LPG backfire issue

[frogsta]

When mine backfired I had a pod as well, just thought I'd let you know

 

[DVS_DANNY]

Hi, Same Issue i suspect, how hard is it to tune the lpg? i have a little Gastec fuel processor with led gauge mounted to the passenger side strut housing near the airbox which appears to have two adjustment interfaces , i didnt know all this, i just started repairing what i thought was a busted airbox-intake to manifold flexi thing. any help appreciated

 

[DVS_DANNY]

After a bit of stuffing round, i refitted 8mm spark plug leads and cleaned, and gapped my sparkplugs, check repaired or replaced any air hose leaks, increased the mix ratio a little and make sure i don't try to overtake a caravan in 5th uphill at 95kph, chop it down a gear!

 

[Vince89]

Back fire with gas

Hey i started my car on LPG by mistake today and it backfired, running on petrol it was nearly stalling and running very rough, i got it home, checked the MAF and vacuume lines, MAF is fine, only problem i found is the vacuume line under my throttle body was disconnected. Since reconnecting it, it runs on petrol, a little rough, but every time i switch it to LPG the revs drop and the car stalls, what could it be as i dont trust big name mechanics. Cheers

My VR would back fire at random times and only stop after running on petrol for a couple days then back fire again.

first I adjusted the gas- maybe too lean - no not that

changed spark plugs and leads - after 3 months back fired again etc - changed spark plugs again - after 2 months back fired again- no not that then.

adjusted the gas to be a little richer- only a touch - OK for a while, back fired again- no not that

heard a noise one day coming from the back of the car- a friend told me it was the petrol pump.
So I added a treatment for the petrol pump and that also cleaned the injectors
after a couple of weeks the noise stopped.

NOTICED THAT CAR WASN'T BACK FIRING!!!???

conclusion the injectors needed cleaning!!!

it has now been 8 months on the same spark plugs and leads --trying to get to one year maybe I will change the spark plugs then but manual says 2 years.
I will wait and see
so far so good no back fires. LOL

UP DATE ------ its been over a year and the car would stall when driving so I changed the spark plugs.
Conclusion THE PETROL TREATMENT DID IT cleaning the injectors- PS my car doesn't have a carburettor- if you do you need the lead replacement oil that drips into the fuel/air flow- ask the guy that fitted the LPG.

UP DATE ---- - my car started to BACK-FIRE ETC AGAIN. PUT SOME MORE petrol treatment- stopped for about 3weeks.

One day it didn't have the same pick up etc. It stalled and no start on gas or petrol.

RAA man said it was the CRANKSHAFT POSITION SENSOR. Have a look in the manual, the sensor is just behind the crankshaft balancer

HE said the sensor can become faulty and hot. He poured water over it to cool it and the car started again and ran normally.

A mechanic replaced the sensor for $160 and now the car hasn't MISSED ON GAS SINCE. It has been well over a year!
Perhaps one only needs to pour water onto this sensor to see if the BACK-FIRES, stalls, rough idle etc stops for a couple of kms etc

The crankshaft position sensor may need replacing?!

good luck

 

[tk55]

hmm...i always had the idea that lpg doesn't use the fuel injectors? maybe i'm wrong.....

 

[EYY]

Lpg has nothing to do with the petrol injectors

 

[Vince89]

go to this site
What is a fuel injector? How do you clean fuel injectors?

 

[CCCMikey]

I must be lucky!

I've done at least 100,000km on the current plugs and leads on LPG, and it's never backfired yet. LPG conversion in 2008.

 

[pramodsoni41]

Hi,
I recently bought Ford Ikon 1.3, with LPG fitted. I am having issue of backfire sometimes. Especially when the engine is not heated. After few kms backfires are gone. I get backfire only when I am running on LPG, however on petrol, I don't get any backfires. I checked the car with mechanic, and he says, the ignition coil may be the problem, but he is not sure. Initially the backfire problem was not, but it started after few hundred kms. My question is should I change the ignition coils?

Ignition coil is slightly broken at one of the spark plugs.


Or could the reason be LPG gas?

 

[Vince89]

please refer to update above BACK FIRE ON GAS
I found why my Commodore kept backfiring at random.
vince89