Yes, it is not easy. I used a combination of a 17mm wrench and deep socket after I cut off the wires. A whole bunch of universal joints and extensions too! I think the sensor on the rear pipe isn't too bad to to do, the front pipe is very difficult, because it's tucked between the exhaust and the engine. I got it from underneath the car.

I'm assuming the European cars have the sensors downstream of the catalytic converter? The additional ones North American cars have are between the manifold and the catalytic converter and are fairly easy to get to.

 

I bought mine from British Parts and they were the Titania type so you should be OK which is nice. One is fairly easy to get at as I recall the other one I took to the village garage and the young lad undid it quite easily which surprised us both but he was standing up under a lift. On your back under the car would be rather different.

You can get used MAF quite cheaply on eBay in the UK. I got one for 12 UKP and it seems fine. I think new ones are a lot more expensive

 

Update: My beautiful Jag has been running very well for the last days with only one or two incidents featuring the drop in RPM, and nearly choking. Yesterday however it died again, and the transmission warning light came on. It started immediately again, but I had to adjust the throttle by foot at every stop til I came home. I have sprayed startgass along some hoses that I believe are vacuum hoses ( maybe someone could point out which ones?) but nothing happened while running in idle.
I changed sparkplugs again yesterday to an equivalent to the Champion RC12YCC called Brisk 0016 A-Line DR17YCY, and they run very well, but on the first test drive yesterday the car ALMOST stalled again. This morning it ran perfect again, but I guess the problem is still there.
I have received 2 Oxygensensors from Britishparts, but I don't believe I will manage to replace them on my own. It looks impossibly tight, and I can not find a "how to" on this forum. I have also ordered a brand new MAF from the UK which will arrive soon.

In the meantime I have opened the famous "ski-slope" as I noticed a clicking sound whenever I touched the brakes. Tried spraying some electrical cleaner spray in the solenoid but nothing really improved. Does anybody know where I can order the part and what its called? I have seen this is a common issue here.

And does anybody have any other thoughts regarding the idle? It seems strange that its such an on/off issue that happens once in a while. When removing the new NGK iridium plugs I noticed that they were also very black and sooty. Been driving in the city with some kickdowns recently and only managed around 9 mpg, or about 3,3 l/10km.

I also wanted to try this "Arcing" (?) method but I have not understood how it is performed. Running the car in the dark, and removing the coil cover to look for light at the coil? Or removing the coil as well? Someone PLEASE explain I have one spare coil now from britishparts, so I was really hoping to find a faulty coil.
Best wishes from Norway - Enjoy your weekend in one of the most beautiful cars ever made

 

The O2 sensors are accessible from the top and someone has written it up but you have to cut the wiring I think or possibly use a crows foot spanner. As I mentioned I took mine to the village garage and watched. Looks like if you have a ramp it is way easier and took 15 minutes to change the awkward one but it came out very easily.

Coil arcing? Someone here suggested take the cover off, get the cardboard tube inside a kitchen tissue/paper roll and it fits over the waxy looking bit of the coil you can see having taken the cover off. Then you can peep down there to look for arcing even in daylight with the engine running. Worked for me.

Did you get an OBD scanner? I got a cheap (12 UKP) one and used it with the Torque phone app and you can watch the engine real time which is sometimes informative and cheap. Isn't there the suggestion that stalling can be unmetered air? So presumably the engine side of the MAF. But you checked for leaks in the bellows as I recall.
I worry about the air tightness of the servo vacuum hose on mine as it is definitely a loose fit but I don't like the sound of the clip that holds it in so haven't changed it. My Jag will stall once in a blue moon at idle just as I am pulling away slowly. Restarts instantly.
I hope you get this sorted.
I'm sure I only get clicking under the ski slope when I first put my foot on the brake to release the gear shift. If no-one else comes along I'll check later today.
Mike

 

Old thread started by me, all the info about the switch is there.

>click<

 

Does your car have 2 or 4 O2S? If only 2 like mine they will be the lower ones. There is no way you can change both of these from the top but if you put the car up on ramps or blocks you can get underneath to to reach them. The cables up to the connectors are a bit difficult to get at. You can open the main wiring loom on the firewall and relocate the connectors to a place where you can get at them if you want. I did this partly because the O2S I bought had slightly shorter leads so would not reach the original connector position and also so it is much easier to get at the connectors.

 

I have 2 as far as I know.. Below the manifold. Looks like the replacement I got also has a very short cable, so it will be tricky I guess. The worst part is probably reaching the connectors at the rear..

Not my car but the same engine I think :



And a big thank you to Maraud for the link regarding the annoying click. I will try once again to clean it

DRMike: I have not yet found a suitable OBD tool here.. I will probably contact a garage to have it read. The clicking sound comes every time I touch or release the brake pedal while driving.. very annoying.

I also contacted the official Jag dealer in Norway to ask if they could perform a service or test to search for errors. Norway IS an expensive country, but still.. The yearly service(fluids,filters) would be usually somewhere between 850-970 USD. (760-870 EUR) and they charge 243 USD per hour (220 EUR). I think I will look elsewhere for my regular service

 

I'm 99% sure this teh OBD scanner I bought and it seems to work pretty well

ELM327 HH OBD Advanced Bluetooth 2.1 ODB2 OBDII Car Auto Diagnostic Scanner Tool | eBay

Your mechanics know how to charge for work!

 

An update.. I installed a new MAF, a brand new one from ebay, and after the first 10 min drive to work this morning it seemed all smooth and perfect. I am keeping my fingers crossed though. I noticed that this maf has silver plated contacts, not the gold ones like the original Lucas unit. Could this cause any problems?
I have not yet dared to touch the lambda sensors, but this, and a new fuel filter will probably be the next step. I will give the new maf a week and then I really hope I can close this topic as solved

 

That's good news.

 

I'm surprised no one has mentioned the TPS, which seems to wreak all sorts of havoc on this engine. Not a cheap part, but a possible suspect, especially since the throttle body was clean-ish? The previous owner, or service technician could have sprayed a bunch of solvent into the throttle body, and since the TPS is on the underside of the pipe into the engine, guess where that solvent goes? The TPS.


The only other suggestion I have, based solely on the spark plug condition, is the fuel regulator. This engine does not allow you to put a gauge on the fuel line, so unfortunately there is no way to diagnose a failing fuel regulator. (I think)


Lastly, I am concerned that you are not able to use a OBD2 reader for your car. As far as I know, the AJ16 engine is an OBD2 compliant engine, so you should have no issues. I'm wondering if that could indicate a problematic ECU?


I do support changing the oxygen sensors, those can also cause this kind of problem. I look forward to reading the conclusion of your efforts!

 

Day 2 and the car runs perfectly so far.. the idle is much stronger and it really seems like a new maf did the trick. I will give it a few more days though before I go all happy about it.

In the meantime What in the #*** is the point of this clicking noise and how do I get rid of it?? Every time I touch the brakes it goes off. The sound is mechanical as it's touching metal against metal and/or plastic. .

See this video I did yesterday

 

Ofcourse it was ;-)

About the switch, its an inhibitor switch, its on the right side of that J-Gate.
You need to unscrew the top plate in order to see this switch. Put the gear in drive then put the facial plate on the side. Now you can see that little micro switch on the right side, attached to a brass plate.

So what probably happens is that the switch is dirty and it makes constant contact now. Take the contact spray, soak the switch and try to clean it, wiggle with the sprite etc. If you touch it and release the sprite or press it, you should hear the switch, not as loud as your solenoid tho.
You can also try bend the sprite from the switch if its to low to make contact with the shifter. Be carefull tho not to break ;-)

So when the switch is pressed in and you press your brake, the solenoid mechanism ( the click you hear ) is unlocked and you can move your shifter out of park. If the switch is not pressed and you press your brake, the solenoid is not active and in locked position so you can not move the shifter out of P or put in reverse while driving.

 

Thanks for the explanation but I already tried cleaning that switch with no change in the clicking issue.. It is rather loud so I HAVE to do something about it before I go crazy.

 

Replace or keep soaking it till it works, maybe never
The reason I have a spare is because it failed on me too more the once.

Try to grab the sprite of that little switch and move it forth and back. Don't press the brake yet. Listen to the switch if you hear make it contact. In the video you can clearly hear the little switch working.


Here you see when i press the switch and brake, you hear that soilenoid clicking you referring too. When i don't touch the switch and brake it silent.

 

Maraud is correct that this switch (or the wiring to/from it) is definitely your issue. The switch is a simple on/off switch so unplug it from the loom and test it with a multimeter. If the switch is good then check back at the BPM where the signal goes. If the switch is bad it's easy to replace with a standard micro switch that costs very little from electronics stores.



@Maraud - Just some technical clarification...

Side note*: Many people complain that their car won't start, many times it is this switch that's not pressed in when in park. So the P does not illuminate and the engine won't start. Wiggling with the shifter many times solves this till the P glows red, or fixing the switch.


This is a common misconception. The Not in Park switch plays no part in the starting process. The Park/Neutral signal required for the Start sequence originates from the Linear Switch (which is the big black box on the right of the Not in Park switch in your video).

 

Thanks, for that. Now I think about it, ur totally right.

 

There is no doubt anymore. The idle is so smooth and there is no signs of stalling or choking. Fuel usage is also back to normal . The new MAF did the trick. Thanks to everyone for all your very good suggestions!!

 

I just got the obd and got 2 codes. Had to chose a new jag xj model in the setting but I'm not sure if that's relevant really. Anybody know these codes?

 

If you have P1775, that only means the TCM sent a request to the ECM to turn on the Check Engine light and alert the driver.

1193 code is the downstream lambda heater circuit, or O2 sensor.

Could both be related with the replaced maf. Have you tried erase them and see if they come back? Others will maybe chim in.