Technical Thinking caps please: Injector Leak off test

[theoneandonly]

i Recently seen a video where the efficacy of a injector cleaner was tested by doing a leak off test before and after doseing with cleaner. How realistic is it to use a leak off test in this way? I have used a scan tool and monitored injector vanriances before and after cleaning. This was very sucessful with a 80000 mile VW engine but no differences with a 10,000mile Ducato. Any other tests offered, specificaly for post combustion areas that certain additives are suposed to clean.

 

[bugsymike]

i Recently seen a video where the efficacy of a injector cleaner was tested by doing a leak off test before and after doseing with cleaner. How realistic is it to use a leak off test in this way? I have used a scan tool and monitored injector vanriances before and after cleaning. This was very sucessful with a 80000 mile VW engine but no differences with a 10,000mile Ducato. Any other tests offered, specificaly for post combustion areas that certain additives are suposed to clean.

To be honest I am always a little sceptical about additive treatments, although have seen results with DPF fuel additive, but may have been related to the 30 mile run in 4th gear at 2500 rpm.
I suppose if leak off test accurately measured at exact same revs, temp. and time span, but only a guide.

 

[puntodad19]

Cleaning....self decoke....honda cb125s....1976, that long hot summer, remember them ?

10am start from West Cornwall...tinturn hill headlight blew...turn left at chuck chicken heading to welshpool....hot evening, standing crops tinder dry in fields....kept thinking car was behind me....looked round, saw millions of sparks coming from exhaust pipe end, looked down, saw exhaust pipe from cylinder head into silencer glowing yellow hot...engine running well, go to town half hour before pub closed, 10:30....first pint was just poured down throat....true story.....leaded petrol in them days....

 

[bugsymike]

Cleaning....self decoke....honda cb125s....1976, that long hot summer, remember them ?

10am start from West Cornwall...tinturn hill headlight blew...turn left at chuck chicken heading to welshpool....hot evening, standing crops tinder dry in fields....kept thinking car was behind me....looked round, saw millions of sparks coming from exhaust pipe end, looked down, saw exhaust pipe from cylinder head into silencer glowing yellow hot...engine running well, go to town half hour before pub closed, 10:30....first pint was just poured down throat....true story.....leaded petrol in them days....

Was that when you realised you had been in third gear most of the way with engine screaming it t*ts off.
I recall the hot Summers, Saturdays would be lunch time drinking at local , followed by walk through town to buy bottles of "natch" cider, then down to the beach swimming and playing football with a "borrowed" ball but being beaten by it's owner as so legless.
Shortly after that buying first house and have been poor ever since.

 

[AnthonyH]

My feeling is that additives make little or no difference.

I once looked up a scientific report which tested them thoroughly and it said they work. But i'm sceptical, i'm more inclined to think the additive manufactuers paid the scientists.

I tried them and it made no difference, apart from an engine management light.

 

[theoneandonly]

My feeling is that additives make little or no difference.

I once looked up a scientific report which tested them thoroughly and it said they work. But i'm sceptical, i'm more inclined to think the additive manufacturers paid the scientists.

I tried them and it made no difference, apart from an engine management light.

So what test methodology did you apply to your rigourous scientific test. If none how do you know they made no difference. I have a desire to test not assume.

 

[AnthonyH]

So what test methodology did you apply to your rigourous scientific test. If none how do you know they made no difference. I have a desire to test not assume.

Enjoy your testing.

 

[bugsymike]

My only simple test in that direction was around 1970 when STP was giving out free samples of their product along with claims it would increase oil pressure and reduce friction, the vehicle I used had a brand new Smiths rev counter and oil pressure gauge, after using their product and watching carefully I saw no perceivable difference in those readings. From their claims I would have thought a slight oil pressure increase and a few revs more as not ECU controlled would have validated what they had said.
I do appreciate this is hardly a scientific analysis.
Some years later working as foreman of a dealership the company introduced an insurance based warranty on used cars that involved oil changes using a tin of their additive, we used the product religiously with no noticeable effect apart from the fact that the small print on the warranty meant unless you were unfortunate enough to see a con rod burst out the side of the engine , everything else was declared "fair wear and tear" and not within their terms of warranty which did nothing for customer satisfaction, apart from confirming my thoughts about Insurance based warranties.