New injectors?

[Busterboo]

Not long ago, 2 injectors failed on my 35iS. The initial symptom was a slight hesitation in starting, which worsened over a week to the production of some smoke and the stink of unburnt fuel. The upshot was that it needed new injectors on cylinders 4 & 5 and had them on all six at the AD, paid for by insured warranty.

The effect was not just easy starting, but a radical improvement in performance, which the emptier lockdown roads have made very enjoyable. I now appreciate how much the power had declined over time without my noticing.

I also realise that popping down the local AD for a set of injectors ain't cheap, but, knowing what I do now about the effects, it's something I would happily pay my indy to replace on a 70k-mile car like mine.

That said, is there a way of extending or renewing the life and performance of injectors without replacing them?

 

[enuff_zed]

Interesting point that if performance drops off slowly you don't notice it. Worth bearing in mind.
Also interesting to know what effect it would have had to only change 4 & 5. Would it cause some form of inbalance? I'd assume the clever electronics would mask that for a while at least.

My guess would be that your question will open up into the relative merits (or otherwise) of the fancy fuels.

 

[mr.tourette]

My indi says he sees very few injector issues on cars that mostly use shell fuels due to the detergent package they use, my local garage is a shell and its the fuel station i pretty much always use..never had an injector failure on any car/motorbike in 20 years..whether thats down to the fuel I dont know but it certainly ties in with my indi's theory

 

[mcbutler]

My indi says he sees very few injector issues on cars that mostly use shell fuels due to the detergent package they use, my local garage is a shell and its the fuel station i pretty much always use..never had an injector failure on any car/motorbike in 20 years..whether thats down to the fuel I dont know but it certainly ties in with my indi's theory

Indys say some funny things, as though they keep any sort of record as to who uses what fuel and what goes wrong with their car. I personally put a bottle of injector cleaner into every tank of Tesco momentum which I believe is the highest ron fuel in the UK at 99 ron??!!

 

[Nanu]

The best advice I got was don't use cheap supermarket fuel. It's not cheap in the long run.

 

[mcbutler]

The best advice I got was don't use cheap supermarket fuel. It's not cheap in the long run.

We have to ask ourselves this 'where do the supermarkets get their fuel?' - they get it from the same refineries as everyone else and I am really sure that they dont do a 'special cheap brew' for supermarkets. Supermarket fuel pricing is generally down to the huge volumes purchased and the fact that they use the cheap fuel combined with fuel outlets on their major retail sites to draw in customers.

Out of interest does anyone know of any peer reviewed studies on the issue?? I would be binterested to research further.

 

[mr.tourette]

yes they all get fuel from the same refineries but I believe its the additive package that is then added to said fuel that makes the difference.
Personally im not too fussed where i buy my fuel from in a pinch, just so happens my local station i pass most days is a Shell, never had an engine issue in all my years driving be it car or motorbike although that could be just as much good luck as good management, I did mostly drive Hondas previously and have always kept them well serviced

 

[Dave 2 dogs]

Hi busterboo
Radical improvement, that’s quite a statement.
Was toying with the idea of doing the plugs n coul packs , your saying it’s definitely worth spending the money on the injectors too ? What sort of money are we talking about for all injectors replacement, if you don’t mind me asking?

 

[Nanu]

The best advice I got was don't use cheap supermarket fuel. It's not cheap in the long run.

We have to ask ourselves this 'where do the supermarkets get their fuel?' - they get it from the same refineries as everyone else and I am really sure that they dont do a 'special cheap brew' for supermarkets. Supermarket fuel pricing is generally down to the huge volumes purchased and the fact that they use the cheap fuel combined with fuel outlets on their major retail sites to draw in customers.

Out of interest does anyone know of any peer reviewed studies on the issue?? I would be binterested to research further.

Super market fuel is from the same refineries but doesn't have all the additives, hence cheaper.

 

[Nanu]

Hi busterboo
Radical improvement, that’s quite a statement.
Was toying with the idea of doing the plugs n coul packs , your saying it’s definitely worth spending the money on the injectors too ? What sort of money are we talking about for all injectors replacement, if you don’t mind me asking?

The injectors retail for circa £200 each

 

[SV8Predator]

Super market fuel is from the same refineries but doesn't have all the additives, hence cheaper.

And where do you get this information from? Any sources?

 

[R.E92]

New injectors are £250 each from the dealer. Up until recently the dealers were selling them at £120 each but that finished early this year.

There's no point talking about fuel quality, the failure mode of N54 injectors is not related to fuel at all and no amount of injector cleaner will help.

Heat is what kills the injectors. The early revisions of the injector had an issue where the internal metal mesh filter inside the injectors would deform and break down inside the injector, this was blamed on heat. There was also a problem of the thermal cooling oil inside the injectors not being sufficient which could be the cause of the leaking.

The injectors were revised until revision 12, there was also a technical update to the revision 12 injectors (this was only for the S63 engine initially but now the part is offered for the N54 too) which involved upgraded thermal management inside the injector so there's actually 13 different types you can get.

If you plan on keeping the car forever and have anything lower than revision 11 fitted then it's worth getting them changed. When they start leaking they dilute the oil with fuel so you can get engine damage. They also get lazy so the car feels less responsive as the spray pattern is off. There's lots of fake injectors around so don't buy them from anywhere other than the dealership unless you find genuine used ones from a scrap dealer. Used ones will need new seals fitting and the tool for that is around £100 so factor that in when buying.

 

[mcbutler]

The best advice I got was don't use cheap supermarket fuel. It's not cheap in the long run.

We have to ask ourselves this 'where do the supermarkets get their fuel?' - they get it from the same refineries as everyone else and I am really sure that they dont do a 'special cheap brew' for supermarkets. Supermarket fuel pricing is generally down to the huge volumes purchased and the fact that they use the cheap fuel combined with fuel outlets on their major retail sites to draw in customers.

Out of interest does anyone know of any peer reviewed studies on the issue?? I would be binterested to research further.

Super market fuel is from the same refineries but doesn't have all the additives, hence cheaper.

Evidence??!!

 

[Nanu]

New injectors are £250 each from the dealer. Up until recently the dealers were selling them at £120 each but that finished early this year.

There's no point talking about fuel quality, the failure mode of N54 injectors is not related to fuel at all and no amount of injector cleaner will help.

Heat is what kills the injectors. The early revisions of the injector had an issue where the internal metal mesh filter inside the injectors would deform and break down inside the injector, this was blamed on heat. There was also a problem of the thermal cooling oil inside the injectors not being sufficient which could be the cause of the leaking.

The injectors were revised until revision 12, there was also a technical update to the revision 12 injectors (this was only for the S63 engine initially but now the part is offered for the N54 too) which involved upgraded thermal management inside the injector so there's actually 13 different types you can get.

If you plan on keeping the car forever and have anything lower than revision 11 fitted then it's worth getting them changed. When they start leaking they dilute the oil with fuel so you can get engine damage. They also get lazy so the car feels less responsive as the spray pattern is off. There's lots of fake injectors around so don't buy them from anywhere other than the dealership unless you find genuine used ones from a scrap dealer. Used ones will need new seals fitting and the tool for that is around £100 so factor that in when buying.

I have had new injectors fitted recently and the ones that failed were as fitted to the car when new. They were revision 12 surprisingly. So whatever the problem was, they haven't fixed it yet

 

[Nanu]

Super market fuel is from the same refineries but doesn't have all the additives, hence cheaper.

And where do you get this information from? Any sources?

Just google the question - supermarket fuel versus named brands and you will get identical results. All start from the same minimum standards the differences are when the named brands add additives to clean the engine, enhance performance of the fuel and sometimes increase MPG. Read for yourself and make up your own mind. I know mine runs better and gives a couple of extra MPG with Shell Otimax, especially since changing the injectors.

 

[Nanu]

We have to ask ourselves this 'where do the supermarkets get their fuel?' - they get it from the same refineries as everyone else and I am really sure that they dont do a 'special cheap brew' for supermarkets. Supermarket fuel pricing is generally down to the huge volumes purchased and the fact that they use the cheap fuel combined with fuel outlets on their major retail sites to draw in customers.

Out of interest does anyone know of any peer reviewed studies on the issue?? I would be binterested to research further.

Super market fuel is from the same refineries but doesn't have all the additives, hence cheaper.

Evidence??!!

just replied earlier in the posts

 

[R.E92]

I have had new injectors fitted recently and the ones that failed were as fitted to the car when new. They were revision 12 surprisingly. So whatever the problem was, they haven't fixed it yet

I've not heard of anyone having failed index 11 or 12 injectors, it's certainly a lot rarer.

If you have photos of the old injectors you can check if they are the first or second version of the index 12 injectors. The updated version have an etching in the metal part at the top of the injector and that supposedly shows that they have an upgraded thermal oil inside.

 

[SV8Predator]

I know mine runs better and gives a couple of extra MPG with Shell Otimax, especially since changing the injectors.

It must be the fuel!

 

[mcbutler]

Super market fuel is from the same refineries but doesn't have all the additives, hence cheaper.

Evidence??!!

just replied earlier in the posts

Nope, just saying its so isnt evidence my friend just an idea/opinion.

 

[Nanu]

I know mine runs better and gives a couple of extra MPG with Shell Otimax, especially since changing the injectors.

It must be the fuel!

Nope, I kept to my usual Morrisons supermarket fuel at first until someone on the forum recommended the Shell Optimax. I even occasionally use the 99ron which is better still. Sorry to disappoint