Vs has backfire and idle problems

[Jxfwsf]

I don't think i would've worried about a coil pack just yet, usually plugs, leads and a tune is all that most problematic. Atleast you now have a spare if you ever have problems with it
Code 35, i wouldn't be to concerned about that either atm, just means the ecu is having trouble controlling the engine idle, could all be to do with the out of tune lpg system.

I wouldn't mess around with unknown 2nd hand spark plugs (unless you have a sand blaster, small file and feeler gauges to clean and regap them)
a brand new set of standard plug should be between $24-$30....
2nd hand leads are a gamble also.... I pulled a set off a wreck once, they looked newish, on gas it idled fine and moved around the yard fine, free revved fine under no load... but when I put them on my daily driver as it was due for new leads it backfired and blew parts of the plastic intake to pieces upon hard acceleration from being stopped (they ran perfectly on petrol as well)
http://www.ebay.com.au/itm/DRIVE-FO...=AU_Car_Parts_Accessories&hash=item1c2d0c8486
for less than $50, 5 year/100,000km warranty it could be a worthwhile investment (same brand i have been running for the past 20,000 km's without an issue)
alternatively there are some cheaper options on ebay
http://www.ebay.com.au/itm/IGNITION...=AU_Car_Parts_Accessories&hash=item20c97a0f70
my pick if you get them in time for the sale would be the bosch ones
http://www.ebay.com.au/itm/Holden-N...=AU_Car_Parts_Accessories&hash=item2574fdbb0c


It's great that it's now running good on petrol, like most people that work on lpg will tell you "no point trying to tune an LPG system if it's not running on petrol correctly)
Another problem is that the ignition side of things may (plugs and leads) may run perfectly fine on petrol but will not on gas, before trying to tune it replace the plugs and leads.

Back yard tuning may suffice for some but in all honesty it's much quicker and easier to take it to an LPG specialist that can shove an air fuel ration sniffer up the exhaust and tune it within minutes.

If possible, can you remove your current spark plugs and take a pic or 2 of each one clearly showing the same area as the below pic (more light in the pic would be good).
Note what cylinder they came out of and name them respectively.
Looking from the front of the engine on the passenger side from front to back is 1, 3, 5
on the drivers side is, 2, 4, 6.

 

[Blackvs96]

For your reference (and ours) what you have, at least as far as I can tell from the pics., is an OMVL system. As a check, there should be cast into the part of the converter that faces towards the centre of the car "OMVL R90E". In any case, the metering of the LPG is done by that unit, although there may be some correction in between that and the mixer in addition.

v8Dualfuel.com: LPG / Autogas conversions and Kits for the Rover V8 Engine ???

boost reference help - fullBOOST ???

Those two adjustments on the converter are both for mixture control. The screw without the spring around it is for when the engine is at steady throttle or accelerating and the other one is "sensitivity". Sensitivity controls when the converter switches from an idle mixture on acceleration and back again on deceleration. You should have marked where the screws were before you started - paint or nail polish is good - so you can put them back to where you started from if it doesn't work.

This should help:

How To: How To Tune Your LPG system at home - www.fordmods.com

On a Commodore, don't bother with the feeler gauge but run the car on petrol and disconnect the Idle Air Control valve wiring connector then switch to gas. The IAC valve is the black cylinder on top of the inlet manifold. That does the same thing as using the feeler gauge; it stops the engine computer from altering the idle speed while you make the adjustments.

So you can understand what you are doing: Converter OMVL R90/E Parts under the Diaphragm

I'd be looking at the join between the mixer too (yes, you do have a mixer; that is what is known as a "simple mixer" - basically a tube with a smaller diameter restriction in it to draw the LPG into it) and the throttle body. All I can see that is forming the join is a wrap of electrical tape. Correct? If that join is leaking it will suck in air and cause a lean air:fuel mixture (low in fuel). That could be part of your problem.

There should be a very short length of rubber hose and a couple of hose clamps across that join. You may have to source the hose from an LPG workshop but you might try somewhere like Pirtek or Enzed if you explain that it has to be fuel resistant. It's possible that someone has left that hose off to avoid any damage if there is a backfire.

For reference:

http://www.fesautogas.co.uk/r90eservice.pdf (14Mb - you might not want to use a phone for this. It's a service manual for the R90E.)

Ok do i tried doing the home tuning on the gas and completely stuffed it so I'm going to wait till i get $90 and get the professionals to service it

 

[Blackvs96]

Ok I've managed to fix my car from running very bad and idling bad, what i did was opened the throttle body and cleaned the **** out of it, when i removed it, it was so dirty.

I also removed the plugs and since having no money at the moment i decided to clean it, sand it clean abit and re-gap it, till i get money to buy new plugs.

I changed the entire 3 coil pack including the bottom part of it i think its called dfi, put some newer 9mm leads, thank u to deer park wreckers giving it to me for free.

After all that the car runs so smooth on petrol and doesn't rumble rough forward when sitting at the lights.

So all that hard work paid off not sure what was the actual main prob but problem is gone now with running on petrol.

The only problem it's causing after the service is it now once in a while stalls when changing to reverse or to drive, it only happens sometimes, anyone know what they might could be? It doesn't loose idle before it stalls, it just stalls, w
hat could it be?

Btw i thank everyone a lot for all your help in trying to solve my car problem, with the gas problem ill just run it on petrol till i get the finance to get it to the gas
pro's.

Oh yh if it helps the ignition now cranks in one second, starts up very quick, I'm very happy bout that.

Anyways thank you again and looking forward to your always helpfull replys, don't know what everyone else would do if it was t for the development of this site.

TOP SITE #1

 

[Blackvs96]

I don't think i would've worried about a coil pack just yet, usually plugs, leads and a tune is all that most problematic. Atleast you now have a spare if you ever have problems with it
Code 35, i wouldn't be to concerned about that either atm, just means the ecu is having trouble controlling the engine idle, could all be to do with the out of tune lpg system.

I wouldn't mess around with unknown 2nd hand spark plugs (unless you have a sand blaster, small file and feeler gauges to clean and regap them)
a brand new set of standard plug should be between $24-$30....
2nd hand leads are a gamble also.... I pulled a set off a wreck once, they looked newish, on gas it idled fine and moved around the yard fine, free revved fine under no load... but when I put them on my daily driver as it was due for new leads it backfired and blew parts of the plastic intake to pieces upon hard acceleration from being stopped (they ran perfectly on petrol as well)
DRIVE FORCE IGNITION LEADS - HOLDEN COMMODORE VS & VT SER'1 3.8LTR 1995-6/99 | eBay
for less than $50, 5 year/100,000km warranty it could be a worthwhile investment (same brand i have been running for the past 20,000 km's without an issue)
alternatively there are some cheaper options on ebay
IGNITION LEADS HOLDEN COMMODORE VN 11/91-VP,VR,VS,VT,HEAT SHIELDED HANSA BRAND | eBay
my pick if you get them in time for the sale would be the bosch ones
Holden NOS Commodore VS BOSCH Super Sports Ignition Leads B6121i | eBay


It's great that it's now running good on petrol, like most people that work on lpg will tell you "no point trying to tune an LPG system if it's not running on petrol correctly)
Another problem is that the ignition side of things may (plugs and leads) may run perfectly fine on petrol but will not on gas, before trying to tune it replace the plugs and leads.

Back yard tuning may suffice for some but in all honesty it's much quicker and easier to take it to an LPG specialist that can shove an air fuel ration sniffer up the exhaust and tune it within minutes.

If possible, can you remove your current spark plugs and take a pic or 2 of each one clearly showing the same area as the below pic (more light in the pic would be good).
Note what cylinder they came out of and name them respectively.
Looking from the front of the engine on the passenger side from front to back is 1, 3, 5
on the drivers side is, 2, 4, 6.

View attachment 158744

My plugs looked similar to that, as dirty as that,

 

[Jxfwsf]

great to hear it's running better now, there's nothing wrong with cleaning plugs with good old sand paper or an emery board (used to be common practice to use a small sandblaster to do the same job, quicker but just as effective)
only real problem is when the electrodes (2 points that the spark jumps across) get burnt out from the high voltage spark, given labor costs it's generally cheaper to replace than spend the time cleaning, filing and re-gapping.

regarding the pic above, the main thing I was looking for was if any of yours looked different to the rest, whiter, browner, blacker than the others, just to see if there was another underlying issue

now the new issue with random stalling... time to do another fault code check (and hope an error has been logged)..... if it's all running better with the leads and plug cleaning then I may be suspecting the replacement DFI module..... sometimes it's better to change 1 thing at a time than change many things, as you've found out.... change a few things at once and now you're wondering what made it better and what's made it worse.

 

[Blackvs96]

I changed the dfi with the coil pack but still stalls, my guess is something around the air intake but who knows. Gotta says since all the replacements the engine idles so smooth on petrol that it sits on 900 at the lights and the pin doesn't move.

Think I need new break booster cos the break pedal is hissing real bad tryed bleeding still doesn't go away just hope its not hard changing it.

Can a v8 booster fit into v6? Does it make any better breaking differents?