hey guys whats going on this is my first post and its about my first jag well when i first got her she started up right away after a year of sitting, first turn of the key i was amazed, when i bought her she would start up all the time then one night (prom night) i left her at a friends and went to get her in the morning when i went to get her she wouldnt start i was clueless since I had no time to deal with it (had to catch a flight to europe) i towed it home. when i got home after my trip i tested her out and she fired right up, she worked for a couple days fine, then she refused to start while cold. i thought the fuel pump went out but to make sure i bought a can of quick start i sprayed some in the intake and she started. after i let her warm up i turned her off and she would turn right back on again, every single time. but over night or a extended period time of not driving her she would not start again. i dont get why she wont start when the engine is cold, the idle control valve has been changed and i also bought a brand new battery. can anyone out there help me out? by the way its a 1997 xj6 4.0L inline six. thanks again guys and im extremely excited to be part of the community.

 

Maybe she's jealous.
Maybe she thinks you are driving another car behind her back.
When you get into her on cold mornings, do you smell of Chevrolet or Nissan?
Can she see your Dodge keyring?
Jaguars are sensitive about these things, you know.
The truth is, I'm new to Jaguars myself and I have no idea what the problem might be but with your post back up at the top, with a bit of luck a smart person may see it and be able to supply the answer.
Cheers,
Steve

 

Wold guess is the CKPS, the crank position sensor on the front of the crankshaft. This is one of the few parts that changing iwithout certain dianosis is cost effective.

 

OK,

First and foremost, WELCOME.

The X300 is a fickle beast if upset. I was told back in 1968 when I got my first Jaguar (MK7M) that they are ALL female and MUST be treated as such, nothings changed.

My list of things to do/check are:
IN NO PARTICULAR ORDER

Spark plugs. A new set will do NO harm.

CTS (coolant temp sensor) in the thermostrat housing. This is NOT high on my list but mine reeked havoc at times and mainly when cold, mmmmm.

The fuel is "draining back" to the tank. It happens, so that is why ALL cars crank a little prior to firing when cold. The pump has to recharge the system. Some cars are worse than others.

The "cam angle sensor", which is the thingy in the hole on the RH side of the engine that once had a distributor fitted in it. This thing can be refitted by someone NOT in the know, and NOT be timed correctly, which in itself is sort of OK, as the Nippon Denso engine management system can work it out MOST times, but NOT always, so to retime this is a GOOD idea in my opinion.

There will be LOTS of things suggested, and none of them bad ideas, but I always look at the simple things first, as it usually incurs little $$ and can fix things.

The fuel pump has an average life of about 100k miles, and this is from industry specs NOT Jaguar or me, and mine is getting noisy at 173000kms, so it is next on the list. The XJ-S has had the pump swapped at about each 140k kms and is now on pump #3.

 

iv changed the plugs cause i had it emissions tested just a couple days ago so i changed it before. but i think ill start off with the coolant temp sensor? then the crank angle sensor. ill let you guys know right away, oh ya i also changed the fuel filter and fuel pump.