HEY GO HERE, this is a well written page for Idle Problems, BUT really i dont know why nobody talks about unless your looking for more on the subject. Here is a bunch of information supporting my temp way to trick the ecu when running in normal. THIS page gives you a world of information of what you should check.

Jaguar XJ6; Jaguar X300; Jaguar XJ6 3.2 Sport; Miscellaneous notes

 

Dear Peter,
You might have an answer to my problem. 1995 XJ6
- car starts no problem
- engine iddles no problem
- When I take off I have a small and short "shaking"
- When I accelerate slowly the engine acts like it is "witholding" or eventually not getting enough gas. it does not accelerate until I really step on the gas pedal, then it accelerate strogly and fast.
- Below and up to 6O or so mph I have the same phenomenon, it gets better when I go up to 70 or 75 mph.
- When I stop the car I have s strong smell of gas but I cannot see any leaks anywhere
- I only get 12MPG as average ! ! !
Do you think it could be the ECU ?

Thaks for your input

P.S. The guy who had the car before (only 2 weeks ago) had jumped another car from this one and directly from the battery and maybe he did dammage some electronics

Thanks

 

I made that video on Friday. I wasn't even touching the accelerator. I think I really need sme advice! Please help!

 

Been through this a few times myself......

One or more of your ignition coils is failing.

Sometimes (not always) the offending coil will give off a flashing/arcing if you observe the engine running in a darkened garage.

Cheers
DD

 

Any other way to test the coils? I don't want to have to replace them all.

 

Any way a bad coil can cause my high idle as well? It's at 1600 in park, when its not freaking out.

 

With a multi-meter you can check primary resistance, which should be .75 ohm.

You could swap out one old coil with one new coil on cylinder #1. If no change, go to cylinder #2, etc.

Try the darkened garage trick first, though. You might get lucky and identify the bad coil very easily.

Of course any of these methods must be tried *while* the problem is occuring...or nothing will be revealed.

Cheers
DD

 

The high idle is almost certainly a different (but very common) problem. Lots of archived info on dirty throttle body, throttle cable adjustment, Idle Air Control Valve, and the like.

Hate to paint a bleak picture but brace yourself for the possibilty of labor and aggravation in solving high-idle problems on these cars.

Cheers
DD

 

If you want to buy a coil I strongly suggest this:


Jaguar XJS XJR XJ6 Ignition Coil 95 97 | eBay


Thanks to a fellow Jag owner's research this has been identified as the same coil from the same manufacturer as the Jaguar-boxed coils you'd pay $400 each for at the dealer. The only apparent difference is lack of a "Lucas" label.

I suggest avoiding the $50-$60 coils offered by many vendors. A pattern of early failure has developed with these el-cheapo coils.

Cheers
DD

 

Thanks for all the info. I did take apart my TB and cleaned everything. And after I got it all back together was when it started the bogging down when I accelerate. Now it got so bad it now chugged all the time, not just after I drive it for 20 miles. I think this car is going to be the death of me, or my saving account. Going to take it to the dealer on Thursday.

 

A few years old thread but I'm about to buy a -95 xjr (x306) with rough idle, poor gas response like it does not want to rev and it stalls on take off. It's got the getrag 290. Do these tricks you wrote about apply to the x306? (I-6 supercharged) I don't know much about jags but I'm getting the car for peanuts.

My idea is to get it running and see what the fuzz about jags are at first. Later I'd like to find an old body to start a Pro-touring project or build a brittish hot rod. If rod; Fullers ESB Ale cag as a fuel tank? Complete Tea preparing station in the glove box? Who Dares Wins pin striping? Interior made from tweed jackets? Hehe, this is going to be fun...

 

Any Codes? Rich/Lean? codes?

 

Havent checked yet. Seller said it felt like it was running rich tho so I guess he smelled the petrol spjewing from the pipes. I have yet to see the thing IRL. Just thaught I'd get a head start on the troubleshooting.
Found a cheap Ac Cobra replica body today. Might build an Ac XJR Super Serpent. I meen, you get everything with this car. Indipendent axles, LSD, manual gearbox, big engine AND a supercharger. If all goes to hell I'll just megasquirt the thing and buy DRIFT gauges... MAN I'm excited!

 

Hello:
Last year I purchased a 1997 XJ6 4.0 VDP.
She has 65,000 miles on her.
Last week I started the motorcar up and noticed a sudden vibration from a very rough idle, (it has since stopped idling rough and the check engine light came on) The rough idle eventually lead me to this post. I have not driven the since I noticed the rough idle, just have started it 2-3 times in the garage for about 2-3 minutes each time.
I have been in touch with Welsh and SNG Barratt and talked about replacing the coils and surprisingly enough got two different responses on prices and quality.
But the main point for this post is that since the engine idled rough – the check engine light came on. If I swap out the coils, will/should the check engine light go of by itself?
Thank You,
Wayne.

 

My car was in accident well my son n a stone wall. I replaced leaking radiator water pump battery crankshaft sensor n car finally kicked over after 2 months of me yes a 52 yr old woman worked on my car my self!!! Anyway cables on battery were not to secure so i tightened them and alternator belt and i believe belt is frayed n while car was shaking at idle I smell rubber burning?? I believe water is in old gas any suggestions?

UOTE=PeterKiryluk;512229]Sometimes to you get codes 300 306? Or no codes ,Did you Check the temp sensor, The way to do this is, get the car running hot and i mean like HOT not getting it up to normal.
Step One, Find your Temp Sensor, it has 2 prongs, you will only notice a difference if its fully hot. Think of the temp sensor as a changing RESISTOR that constently tells you ECU Computer how much air fuel is needed to make the car run smooth and not like poop. Run it till its hot to touch the top of the motor, may take like 30 mins of idle from cold

Step 2- Pull the plug connector off while running and hot. Give it a moment and get in your car to see if you feel a difference. Remember its a resistor, so by pulling it off while its cold, it will eather still run like poop, or stall, or RPMS will go up and the gas pedal when pressed will not come down intimidatingly.

STEP 3 Now that its hot and you noticed a bit of a change with it getting smoother, no more shaking, bucking uneven motor idle. Find your self an old radio of some kind or just go to radio shack, or what ever you don't mind destroying to get the part that controls the volume.

Step 4 This Volume control slide switch or knob, should have 3 ends on it if it has more you need an ohm meter. Anyway This is called a Potenchiameter (sorry its miss spelled im Polish) gave it 7 tries still cant spell it right lol) This "Volume knob only controls ohms" Its not a voltage regulator, A switch like a light switch to your house is different, it send out too much power. The Volume switch only controls sound, and as you remember you Speakers require less power, and the Potenchiameter Volume Control Switch gives you better control over smaller amounts of power "Eg: Volume" By holding back the power or letting it thrrugh to complete a DC currant. Because yours speakers are always in a circle, they are always DC. - This is the important part" The holding back of the currant is the resistance. In a thermometer the heat makes the coil inside expand kind of like a CAR THERMOSTAT, and the amount of spring conecting with the shell is what lets the power resistance flow or not flow. Like a sink faucet, but instead of the handle you need a DC power loop.

IN YOUR CAR - The Thermostat switch is controlling the flow of power your to your ECU, by relay.
The relay with 2 DC power Loops
just has 4 prongs, or more but you need the first 4
2 for the main power 12 Volt Car Power making a loop to the Load or (ignition, Fuel Control, Idle Air control valve)
2 for the controlled Change DC power loop, making the relay switch on or off the controled sensor or what ever else that has a purpose of monetring something, it could be a photon cell it really does not matter.
THIS Power from the Temperature sensor or any other sensor, is always the same.
RESISTANCE- Power flow, much lower usually, depending on what you need it to control. THUS the need for different relay MODELS.

ANYWAY, the Temperamental SENDER SENSOR needs to change resistance like a car thermostat in your JAGUAR at all times. Making the DC power loop to your ECU"( a bunch of much smaller relays combined on a silicon panel).

This Power then passes in the circle to the first 2 prongs, < inside is a wrapped coil, which makes the power much greater, and at the same time creating a magnetic field. Like in an electric motor but, it does not rotate, instead it slaps to-gather the other side of the RELAY that go to the other 2 Prongs. This is done by a metal tongue that is not connecting to the power of the other-sides dc circle loop, but pushes a little plastic plate , (like a metal plastic sandwich, from the first half of the relay using the smaller voltage of OHMS to your Temperamental Sender Sensor.

This prosses in your x300 Controls amount of FUEL, the amount of power to the coil packs, and the amount of air the idle air control do-hicky is letting through. A very minuscule difference as the system will still be on BUT its very important for your Jaguar to idle smooth.

CHECK IT MY car started this problem at 150,000 miles. So just find one and put it in anyway to avoid the problem. This will also cause stalling when you let go off the gas and apply the breaks at intersections. The stalling and roughness IS ALWAYS going to show its ugly self, when you temperature sender is LYING to the ecu, making it do things it wouldn't normally do. A real bad influence if you ask me.

ANYWAY, you can use the volume control of anything Usually 3 prongs, your only using 2, most are going to be the rightest 2 prongs. Run a wire with 2ith 2 prongs to the TEMP sensor PLUG. And then show your wife how to drive it until you get the part.

So Volume knob turn all the way to the right MAX to COLD START,( it will NOT start if your resistance does not match the actual temperture of your motor.) YEAH THATS RIGHT READ THIS PART UNDERSTAND IT Before you start messing with the coils for no reason.

You can also tell your sensor is messed up if your car is getting less then 19.9 MPG on average living in a suburban town. You can smell it, raw gas, you can see it when you start it cold, lots of steam and raw fuel out into the world out of your pipes.

Coil packs do go, but really only when its really really hot, and the Ways to tell that is not being able to go up hills, or beyond 2000 rpms while your moving in your car or it chokes. And when its cools down its ok. again. THISCOIL pack problem can be solved, by taking all of the old crappy Lucas Garbage coils, out of your car and chucking them as far as you can throw them. You can do what it did to that, Go to ebay find Lincoln LS style coil packs, they will fit your car, you will have to cut off the screw loops with something. I pushed mine in so they are about an inch sticking out, and covered them with original cover. This design is much better because its NOT HUGGING a hot as* engine during peak summer weather. Plug design does not fit the male to female body, but it does fit the sides of the plug and the prongs perfectly just flip them upside - DOWN from yout jaguar to the Lincoln LS coil pack.

NO matter what people will tell you Jaguars are temperamental they need special really expensive 80 dollar plugs for each. Is complete non-sense. When you have a problem in your Jaguar, Call an electrition, not a mechanic. Because by the time they figure it out you will probably have paid off their house. You can get LS plugs ALL of them for 70 dollars and it works i will have to post pictures to show you guys how it works. So you can be free from the BS.

And the car runs just stronger. the coil packs from a lincoln are 3.9 and 4. something i forget but a bunch of cars use them. Stolen from the Jaguar a while ago they even have a really close plug size and all just upside down. and that is the tricky part. BUT hey for all6 i paid 70$ with shipping YOU cant beat that with a stick, https://www.jaguarforums.com/forum/i..._deadhorse.gif

Also while your getting your Lincoln plugs.

GO to the junk yard, find a Lincoln mark, with 4.6 alternator on top, locate the AC wheel, just like the little plastic wheel in your jaguar that costs a 100 dollars and buy it for 5. THE WHEEL IS metal, it has the same sized thread and same size bolt inter fitting with the JAGUAR completely and really easy to install. Just do it because the plastic crap, Jaguar put in breaks a bearing and then burns a hole in the plastic wheel and rips your AC BELT.

I can go on an on, my car runs great and its really cheap to maintain. Looks like million dollars and yet its unlike any standard model. You should see my solution for the Extra Trans Cooler/ Radiator Fan setup from the original. As the motors start to shake because once again the bearings are cheap. Anyway if you need some help, im happy to help, only on xj6's sorry haven't owned another models. Beside every single Lincoln ever made, until they made air suspension, so now i only use their parts LOL[/QUOTE]