1984 XJ6 sedan, with 4.2 L engine, car starts very well, runs and goes through the normal 3 speeds changes, and then as the temp gets higher, starts to stall, give it gas and just wants to die, any ideas.

 

If it's carbuerated, the choke plate may be sticking. I don't know about Jag, but my '85 Dodge is carbuerated.

If not then I would suspect a temp sensor gone bad.

 

Not carbureted, fuel injected engine, I have checked the temp sensor, not the issue. thinking more on the fuel mixture ?? or oxygen sensor ? or leaking fuel injector ? just wanted to check if somebody has this kind of issue and what was their solution.

 

Without knowing the history of the car it's impossible to say what's wrong with it. How long has it been running bad? How many miles do you have? Is the catalytic convertor original? Does the exhaust smell bad? Do you get a check engine light? Have you replaced the throttle position sensor? How much experience do you have with early fuel injection? A lot of things happen when the computer sees the car is up to temp. Until then it runs on internal tables and only uses the oxygen sensor at operating temp. It also probably runs a check on EGR like my GM's do.

I've always replaced the sensors every hundred thousand miles so I don't have a problem like that. As well as belts and hoses and bushings. Normal wear stuff. Put in a new set of injectors. Clean the throttle body and intake system, they get carboned up. Make sure the intake isn't leaking, a leak can cause what your having if it's big enough. I'll try to help if you wish or I can go away.

 

Welcome to the forum jtonyzap,

I've moved your question from General Tech Help to XJ6 & XJ12 Series I, II & III forum. Members here with the same model will be able to help.

Please follow this link New Member Area - Intro a MUST - Jaguar Forums - Jaguar Enthusiasts Forum to the New Member Area - Intro a MUST forum and post some information about yourself and your vehicle for all members to see. In return you'll get a proper welcome and some useful advice about posting to the forum.

Graham

 

Hmmm.

An easy jumping-off point:

Is the ductwork between the AFM and the throttle body in good shape, no leaks?

Cheers
DD