Would leaking injectors cause a miss? (Holden VS)

[James39]

Not sure what is going on with this. I just got this car the other day and it was running well, but it ran out of fuel, so I topped it up and was fine for a while until it started to run rough and miss.

When I was checking the plugs I found that the front two passenger side plugs where wet with fuel. The miss seems to alternate between these two cylinders as well.

Would replacing these two injectors fix the miss it has, or would it need a inlet manifold gasket or maybe a head gasket?

[Brett_jjj]

It could be that the ignition coils or DFI module is faulty.Is the sparkplugs in these cylinders firing? Id check these first because if the plugs are wet with fuel,that shows that theres no spark to fire the fuel injected into these two cylinders.

[James39]

There seems to be plenty of spark... I tested the coils I have from my VR and there was no change. The DFI setup from the VR does not seem to fit the VS either? So I could not test the DFI.
However when I was messing around with the plug on the DFI yesterday it ran normal, but I was worried about the connection as I heard a crack noise when I tighten the bolt so I undone the plug again.
Now the miss is back and it seems to alternate the miss between the two cylinders.

The wet plugs were like that long after the car had been stopped, as I went to buy new spark plugs. Plus when I removed the plug some fuel dribbled out of the hole.
Also I noticed there is oil on the top of the inlet manifold, which makes me think there is a leak there.

I keep thinking that I may have a blown head gasket...

[Brett_jjj]

Id get hold of another good set of known working injectors ,and fit them, or at least remove the old ones and test them for leaking, as they could be leaking fuel into the cylinder(s).Id also get a compression test done on the engine,and Id also get the cooling system pressure tested as well.And Id get the hot and cold oil pressures tested while they are at it.This will give you an overall idea on the condition of the engine,and whether its worth spending money on..These tests shouldnt cost a real lot to get done.It beats throwing away money on an engine thats past its use by date..
Ive just fitted these brand new injectors in the link below to my VSV6, and they are running excellent so far,Im very happy with how they perform.It was nearly gonna cost me just as much to get my old injectors cleaned and reconditioned etc,so these are well worth it I reckon.

---http://www.ebay.com.au/itm/HOLDEN-CO...item2c5d8a0161---

[moggy]

Why don't you try moving the two suspect injectors to the other side and see if you end up with wet plugs there?

[James39]

Thanks for the advice Brett and the link... New injectors were on my list to buy among other things lol

Could ####ed up injectors cause the miss it has though? Due to giving it too much fuel?
Before I got it, it had always had cheap fuel and now since I have used V-Power this problem has occurred.
It is the strange though because on the day it started to miss it would clear up and run normal then start to miss again at random.

Are there any tell-tale signs that I can check on the DFI? As I am going to remove it tomorrow.

Sorry for asking these things, but I am still learning about these cars lol

Why don't you try moving the two suspect injectors to the other side and see if you end up with wet plugs there?

I have not got that far yet

[James39]

Ive just fitted these brand new injectors in the link below to my VSV6, and they are running excellent so far,Im very happy with how they perform.It was nearly gonna cost me just as much to get my old injectors cleaned and reconditioned etc,so these are well worth it I reckon.

---HOLDEN COMMODORE NEW FUEL INJECTORS VN VP VR VS VT VX + | eBay---

Do those injectors come with new seals (o-rings)?

[Brett_jjj]

Do those injectors come with new seals (o-rings)?

Yes they come with new o rings fitted,they are ready to install.You just need to put some clean engine oil or petrolium jelly onto the O rings before you install the injectors.They took 2 days to get to me by post which I was also happy with..

[James39]

Thanks again Brett.


It sure does seem to be the injectors because they seem to stop working (The ticking noise stops). I was going to pull it apart but decided not to until I had the new injectors plus when I am ready to give the throttle body and plenum chamber a clean... I have already cleaned out the IAC....


I just hope there is not crap in the fuel lines... If so, is there a way to clean out the fuel lines?

[Pickle']

Why dont you do what Moggy said, Its not hard to do will take you 20 minutes maybe tops to do, Just change them around atleast you'll know thats what wrong with it before spending money.

[James39]

Why dont you do what Moggy said, Its not hard to do will take you 20 minutes maybe tops to do, Just change them around atleast you'll know thats what wrong with it before spending money.

I failed to mention this, but I tested the connections to those injectors and there was a pulse (with a light tester). This should be enough to indicate that it is working on those connections??

[BlackVXGTS]

If the problem started just after you ran out of fuel, I'd be suspecting that you have sucked in some contamination (eg. water, dirt) from the fuel tank into the fuel lines. First thing to do would be to replace the fuel filter and pour about 500ml of methylated spirits into the fuel tank and see how things go from there. Some injector cleaner could also help if that doesn't work.

[James39]

I agree, it was only like in the first 10 mins after adding more fuel (Put in about $30 worth) I supected that the injectors were clogged up due to crap in the tank, did not think water would be in there.
Anyway this week I will be getting a new fuel filter among many other things and even try the metho I will get some injector cleaner as well.

[James39]

Ok I have replaced the fuel filter and added some Metho lol... it now seems to be much worse... It seems to have plenty of revs without moving all that much and now seems to miss on two cylinders. I am now stumped...

[Brett_jjj]

Id just replace the injectors with the new ones in the above link if yours are more than a few years old.Id replace the fuel filter as they are only cheap anyway,Id also blow the fuel lines out with compressed air,and Id check the fuel pump pickup strainer in the fuel tank to make sure its not blocked up with rubbish,and also check the bottom of the tank itself for dirt etc whilst the fuel pump is out of the tank..You could just get the fuel pressure tested which should show up any problems with the fuel systems.
I always replace my fuel filter every 5000 km or every oil and oil filter change.With fuel filters being so cheap to buy,and easy to replace,why wouldnt you replace them heaps often..

[Cheap6]

I'm not sure that it will fix any problem but I think that it's worth commenting that rather than add methylated spirits - which is not guaranteed to be free from water - in a low concentration, in an effort to remove any water from the fuel tank, it's better to run a tank (or two) of E10 though the system.

E10 is (almost) guaranteed to be free from water and ~60l of E10 will have (up to) 6l of the ethanol that co-dissolves the water and HC fuel components.

Adding E10 is also cheaper and easier.

[James39]

Id just replace the injectors with the new ones in the above link if yours are more than a few years old.Id replace the fuel filter as they are only cheap anyway,Id also blow the fuel lines out with compressed air,and Id check the fuel pump pickup strainer in the fuel tank to make sure its not blocked up with rubbish,and also check the bottom of the tank itself for dirt etc whilst the fuel pump is out of the tank..You could just get the fuel pressure tested which should show up any problems with the fuel systems.
I always replace my fuel filter every 5000 km or every oil and oil filter change.With fuel filters being so cheap to buy,and easy to replace,why wouldnt you replace them heaps often..

I agree Brett, I feel these injectors could be the original ones from factory lol I replaced the fuel filter yesterday and after that I added a $25 fuel system cleaner (Not sure I can say product name here) which seems to have improved things. It now idles much better but still misses under load.

So I am going to replace the injectors very soon, plus the oxygen sensors, not sure what else at this stage...

[James39]

I'm not sure that it will fix any problem but I think that it's worth commenting that rather than add methylated spirits - which is not guaranteed to be free from water - in a low concentration, in an effort to remove any water from the fuel tank, it's better to run a tank (or two) of E10 though the system.

E10 is (almost) guaranteed to be free from water and ~60l of E10 will have (up to) 6l of the ethanol that co-dissolves the water and HC fuel components.

Adding E10 is also cheaper and easier.

Heard bad things about E10 so I avoid it...

[Cheap6]

Heard bad things about E10 so I avoid it...

But you are fine with adding metho? (Post #14).

My point is that if you are going to add ethanol (i.e. methylated spirits = ethanol + water? + denaturing substance) you would be better to do it using the E10 instead.

I think that you will find that Shell V-Power also has 5% ethanol in it and you are apparently fine with using that.

I note that you only noticed a problem after using the V-Power (Post #6). Ethanol can lift some types of residue from inside the fuel system. It depends where it's from and where it ends up but this may be why you now have the problem.

It's only a one off thing so once any residue is removed - by changing fuel filter, maybe flush injectors etc. - it won't re-occur.

[Brett_jjj]

The metho allows small amounts of water in the fuel tank to mix in with the fuel so it can be pumped through the fuel filter,through to the engine, and burnt off in the combustion process,so any water thats already mixed with the metho before you put it in the fuel tank, will just mix straight in with the fuel and will be burned off anyway..The metho trick has been used for years.I can remember old blokes talking about it when I was a young bloke many moons ago.

[ephect]

Why don't you try moving the two suspect injectors to the other side and see if you end up with wet plugs there?

I failed to mention this, but I tested the connections to those injectors and there was a pulse (with a light tester). This should be enough to indicate that it is working on those connections??

What moggy is getting at, has nothing to do with pulse, if its the actual injector leaking, when the cars off there is no pulse. Swap the 2 suspect injectors to the other side run it for 5-10mins, wait another 5-10mins check to see if the plugs are wet.

this would have cost you nothing and would have pin pointed exactly injector or not.

[James39]

But you are fine with adding metho? (Post #14).

My point is that if you are going to add ethanol (i.e. methylated spirits = ethanol + water? + denaturing substance) you would be better to do it using the E10 instead.

I think that you will find that Shell V-Power also has 5% ethanol in it and you are apparently fine with using that.

I note that you only noticed a problem after using the V-Power (Post #6). Ethanol can lift some types of residue from inside the fuel system. It depends where it's from and where it ends up but this may be why you now have the problem.

It's only a one off thing so once any residue is removed - by changing fuel filter, maybe flush injectors etc. - it won't re-occur.

I only added Metho as I had nothing to loose as it was running like crap, it seems adding the Metho made it run much worse..

I have used V-power for many years now and never had any problems in any other car. The problem occurred because I ran the tank dry (Which is not a good thing for the pump) I have no doubt there.

What moggy is getting at, has nothing to do with pulse, if its the actual injector leaking, when the cars off there is no pulse. Swap the 2 suspect injectors to the other side run it for 5-10mins, wait another 5-10mins check to see if the plugs are wet.

this would have cost you nothing and would have pin pointed exactly injector or not.

Done that today and there is two injectors that leak…….

[ephect]

so the wet plugs followed the injectors, awesome! when you receive the injectors, you should be sweet!

[James39]

so the wet plugs followed the injectors, awesome! when you receive the injectors, you should be sweet!

For that part of things yes

Thanks for all the advise guys

[Cheap6]

The metho allows small amounts of water in the fuel tank to mix in with the fuel so it can be pumped through the fuel filter,through to the engine, and burnt off in the combustion process,so any water thats already mixed with the metho before you put it in the fuel tank, will just mix straight in with the fuel and will be burned off anyway..The metho trick has been used for years.I can remember old blokes talking about it when I was a young bloke many moons ago.

No dispute with that. What I am saying is that using E10 is a better way of adding the ethanol.

Add metho to tank = petrol + ethanol (+ denaturant + (possibly) extra water) @ ~$5.00/l for the ethanol.

E10 fill = petrol + ethanol @ ~$1.00/l for ethanol + it's easy.