The car is lpg and does the same on both fuels. I unplugged cylinder 3 lpg injector which made no difference. All the others changed engine tone when unplugged in turn.
All plugs were replaced about 4 months ago. Could it be 1 dodgy plug???
Should i just swap over 2 plugs and see if the misfire moves with the plug?

[Doctor Gollum]

Just been for 30 mile run and still misfiring. It occasionally stops during acceleration and full power is restored. This is only briefly though. Read the codes and have it down to just cylinder 3.
The car is lpg and does the same on both fuels. I unplugged cylinder 3 lpg injector which made no difference. All the others changed engine tone when unplugged in turn.
All plugs were replaced about 4 months ago. Could it be 1 dodgy plug???
Should i just swap over 2 plugs and see if the misfire moves with the plug?

Would be prudent for diagnostic purposes

[TheBoy]

Failing that, patch out LPG ECU from injector PoV, in case the LPG ECU has gone up the Gary Glitter.

[megaomega123]

Failing that, patch out LPG ECU from injector PoV, in case the LPG ECU has gone up the Gary Glitter.

Had a bad lpg injector on omega and the misfire didnt replicate on petrol.
I'm not sure how to totally patch out the lpg ecu. I tried unplugging it once but it wouldn't start on petrol!!!!

[TheBoy]

Failing that, patch out LPG ECU from injector PoV, in case the LPG ECU has gone up the Gary Glitter.

Had a bad lpg injector on omega and the misfire didnt replicate on petrol.
I'm not sure how to totally patch out the lpg ecu. I tried unplugging it once but it wouldn't start on petrol!!!!

If the LPG loom or LPG ECU is suspect, due to the way its a piggy back ECU and intercepts the signals to petrol injectors, it can impact running on petrol.

[megaomega123]

Failing that, patch out LPG ECU from injector PoV, in case the LPG ECU has gone up the Gary Glitter.

Had a bad lpg injector on omega and the misfire didnt replicate on petrol.
I'm not sure how to totally patch out the lpg ecu. I tried unplugging it once but it wouldn't start on petrol!!!!

If the LPG loom or LPG ECU is suspect, due to the way its a piggy back ECU and intercepts the signals to petrol injectors, it can impact running on petrol.

So how do I totally eliminate the lpg ecu from the equation?

[TheBoy]

Depends how the fitter intercepted the petrol injectors. Hopefully, on main injector loom plug (in which case, unplug the bits going to LPG), but more likely at the injector itself....

...without lpg, the petrol injector feed plugs straight onto injector. With LPG, that connector is unplugged, and the plugged into LPG loo to take signal back to LPG ECU. There is another wire from LPG ECU that then plugs into petrol injector.  Its a case of unplugging those connectors, and plugging the original injector lead (from petrol ecu) into the petrol injector.

[megaomega123]

I got 1 new spark plug. Took out number 3 and it had no electrodes left and was falling apart. Popped in the new one feeling delighted. Started her up and still the same, if not slightly worse 
Switched 2 injectors but the misfire stayed on cylinder 3.
Now what??

[megaomega123]

Just realised i tested the wrong lpg injector. Just checked three right one and it is dead. Did the spark plug kill the injector or vice versa?

[Stige]

Just realised i tested the wrong lpg injector. Just checked three right one and it is dead. Did the spark plug kill the injector or vice versa?

Bad Injector causing lean conditing burning out the electrode on the spark plug? Just a guess.

[megaomega123]

Think I've finally found the cause. I swapped over the injector plugs and the 'dead one' fired up. The misfire is petrol and lpg so it has to be the wiring from the lpg ecu to the injectors.
Would somebody please concur? It's been driving me nuts.

[Doctor Gollum]

Think I've finally found the cause. I swapped over the injector plugs and the 'dead one' fired up. The misfire is petrol and lpg so it has to be the wiring from the lpg ecu to the injectors.
Would somebody please concur? It's been driving me nuts.

All you've to do now is find the break

[megaomega123]

Even more stumped now!! Checked all the wiring to and from all injectors and nothing amiss. Rewired all the joins to be certain. Still get no signal from the petrol injector on cylinder 3. I followed 'TheBoys' idea of patching out the lpg but still had misfire and no signal on petrol injector 3.
I am really struggling now. If it's a faulty injector then surely the lpg injector would still work?
The lpg ecu reads from petrol injectors then feeds that back to lpg injectors so i presume the fault is between petrol injector and lpg ecu? All the wiring looks intact and good!

[cam.in.head]

are the injectors sequential/ individual on these or do they all fire at once like the old jetronic

[Doctor Gollum]

are the injectors sequential/ individual on these or do they all fire at once like the old jetronic

Same as 2.6/3.2 Omega