I'm literally sick to my stomach. I've noticed an occasional hiccup when I started last couple weeks, not always but every once in a while. Always corrected itself in less than 30 seconds.
S I just parked in front of my house, ran in and when I came back out it did it again but this time it literally barely cranked, then ran soooo bad. As if it was flooded and wanted to die. And kits as if the gas pedal has no response.
And NO codes. Nothing.
It's a 2002 with the second gen tensioners but wouldn't I get some kind of check engine lit or code or something??
Throttle body sensor?

 

The first thing that comes to mind with any mystery issue is battery voltage. A quick charging system/battery test at a local auto parts store will identify a problem or point you elsewhere.

 

Haven't noticed any battery issue although I have had to reset the window several times because it keeps dropping down when I lift the handles but won't go back up.

 

Classic signs of a low battery. These cars hate that and will summon the electrical demons seemingly at random.

 

I just read Jeeves and the jaguar about the carbon build up on the butterfly valve in the throttle body. It sounds exactly like that. I even noticed a couple times its jumped when taking off from a light. AND it never does it when cold.

 

Battery first at the AP store . . . then they sell TB spray cleaner.

 

Easy to check. Remove the large hose from the throttle body to the MAF/air box (two bolts and a clamp) and take a look. The inside should be shiny and smooth. If you see a brown ring, it might be sticking there. Work the butterfly manually and see if it is sticking.

I would still have the battery checked. The window issue and the slow cranking point a battery issue, even if it has nothing to do with the poor starting.

p.s. Test point is giving you good advice.

 

I read that the Sea Foam product was a good TB cleaner, you'd better check 1st what u use with the extremely knowledgable guys on here tho' - You'd be amazed how the XK8 gives up the ghost even if the battery is a little undercharged - mine limited everything till it had charged up itself on a little run.

 

I ran Seafom in the gas tank 2X and it is SIGNIFICANTLY smoother. I am sure there is no magic involved but I am very impressed at the difference.

But for this particular situation my money is also ON THE BATTERY.

 

If you are talking about the sea foam stuff you put in the gas, that won't clear the throtte body. It doesn't get near the TB, it might clean the valves and injectors but even thre its effeciveness is questioned by many.

If you want to clean the TB I would reccomend removing it and cleaning it with carb cleaner ... don't get any on the electrical parts though.

 

I started thinking that yesterday my tank was low but today it was reading 3/4 full. So I started pouring in a gallon of gas and heard gas running somewhere. There's a damn leak under the back tank on the left side. The damn thing is out of gas. So is would it probably be a fuel line? Hopefully not the tank!!

 

Phil...take care of the battery before you do anything else. There is a good chance you will not need to do anything else.

 

Except fix the fuel leak!! It won't even hold enough gas to start it.

 

Phil...+1 on what WhiteXKR and others have said about replacing the battery. The windows on my XKR were doing the same as yours and I was experiencing other electrical gremlins. I replace my battery two weeks ago and bye-bye problems. Replace your battery, then repair your fuel tank and you'll soon be sittin' behind the wheel with a big smile back on your face!

Cheers!

Jon

 

You know... Although I agree that the battery is the prime suspect for starting issues, if your tank is leaking gas onto the ground I would address that first.

Raw gas, plus spark when changing battery, is not a good combination.

Steve

 

My 1st thought was low fuel pressure when reading your post, so you may want to check the pressure.

 

No it's not the sea foam stuff u put in the gas, u remove the throttle body, i'm happy to be corrected but i think if you put your foot on the gas pedal (as u guys say) turn the ignition key ( but don't start it) then switch to off again wedging the gas pedal down the throttle body stays 'open', u then remove it and clean it, reattach and spray the sea foam directly into the throttle body, hook everything back up )may as well clean the maf while you're at it) - then start the car and let the sea foam do it's work. I took mine to be Terracleaned a few weeks back but my engine was running ultra clean so it didn't need it - this might be to do with it running on LPG ? It has been well maintained before i bought it six weeks ago tho' - obv get ur fuel leak fixed before u do anything tho'.

 

S exactly what would be n the area almost beside the filler neck behind the left wheel? I just can't get under there wo check since I lowered it. Is running out I guess at the lowest point since it won't hold enough fuel to start. Is that where the pump is?

 

maybe suss out where you're gonna get it repaired and put in enough gas to get u directly there - it's that or get it taken there on the back of a tow-truck?

 

Is the fuel visibly leaking out?