VT 3.8 slight miss

[GMDriver]

Hi all.
Straight to the point.
The wifey's VT has been playing up at idle, sometimes stalling. 230,000 km's has LPG/petrol
Replaced plugs & Leads, but didn't seem to help much so after some reading on here decided the symptoms were Vac related.
Purge hose is fine & decided to replace the inlet manifold gaskets (which were stuffed), glad I did that.
Ok, so now idle's much better but still has a slight miss at idle & lower revs & has no Vac leaks
Purchased ALDL cable & have tunepro, also EFILIVE, not getting any fault codes which i was hoping for to point me in the right direction.
Coils seem to arc to each other with strong spark with the leads off, coil at a time, so I don't think it's them.
It's also not a petrol system/injector issue as it does the same on LPG. pulled the plugs looking for cracks but all is well
I believe it to be electrical but there is no braking down/missing under load, it runs like a clock on both fuels, just this pesky miss down low/idle
Any idea's
Thanks

 

[The1]

post a tunerpro log up, o2 sensors might be on the way out.

 

[GMDriver]

post a tunerpro log up, o2 sensors might be on the way out.

Site wont let me attach XDL files???

anyhow, 2 new Genuine Walker o2 sensors on the way, time to replace the old one's which i suspect are the original ones,
O2 readings both sides give similar readings until the engine starts to warm, and then one side readings starts to differ a great deal from the other
this is when the rough idle starts...

 

[GMDriver]

well, more $$ spent
2 new O2 sensors & still the same:bang:

 

[Lex]

Have you reset PCM?

 

[GMDriver]

yes, reset

 

[GMDriver]

Cleaned/sanded the earth terminals
2 on the drivers side guard & 1 below the alternator.
idles much better, im guessing the earth for the o2 sensors was bad

 

[azzaVT]

Update please...

G'day GMDriver,

I'm keen to hear if this was the fix for your troubles; I've got similar going on with an almost identical car.

Cheers,
AzzA

PS sorry to anyone sensitive to old posts being resurrected... but some of us are driving the "walking Dead".

Cleaned/sanded the earth terminals
2 on the drivers side guard & 1 below the alternator.
idles much better, im guessing the earth for the o2 sensors was bad

 

[VTS5]

Don't you hate them? You wont hear a thing from the buggers 'till something else folds.They only come here to cry.

 

[GMDriver]

Don't you hate them? You wont hear a thing from the buggers 'till something else folds.They only come here to cry.

My last post 6.12.13,
azaVT asks 10.11.14, nearly a yr later...... Plus I wasn't exactly getting a mountain of responses...