front LH injector replaced still not firing, what it stopping my FlH injector??

[VTL67Calais]

Hi have replaced
-belts pulleys bla bra
-electical -leads
-plugs
-injectors
-coils

Motor sounds like one cylinder missing and when i pull on each injector lead the motor gets worse except ( number 1 cylinder )LRH when sitting in car. So my guess is its that but all the electrical is replaced, could the computer do this or is it wiring, i have pulled back the wiring and it looks ok unless its deep in the loom which is really protected.

There is no damage to the pins on the delphi i think its called unit? haven't got a new one of these as its just one injector? unsure please help, running out of time and need to drive 2000km home. Cheers for any help

 

[Turtl3]

Probably the dfi module considering thats about the only thing left

 

[VTL67Calais]

Cheers ill have to google it, found some other posts talking about fuel pressure but for the last cylinder and this is cylinder number 1 , some others have said a valve spring and also a inlet gasket but mine should only be a year or so old its the plastic **** one, but was done when my head gasket was done. Mechanic did it for $1200 so on a pension this time trying myself. Thanks mate ill look it up!

 

[lout]

pull the spark plug out and leave it touching bare metal
have someone crank engine and see if it is sparking
you can buy a noid light for around $20
which plugs into the injector harness and shows if the injector is being pulsed

 

[Immortality]

I'd be checking for power at the injector plug, then seeing if the ground wire get's earthed when the PCM tries to fire the injector. the L67 and ecotec are full sequential injection so one injector driver per injector so it could possibly be a PCM issue.

If it's not fuel than it could be spark however each coil fires 2 cylinders, if only one cylinder isn't firing it would suggest that it's not a coil/DFI issue but a lead or plug problem (which you have already replaced) which would then suggest it may be a mechanical issue. I'd remove the rocker cover and make sure the valves are moving correctly, if that is all good than a compression test may well be warranted.

 

[VTL67Calais]

great replies everyone!!

I'd be checking for power at the injector plug, then seeing if the ground wire get's earthed when the PCM tries to fire the injector. the L67 and ecotec are full sequential injection so one injector driver per injector so it could possibly be a PCM issue.

If it's not fuel than it could be spark however each coil fires 2 cylinders, if only one cylinder isn't firing it would suggest that it's not a coil/DFI issue but a lead or plug problem (which you have already replaced) which would then suggest it may be a mechanical issue. I'd remove the rocker cover and make sure the valves are moving correctly, if that is all good than a compression test may well be warranted.

When you mentioned the pcm I've ordered the usb elm327 as the bluetooth one paired but it couldn't connect to the computer, so maybe it is having issues, I've had random lights go on over time, and my airbag one is on, i did also have a big spark from the alternator to the big bar that attaches to the motor this happened when i put the battery back in after a repair and since had this issue i believe its got so bad i think, its been so hot working in the heat its like I'm dizzy.

I have an old compression tester from my old man i hope it works not sure how to so ill get a tube video , its how i lean a lot. Ill also check the springs as you said not sure what to look for but guessing if they look different in that number one cylinder.

REALLY APPRECIATE THE HELP!! Ill keep you all updated until the end result and lets hope i can make it home in the next few weeks with my budget and my car working :bomb: CHEERS!!!

 

[VTL67Calais]

Im sort of on my own here so ill try the other options first and will get one of those testers again, I had one before and now it died i think i blew a fuse in it. Cheers for taking the time to help, ill keep you updated.

 

[Immortality]

I'd be weary of cheap ELM327 units from ebay, many use cheap knock off IC's which the software recognises and then doesn't work correctly. Many are also not correct for the V6 engines as they use a different communications protocol than the LS engines.

Seeing as you have had a power spike it would suggest you could possibly have done some damage somewhere. With the valves/valve springs, you are indeed looking for broken springs, then start the engine and make sure the valves are all opening and closing the same or you could try turning the engine over with a bar and socket on the balancer bolt. It's OK to run the engine with the rocker cover off for a short period of time although you may get a little oil splashed about.

I'm supposed to be outside building a deck but I'm waiting till the late afternoon/evening to do my work otherwise I'd look like a big red lobster.

 

[Turtl3]

afaik...the elm bluetooth adaptors do not work with v6 or v8 commodores, other than the vt ls1

 

[Jxfwsf]

It is possible for a coil to fail on 1 side (although not very common), easiest test for this is to swap the leads on the coil post around, in this case 1 & 4, if the miss is now on the other cylinder then it's the coil.

The secondary is actually 2 coils with the center tap connected to a bolt holding the coil down.