I concur always a Y not a T.
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I concur always a Y not a T.
1-Confirm fuel pressureQuote:
Originally Posted by Pezzer
2-confirm fuel supply rate of flow
Does it start better if you prime the High pressure pump by cycling the reds on and off 3 or so times?
Does it start better when warm?
When warm no problem.
Pezzer said that the miss goes away with higher revs. Would a fuel supply or pressure issue do this or would it get worse the higher the revs?Quote:
Originally Posted by davo94
How old are the plugs pezzer?
Not sure on the plugs, but we have done 3000kms on them, I reckon on around 5000kms
Depends if they run a dual speed fuel controler. You could also try and crimp the return line to run full line pressure and isolate the pressure reg (just for testing)Quote:
Originally Posted by taslucas
Is this what pezzer has done below?Quote:
Originally Posted by davo94
Quote:
Originally Posted by Pezzer
Seems he has.Quote:
Originally Posted by taslucas
Get a compression test to rule out the mechanical aspect then we can isolate it to the ignition system.
yes I crimped the return line and also removed the vacuum line to the regulator, no noticeable difference.
What brand of plugs and gap are you running.
Lpg likes a smaller gap around .2 less.
and more advance on the timing 12-15 deg not 10 as per petrol specs.
go to advanced and petrol runs out of puff at a much lower speed and ping/det becomes a problem.
My experience found NGK iridium plugs work better and last longer.
Design is a much finer electrode to concentrate the spark,
also helps expose the spark better to the mixture, m2c.
but 3 x times the price.
Have read some where, maybe this forum.
LPG = NGK plugs, more reliable.
quality or something
I'm sold on em.
Okay still with Gasman, so far changed all plugs, found a broken hose after the air flow sensor and replaced cleaned Maf sensor got a rise in revs straight away. So now we have an engine running rich that the computer believes is lean.
Latest update loose fitting injector plugs.
Injector plugs sorted still a dam miss on both LPG AND PETROL replacing leads, fingers crossed.
Disconnect your Battery for an hour to reset your ECUQuote:
Originally Posted by Pezzer
a stuffed O2 sensor can rich-en an engine.
humm dosent explain lpg does it !
the sensor was stuffed but replaced so all petrol probs have gone, just a miss on both fuels. To top that my Rodeo has done an alternator so I cannot go to the workshop to check whats going on.
So It must be electrical then.
And this problem is not unique to just efi either, carby can do the same.
so you may rule out dizzy but the cap still suspect! ,
read here only use gen caps, less troubles.
Okay took it for a run today hard to start first up, and was shuddering I then went onto the Hway and it started missing then started pinging (only drove on petrol). The Lpg guy has a concern that the oxygen sensor location in the extractors only collects from the front 3 exhausts and not all 6.
Sorry forgot to add, whilst on the highway when coming off the throttle and going back on it, the drive take up was quite aggressive.
Pull the dissy cap off, pull the rotor off and there's a cover with a couple of screws on it. Underneath it is a thin disk with 360 notches in it. Make sure this disk is immaculate. If there's traces of dirt or water you might have to pull the entire contents out and clean the optical pickup sensor.
okay Parksy will check it out.
Feel for ya Bro,
there is nothing more frustrating, when this then that with little result.
and a truck load of $$.
seems it's not your problem , maybe worth a mention anyway, ya never know !.
My sons GQ tb ,also lpg, has a Genuine Nissan dizzy cap and it runs as smooth as a baby's bum,
people have commented how well it runs and starts.
tuned by me 12 mths ago, and I ask regularly how it's going, "still good" .
there maybe something to Gen product ver's aftermarket.
Ver's Mine has a slightest of miss,cant seem to tune out.
might talk him into swapping parts to compare.
will post up results afterwards.
Hope ya get it sorted soon.
Yes its a bitch as its stopping us from using the boat in this great weather.
Have had a set of the top dollar bosch lpg compatable ign leads fail within about a year.
running coil wound at the moment seem ok
Just a thought - in let manifold gasket leak similar to this thread
TB42 running on 4 cylinders?
I thought the same thing too but pezzer has only just recently swapped from a carby setup to an efi setup.Quote:
Originally Posted by GQ TANK
Yes definitely no leaks, still have original dizzy cap and rotor button.
also had same thought, I also have new gaskets, and a slight miss and guess/ruled it out.Quote:
Originally Posted by GQ TANK
G,day, I gota 4.5 EFI petrol.
Had a miss at idle even after service, plugs, leads etc.
Got my tappets adjusted next major logbook service.
Rough idle/miss is gone?
Worked for mine, Maybe try that??
Daz
The coil is being checked over at the moment so hopefully waiting for a call.
I have pulled the Maverick from the Gas shop and am now having our mechanic check it over as now its quite bad missing across a few cylinders and stalled 2 times whilst pulling away on a hill.
No leaks
new leads
new plugs
new oxy sensor
cleaned Map sensor
cleaned in dizzy under plate
cleaned rotor button
cleaned dizzy cap
Timing set 10 degrees
Fuel injector plugs all checked and refitted securely.
What was the compression reading on all cylinders? Another component that is common to both fuels is the changeover switch. Check that the wiring and connectors are crimped tight. You could bypass it to eliminate that the internal contacts aren't loose.
Ignition died found the coil to be the culprit, fitted new coil and started straight away still missing and hunting at idle on both fuels.
compressions all around 150. dual fuel switching all good.
Clutching at straws now, but, next component common to both fuels is the carby. Running gas, can dry out the seals and such inside it and cause trouble can't it?
It is fuel injected.
Yeah, I forgot. sorry. Haa ha. Its such a common problem with gas. Thinking cap back on... You've cleaned the dissy. Are to able to swap it with someone elses, just to eliminate it entirely? As years ago my falcon had an intermittent miss, and I found it had tracked a long some almost invisible fine cracks.
Done that no difference.
I am out of Ideas, sorry, Pezzer. I have owned two efi vehicles, and they either ran really well, or not at all.
Did you replace the collector gasket when you had it all apart? Ie split the big intake plenum apart and replace the gasket? Is it possible you've hooked the vacuum lines up incorrectly? Does the air regulator on the bottom of the plenum appear to have any leaks? Have you cleaned the aac valve assembly on the back of the plenum?