Wynn's Diesel Injector cleaner

[deian]

Is this recommended? My dad advises not to use it because I have a catalytic converter on my car. I think it'll do more good than bad. Any advice, thanks.

[Ian Fearn]

Having used veggie oil quite a bit in my last car it began to struggle with cold starting.

I reverted to diesel and still had problems.

I put a bottle of STP injector cleaner through them which cleared the problem after about 200 miles.

If your concerned about the condition of your injectors then i'd be tempted to whip them out and give them a clean.

All this ultrasonic stuff seems a bit pricey to me when you consider that you can actually BUY an ultrasonic bath for about 30quid.

[deian]

not too concerned, lets call it preventative maintenance, so i don't have to take them out to clean them, so you'd say it's good stuff, it works, but what about the catalytic converter?

[dnsey]

Good point about the cat, but surely it would say on the bottle if there was any risk?

[deian]

exactly, so i'm looking for evidence here, anyone got any experiences? Please? pretty please?

[AndersDK]

Just finished a tankfull added 1 bottle of the Valvoline "Diesel fuel treatment" stuff. In my case it seemed to work miracles. I've noticed 2 things :

1) Increasingly calm & silent engine running during drive
2) Amazing increase of mpg. From 700km to 900km on a tankfull - over the same route using the same mixed driving pattern - not been keen to lift off the foot.

Please note that this is on a 1.7TD with 425Kkm on the clock. Others have experienced that bad mpg went back on the engine shortly after. If that is the case on my engine too - its injector cleaning or replacing planned.

Anyway its a cheap try - some £3-5 a bottle.
Son-in-law is running Redex diesel additive in his diesel right now, as he's got a nasty black smoke problem on his 1.9D.

[BonceChops]

with an mpg increase like that it is almost worth adding it every time

[alan s]

with an mpg increase like that it is almost worth adding it every time

Unfortunately Neil, it doesn't work like that. It's like if you take all the things that claim to save you 10% of your fuel consumption; if you use 11 of them, then does the tank overflow?
If the injectors were badly carboned and this stuff washed it off, the consumption may improve from say 40mpg to 50 and will stay at that figure possibly until they begin to again get covered in carbon.
We had a petrol TZi that was an oil burner due to it only having done very low miles and we suspected glazed bore or sticky rings. It was suggested we put brake fluid down the plug holes and leave overnight. The effect on performance was outstanding as I would say it gained at least 10% in performance. A while later I had to remove the injectors to fit new seals and discovered the holes they fit in almost filled with carbon. I manually cleared them out, but whilst the initial clean out with the brake fluid made a big difference, the final total delousing of the area made absolutely no difference at all to performance.
Moral of the story is, that the brake fluid washed the garbage off the critical area so the residue was just there for the ride, however in the long term, whilst the fluid clean off would have regrown within a short space of time, the manual clean should last many times longer, so it's really more a case of routine maintenance than long term solution when used.
FWIW, when I was in my trade, refrigeration, many years ago, it was common practice to use methanol in systems that had moisture in them as it dissolves moisture and lowers its freezing point. You'll find most injector cleaners have that as a major component of their recipes in many cases the only one, but often shown on the bottle but called a corporate copyrighted name to retain its "mystical" value.


Alan S

[Mandrake]

FWIW, when I was in my trade, refrigeration, many years ago, it was common practice to use methanol in systems that had moisture in them as it dissolves moisture and lowers its freezing point. You'll find most injector cleaners have that as a major component of their recipes in many cases the only one, but often shown on the bottle but called a corporate copyrighted name to retain its "mystical" value.

Hi Alan,

I suspected something like this. I tried a bottle of petrol injector cleaner in my car, and there was an immediate very obvious performance boost - but it only lasted for that tank of petrol.

Surely if it is methanol the boost in performance is largely due to the methanol acting as a fuel rather than any possible cleaning action ? In which case it would cause a temporary boost in performance even in a car which doesn't have dirty injectors ?

I have my doubts as to whether there was any long term benefit beyond that tank of petrol as my car is now back to giving behaviour that makes me think the injectors still need cleaning...

Seems a bit cunning on the part of the additive makers if their product boosts performance due to a combustable additive more than it actually "cleans" the engine. (if it cleans at all....)

Regards,
Simon

[alan s]

Simon,

On old carby cars, whenever I had water in the carby, a squirt of metanol would dissolve it almost instantly.
The cleaning action I think you'll find would come from its ability to dissolve the varnish that forms.
I've recently discovered a few things about oils and fluids that's quite amazing such as.....................ATF has amongst its many additives, a "seal sweller" (which begs the question what does this do to Cit hydraulics when used as a substitute? Power steering fluid is Dexron 111 ATF with additional seal swellers added which is why they sell a "leak fix" which will seal off leaks in power steering systems particularly those run on ATF; it's simply a seal sweller, and where do they use the most potent seal swellers which is suspected of being used in the PAS fluid and the "leak fix"? It's used in the special oil used in the forks of the modern day motorcycle.....so chances are, if you see a car with a leaky power steering ram seal, you can spend A$15 on a 200 mls bottle of "Special leak fixer for Power steering systems" or grab a cupful of fork oil from the motorbike shop for a few cents.
No wonder they're one of the richest industries in the World.


Alan S

[bxbodger]

Diesel injector cleaners are completely different to petrol versions, and they are pretty effective come smoke test time- if your injectors are getting on a bit its the difference between a pass and a fail. They don't harm cats, either.

But...........save yourself some money and just use some paraffin, as thats essentially all they are. Open a bottle of wynns and sniff.......

[AndersDK]

Diesel injector cleaners are completely different to petrol versions, and they are pretty effective come smoke test time- if your injectors are getting on a bit its the difference between a pass and a fail. They don't harm cats, either.

But...........save yourself some money and just use some paraffin, as thats essentially all they are. Open a bottle of wynns and sniff.......

You're right bb -
But I think there is more to it as paraffin alone dont do the trick. Here in DK the most common winter precaution on diesels was to add paraffin - or refined lamp oil (dont smell) - to prevent waxing problems.
It has never done any cleaning using paraffin.

The Valvoline stuff I bought was deep red and thick flowing - and smelled very toxic - nothing like paraffin, diesel, petrol or other common solutioners I've met in my life.

[Mandrake]

I've recently discovered a few things about oils and fluids that's quite amazing such as.....................ATF has amongst its many additives, a "seal sweller" (which begs the question what does this do to Cit hydraulics when used as a substitute?

Hmm, my car has a leaking front electrovalve, and it also had red ATF of some kind in the hydraulic system when I got it.... co-incidence ? Or a case of damage to the seals ?

Regards,
Simon

[Kowalski]

A lot of fuel treatments contain an octane / cetane improver (depending on whether its for petrol or diesel) as well as some detergent, perhaps something to remove water and not a whole lot else. A petrol engine with a knock sensor will become more efficient with better octane fuel, but a diesel won't be affected much by better cetane fuel. Diesels should get quieter with better cetane but unless your injectors are absolutely knackered I wouldn't expect any improvement in mpg. By knackered injectors, I mean they're so bad that a good percentage of the fuel injected goes out of the exhaust as smoke and the improved cetane means this gets burned, hence better mpg.

I've never found an additive that has improved mpg, but my injectors have done much less mileage than yours Anders. My older car does get a little quieter and less smokey on injector cleaner but only while its in the tank, once its gone, the effect has gone.

I've never used an additive that didnt smell like parafin, I'll have to try some of that Valvoline stuff, perhaps I'll have a look for some around MOT time

[Zirria]

I apologize for bumping this old topic, but I have done quite a bit of research on this, so I want to share my experience.

I used the STP additive https://wheelstips.com/best-diesel-injector-cleaner when I first got my TDI a few months ago. It was the only diesel additive I could find at my local chain auto parts store. I think it says something like "treats 30 gallons" so I used half the bottle at one fillup and half at the next.

Now I use the old STP bottle to carry a measured amount of Power Service (which I finally found in a big bottle at a truck stop) for each fillup. I almost always take 12-13 gallons of diesel during a fill, so I take a shade over 4 ozs. of Power Service with me, which is the recommended proportion for that brand of additive. How do I know I'm getting 4 ozs? I have an old plastic photo darkroom graduate in the garage that I measure the Power Service into before transfering into the STP bottle.

This all takes longer to type and read than to actually do. It's so easy and routine that there's nothing to it.

Don't be afraid to use additives. Don't think it's "Yet another one of those extra things you've got to do to be a diesel owner." It is no big deal, it's cheap and from what I've read here will pay off in the long run.