us gm bosch ecu in au ve series 2 3.6 ?

[amiga68000]

thanks for help so far.
simple question in why does ecu say p0301 all the time when ive swaped injectors and coil and plugs. no other cylinder ever comes up ?
is it lieing to me. or is it dumb software in ecu or is it legit ?

[Holden202T]

I had the same issue with a VZ Alloytec, to be sure if it was a cylinder or coil etc I swapped the coils from cyl 1 to 3 and the error changed to that cylinder in the DTC's .... that's when I changed the coil and fixed it .... but if you have already changed coils that's going to make it harder....

but if you can change things like that or injectors to another cylinder that might help you determine what part it is.

[antus]

It could be slightly lean and something to do with airflow in the head so that cylinder is slightly leaner and struggling more. Or it could be the ecu.

[amiga68000]

as said earlier. i have a new coil on 1 and new plugs in engine and swapped and cleaned injectors on 1

so 1 has new plug ,new coil, and swapped and cleaned injector still same code scanned and reset many times to verify.

and the was a place in the scan computer software that said possible faulty ecu !

all intake values have build up which i dont like, really look like they need a clean. but cant say 1 was any worse. hard too say.
for got to mention timing chain was replaced about 10k ago, and thermo fan was left unplugged by mech and on way home she got a bit hot.
but still in tolarance. but when sitting still and restart, temp was off gauge.

but i like your answer antus. could be either way.

i have a used ecu comming from usa . dont know if works cost $66 all up. I want to see whats inside . wife wont let me touch ours yet lol.
just curious if i could swap and flashroms to new ecu if all parts same.

have an eprom progammer but dont know what in this 2011 ecu. could be something too modern
also dont know if each board has its one hardwired key end encryption. one would think it that is in memory writable and rom.
just trying too do it on the cheap lol. dont know what gear i need or how much too read old ecu data too new.

anyhow i just though maybe some ecu component maybe a bit flaky as considering age and heat and electronics its a wonderful combination for longevity lol.

I just wont too solve it cheap and simple.

I had my vt for 15years and spent maybe 3k at the most on it done 360k on the clock
had this ve 2011 for 18 months spent 4k and im just going what the hell!!! not going to let it beat be. fingers crossed

[HQ355]

Do yourself a favor and get tazzi's software and cable. You can then log it when it happens and go from there, also you'll then have it in the future if there's any other dramas

[amiga68000]

does his cable and software read the ve series 2 ecu 2011 up as they seem different and i thought even tech2 stuff needs updates. but i dont really know ?

[HQ355]

Sure does, I have a 2012 Calais and it reads it fine, easy to use and better than paying holden to scan it

[pman92]

If it's still P0301 and you have swapped cylinder 1 coil plug and injector it simply means it's not any of them causing it.
The misfire code is set by the ECU monitoring the crank angle sensor. It sees a misfire when the engine doesn't accelerate after it fires a coil. It knows what cylinder misfired by what coil it last fired.

So what else does that leave?

Either the code is wrong. The crank angle sensor signal or PCM is at fault. Logically this is highly unlikely. If it's doing it consistently and you can physically hear the engine misfiring you can eliminate this completely.

Or the code is right. If it's not coil plug or injector it can really only be a 2 other things:
-Something stopping opening the injector or firing the coil. PCM faulty injector or coil driver, loom shorted or broken or something. Very possible.
-Mechanical engine fault. If the misfire is all the time this can easily be proved with a compression test. If it's only occasionally then not so easy. Sticking valve? Carbon blocking a port?

I'm very interested to know the outcome of this.
My mum has a 2010 VE 3.0 that has misfired and brought the MIL lamp on twice in the 5 years she's had it since new. Both times it was P0300 misfire unknown cylinder. Both times it quickly fixed itself I think after she turned it off and restarted, and never played up again.

[amiga68000]

thanks guys for your input.
question if i had slightly low compression on c1 then one would think misfire would me more often and motor run rough right ?

i have not done compression test !
i have not tested for co2 etc in coolant. not loosing any or overheating etc.

it was also suggested too me that timing may still be an issue but i dont know enough. as engine is vvt quadcam one would think that one tooth out on timing would cause lot of havoc and show up in computer ? yes !
any how i have new and replacement ecu coming from USA .

will pull ecu apart when arrives.

I rang holden and asked how much to put new ecu in. 2011 3.6 sports wagon.

the first thing he said was are you suppling ecu !
cost for ecu clone was $450
did he say are you suppling because he knows there prices are a ripoff or because its common replacement ??????

[pman92]

If it's not all the time it won't be compression unless it was a sticking valve.

It don't believe it would be valve timing as that would throw a cam/crank position code, and would cause problems on all 3 cylinders of that bank.

If the new ECU doesn't fix it then I guess it's down to loom fault or mechanical fault (sticking valve).
Both sound pretty unlikely though.
I would go back over and recheck every thing though. Maybe swap the injectors around if it's not too hard, swap the coils and plugs around just to verify everything.