Failed and seized injectors

[BobHarrington]

We all read and heard the horror stories of failed injectors, which are then found to be seized into the cylinder head, and the subsequent cost in time and money. I’m told they fail due to a build up of carbon, and the risk of this happening can be greatly reduced by an annual treatment of TUNAP 979 furl additive.
Before I rush out and buy some, I thought I’d ask you knowledgeable guys out there what you think?

[MikeM]

There are a number of injector cleaning additives on the market. I have used them with diesel engines and older early fuel injected engines, not heard of TUNAP 979, certainly shouldn’t do any harm. I think what’s most important is to always use a premium high performance petrol such as Shell V-Power (or equivalent) They contain cleaning additives within the blend and the lowest ethanol content. The seizing issue is another matter altogether.

[BobHarrington]

Hi MikeM, I always use the premium petrol ~ does the brand matter? Is any one, better for us than any other?

[DaddyDarren]

Hi MikeM, I always use the premium petrol ~ does the brand matter? Is any one, better for us than any other?

Have a listen to Episode 3 of Chris Harris & Friends Podcast…

https://podcasts.apple.com/gb/podcast/t ... 0670131951

For me, the best motoring PC

[EnglishPhil]

Just happened to have received October's Jaguar Enthusiast Magazine. There's a Q&A section with Tom Robinson of Swallows. They recommend using Tunap 979 for preventative maintenance to help clean carbon build up. After that you can use the cheaper product (974) that prevents recontamination. Yes, the 979 is expensive (£54 on Amazon) but compared with a set of new injectors it seems well worth it for peace of mind!

[Cluck]

From what I've read previously, the only additive known to do anything of note is PEA. The Tunap 979 does contain that in 5-10% levels, but so does the 974. Redline SI-1 contains nearly 30% and costs <£20 a bottle - https://www.opieoils.co.uk/p-1028-red-l ... eaner.aspx

In terms of 'which fuel is best', all of the premium unleaded fuels contain better cleaning additives to some degree or another and they will all say they are better than their competitors. I try, where possible, to use Tesco's Momentum fuel, adding a small amount of additional cleaning additive with every fill (Archoil AR6900P Max, as it also contains PEA) and a bottle of SI-1 once a year.

EDIT: Worth noting, I am NOT an expert in these matters (far from it!) and haven't done a lot of research. I also have no ties or links to any product sold or places selling them.

[MikeM]

Hi MikeM, I always use the premium petrol ~ does the brand matter? Is any one, better for us than any other?

If you can get Esso Synergy Supreme 99, it is considered one of the best fuels for engine performance and cleaning. It also, (unless it has recently changed) for some parts of the country has no Ethanol content. Which is great for older/classic cars.

[MajorTom]

My approach...

to reduce the risk injector failure:

- Only use branded high octane petrol
- Use a bottle of injector cleaner with each annual oil change/service - my dealer includes that

to reduce the risk of injector seizure:

- If the car will be washed or subject to heavy rain, put on the engine cover which I've modified with additional rubber flaps to divert any water that comes in through the bonnet vents from the engine block. That's a rather obvious mod for any RWD F-Type with the original bonnet design. I have a black pack car which includes the tighter shrouded bonnet vents which don't let that much water in. If you have a non-black pack car with the open vents this mod is even more important.
- Keep it garaged and nice and dry as much as possible.

[WShudds]

I use BG44 as it's recommended by Jaguar. The product page talks about a high amount of PEA without specifying the ratio.

https://bgprod.co.uk/index.php/products ... stem/bg44k

I learned from a specialist that the "secret" is in how these additives are used. Don't throw a bottle in when you'll go on a long motorway journey when your fuel will be used up in a day or so.

You need to give it time to work. Ideally, the car should go through at least 13 driving cycles (drive for at least 10 miles and let it cool down for at least 4 hours each time) within 1 to 2 weeks to give the additives the best chance at breaking down the carbon deposits.

I make sure that I do at least one Italian tune up while the additive is in the tank.

[Cluck]

The problem I have with BG44K (I did use some a few years ago) is that their Safety Data Sheet (SDS) makes no clear mention of PEA, despite their web-site claiming high levels of it being present. Given their claims, I'd like to see some evidence.