engine/fuel additives
 

I have an early 98 XK8 with the non steel sleeve engine. I have to assume it was never replaced so I have some concerns.

Am I able to use a fuel injector cleaner? or even an oil additive like Z Max?

I have used these produces on my Corvettes & BMW's. They have run better with improved gas mileage.

Will these types of products wash the cylinders and cause them to fail even faster? https://www.jaguarforums.com/forum/i...cons/icon9.gif

Not sure what Z Max is but I use BG44K once a year and has not created a problem. Your fuel presentation with a Nikasil block is imperative. I did a great deal of research to better understand Nikasil and I documented it on my page Jaguar Nikasil Engine Blocks & Jaguar Nikasil & Sulfur I hope this helps.

Irrespective of what type of engine you have, no additives are required or recommended in your Jag- especially in the oil!

See post #5 by Brutal:

https://www.jaguarforums.com/forum/x...roblems-33619/

As much as I want to believe marketing, I have become a little bit skeptic over time.

Regarding engine restore, if it does what it says (so filling up spaces), it should only be used as a last resort imho.

One of the good characteristics of the nikasil lining was the hard silicon particles that would offer small pockets where oil would be retained, to offer a better protection at start of the engine.

So for the short term it might help, but longer term could have a quicker deteriorating effect.

Please note I have no background to thoroughly understand the above, am only using the marketing words from 2 different companies.

In Northern Va. all the Jaguar dealerships use BG products and BG44K is one of them.

Zproducts are crap. (oops I work for the parent company) my own results of Zmax in the oil on my own Jag has been a loss of 2mpg. Which returned to normal when I changed the oil again an left it out. Did that 2xs. once on the original formulation, and then on the "reformulation" to keep the many states AG's off the companies back. Sorry I just call it like I see it. I have used "Engine Restore" with great results on worn, loss/reduced compression engines many times over the years. I dont think of it as preventative, but has saved more than a handfull of engines that should have been rebuilt. Keep the oil changed and dont overheat the engine and you probobly wont have issue. BG44 is recommended by Jaguar in a bulletin/SSM to us to use for misfires/rough running. But it has comeout and been dircted more at the new 5litre engine with direct injection. can be used quote "UP TO 2x's in 15k miles at the customers expense"
I know Mikey always likes to have me show stuff but I am not gonna spend more of my time that I dont get paid for here to find/lookup stuff just to prove a point. its out there I dont make this crap up.
I think the bigger issue IS dirty injectors that dont spray well and on cold starts, wash oil off walls and wet the plugs resulting in a "flooded engine"
The Nikasil blocks only have issue with blowby past the rings and a degradation of compression

Chemical cleaning of the injectors has been approved by Jaguar for a long time.

Here are some TSBs from way back in 2004.

bob gauff

There's a big difference between 'using' stuff and 'needing' stuff. Every garage, dealership and car parts store has a line of products they push- for obvious reasons. This doesn't mean that they or work or are required.:icon_deadhorse:

An honest answer to this ongoing question would be to see what happens if use of a product is discontinued and the driver is not made aware if the car has the product installed or not. It's all too easy to fall into the placebo effect of pouring $20 into the gas tank and instantly 'feeling the difference'. Nothing less than a blind, and better yet, double blind test would have any credibility.

Since the vast majority of owners do NOT use additives how do we explain that their cars run just fine?

I do acknowledge the TSBs that offer a procedure to an existing problem and will accommodate that in future answers- but again this is an in-shop attempt to fix an existing issue and is NOT the same thing as pouring a bottle of liquid into the gas tank now and then to prevent a problem.

Garbage like Z max and similar are well known scams that have been through the court system and I'm sure there's a few dozen more 'octane boosters' that the fart pipe crowd love so much deserve likewise.

Much like the oil wars, this issue will never be resolved and the 'use what makes you happy' wisdom prevails. :icon_bump1:

once a year on the BG44k for me, like clockwork

My sister uses the cheapest, crap gas in her car all year long (possibly leading towards a female reference, but I shall refrain) and then she tells me her car is constantly hesitating when she tries to really accelerate hard, like making a stop light before it turns red, or in her most recent case, making a left turn at the end of a green light cycle..she said it scared her because it almost died mid intersection. I left her a bottle of BG44k in her cupholder and told her to put it into her tank when she gets her next fillup, and she said she didn't have any other problems afterward...till maybe 6 mos from now when the buildup gets bad again....oh well.

moral, BG44k is good preventative maintenance, especially for a new car that you don't know the history of the fuel system. For the oil, there is a few people that had some sludgy internals and asked about how to get it clean again...a few more frequent oil changes, coupled with a short run of ATF added a few days (maybe a week) prior to the oil change, will get most of the neglect 'crap', if there is any in your engine.