Before I got my Jag, I had never even ridden in one, so I was not sure what to expect. I have read reviews about the AJ16 being smooth, like a Lexus. My Jag idles fine RPM wise, but there is an odd oscillating vibration between smooth operation. Not heavy at all mind you, but enough to tell my hands on the wheel that the engine is indeed on. Is this typical or do you think it may need engine mounts or something has a balance issue? It has a timing like 2 seconds smooth, 1 second vibration, 1 second vibration, 2 seconds smooth, etc...Is this normal?

 

Nope ................The least intrusive thing would be injector cleaner when you run the tank down and plugs as something is on " the edge of bad "

 

I have the same exact vibration. I put new plugs, but not cleaned the injectors yet. No change. When I put the gear in R or D no vibration/ I will next clean Idle Air Control Valve, TB and EGR to see if it improves.

 

To do a more thorough job of cleaning the injectors you can use this method . The connector is the same as the trunk lights so you can barrow one . There are basket filters on the inlet side of each injector . In P the pulse width or time is at it's lowest so if you have a unresponsive or dragging injector the resulting pulse is even shorter not to mention a not optimum spray pattern from deposits

 

Interesting. Has anybody run Sea Foam Motor Treatment through the vacuum lines to clean the injectors? If so, which line is best? It sounds like the most effective way to clean them without removal of the injectors:

"The Sea Foam website recommends locating a PCV hose or the vacuum brake booster line. If you are unfamiliar with vacuum lines, you should consult a certified automotive technician or ask your know-it-all buddy for help.
Before you disconnect this line, you’ll need to start your engine and let it idle until it has reached normal operating temperature.
At this time you can disconnect the vacuum line and begin SLOWLY pouring in the Sea Foam Motor Treatment. You will only need to use about 1/3 to 1/2 of the can.
As you are pouring the cleaner into the vacuum line, the engine will begin to run rough – don’t worry, this is normal. However, you don’t want to pour it fast enough that it causes your vehicle to stall.
Now, turn off your engine, reconnect the vacuum line and let the engine sit for 5 to 10 minutes. This cool down period is called a “hot soak” to allow the cleaner to penetrate the carbon deposits inside your engine.
Next, you’ll need to restart your engine in a well-ventilated area and take it for a test drive. As the cleaner continues to run through your engine, the exhaust will give off additional fumes. Continue to drive for about 5 miles to allow the cleaner remove any remaining deposits from your engine."

They appear to have removed this info directly from the Sea Foam website though (probably due to liability and desire to have you use more in your fuel tank).

 

Vacuum line route will not follow the path of fuel inside the injector

 

True, it would only provide some collateral cleaning for the injectors that way, but it would provide the best top end cleaning otherwise. Between the vacuum/intake entry directly, and in the gas tank, it should do a decent job of cleaning them out without having to remove the injectors.

 

The only thing which goes through the injectors is fuel. Putting additives into the inlet track or vacuum lines will not clean the inside of the injector, which is what Lady P is talking about.
There are some fuel additives which claim to clean the injectors, and perhaps they do, but I have them firmly in the same headspace as snake oil.....
If you have a blockage in the filter in the injector, bear in mind it is already resisting being washed with high pressure fuel more or less continuously, so will need something pretty potent to remove it in the absence of being physically cleaned.

 

In order to remove the basket filters in the injectors you can take screw with the pointed end filed off so you have more like a stud . By twisting and pulling as you thread in and bite the filter will come out . Replacement filters come with the with the new O-rings . The O-rings are Viton fuel resistant and not common rubber . The AJJ6 valve head in the linked post is of a underpotental flow in the author's bench flow measurements . And what Sea Foam may do as a vacuum line method is clean the throat area as the AJ16 engine builds up alot of grime from the crankcase vent gasses recirculating back by design into the intake . A Jaguar TSB installs a oil / air separator to address this and you may or may not want to look into this depending on the service life left on the vehicle . The early production AJ16 had an idle problem addressed by changing the cams as was a weak spot as they designed the lobe overlaps .

https://www.marcorubber.com/o-ring-m...-reference.htm

 

It looks like I should be able to get some cleaning value out of the direct intake method and gas tank additive (I'll do that first as an experiment of minimally invasive maintenance), but the best method would be to remove and clean the injectors entirely, removing and clearing the basket filters as Lady P suggests as well.

Are there any injector repair kits out there for our AJ16, containing both o-rings and basket as you mentioned?

 

The seals are Jaguar part number EBC8492 a pair x 6 and the baskets are somewhere I found earlier

https://www.jaguarforums.com/forum/x...d-kits-150503/

 

Looks like going through Mr.Injector (or similar service) might be the best method of getting it done right. For the hassle of doing it myself, I think I might rather spend $120 on that route.