Gas good but not running on petrol

[dellarb]

Hi all

Ok so my VS had a dual fuel setup installed a year or so ago and recently it no longer runs on petrol. I have to manually set it to gas each time and it does start and runs normally on gas once it's going. If I try to switch to petrol while running it coughs a few times then dies.

Now a while ago it had a backfire, thought nothing of it however I discovered after a few days driving it had actually blown out half the air box meaning it was inhaling unfiltered air (sounded and ran normally at the time). Air box and filter replaced now of course.

My random guess might be that the fuel injectors are clogged? Can anyone who knows these things better confirm or deny what might be causing it?

Cheers

[Farax]

hey i had a similar problem with my vy, i simply changed the injectors and the coil pack, gave it a nice rev and it was all good

[HamaTime™]

Yeah, try replacing your injectors, maybe coil pack as well...also check your MAF (Mass Airflow Meter) - which can be blown by backfiring.

With a dual fuel car, if you run primarily on gas, make sure you run petrol at least once every 2 weeks, for at least 15 k's including a good rev to clean injectors and to keep the petrol system fresh.

I run 2 tanks of gas to $20 of 95 or 98 Petrol...

[Brett_jjj]

If a gas/petrol vehicle is not run on petrol for a few minutes every couple of weeks the fuel pump can seize up through lack of use.Sometimes a good bang on the bottom of the fuel tank with a rubber mallet will fix em up and get it running again.Have seen this a few times before on duel fuel cars where gas has mainly been used and they havent switched to petrol regularly.When running on petrol you should be able to hear the fuel pump running,with the engine idling if you get under the rear of the car and get your head near the fuel tank and you should be easily able to hear the hummimg sound of the fuel pump running.Get someone to switch over the fuel and listen for the pump to run from the back of the car.Make sure the fuel filter is replaced often because they dry out when not being used (when running on gas)and when they dry out crud and scum develops in them.Ive cut a fair few old fuel filters in half and you should see what is in some of them.It makes you wonder how stuff like that can get into a fuel tank and even more unreal is how it gets through the pump and its strainer etc.You should use the fuel in the tank every few weeks,otherwise it goes stale which will make the car run crappy when switched to petrol.And driving around town with the petrol tank full just wastes fuel because of the extra weight.Around a quarter of a tank is fine to keep it at.

[sik_dose]

How much do you save per tank using gas?

[westbad]

when you turn your accessories on can you hear the fuel pump prime??

[dellarb]

Thanks for the responses. Now you mention it I can never hear the fuel pump priming (even when it did work) will get a mate to help me out and ill stick my head under to listen. Otherwise it looks like new injectors/clean injectors etc.

sik_dose: I have a wagon with the 55L donut tank so 1 tank doesnt equal 1 tank but usually a fill up of 50L gas gets me about 300km of almost all city driving. 17L/100km it works out at usually

[executer]

spark plugs and leads mate. the exact same thing happened to my vs. im running duel fuel also. just had them replaced last week, no problems at all.

[executer]

by the way, i also go t anew fuel pump as mine also shit itself, at 235,000kms

[LeeoD]

Fuel pump.

[strgas]

be sure the fuel pump hasn't been turned off when running on gas this can over heat the injectors when running with out petrol in the rail to remove excessive heat , fuel in the tank is good for about 3-4 months using petrol regularly is best advice aleast 30 liters a month is recommended , regular filter changes as per service recommendations .