Jaguar xj6 1988 noise from compressor - 1986 Jaguar XJ6

Possibly fuel pump.

Question moved from 'Edge Computers'.

It could be that the compressor itself is failing. It could be the electronic clutch on the unit. It could be the belt slipping if it makes a loud unnatural squealing noise.

That is very low mileage at nearly 13 thousand miles, but as a 1994, the AC may need refrigerant gas.

What kind of noise you are hearing exactly?

if the noise is definately from the front engine timing chain cover area then the first thing i would do is remove the auxillary drive belt/fan belt then start the engine to see if noise is still there? if so the only option is to remove the front engine cover and from remember you may have to remove the cylinder heads also, even remove engine for access\,big job, the engine is normally a bullet proof unit, if the oil has been changed at service advised intervals then the hydraulic chain tensoiner etc should be ok and most noise problems at the front of engine area are caused by. ie. belt tensioner, air con compressor,pas pump etc. so if noise goes when aux belt removed look at the that area. hope this helps.

ac compressors are protected by high pressure and low pressure switches in the system. If the ac compressor will not engage it may be --no gas--too much gas ---blockage in the system--- no cooling fan for the condensor-- burnt out clutch behind the pulley
have an accredited ac specialist check it out.

Isn't there an old trick where soap on the belt can quiet things down ?

That might help you decide whether the belt needs replacement.

Any leak or damage due to ac compressor failure may cause serious damages. For preventive maintenance, keep track of the part's working conditions to prevent compromising the functionality of other engine components. Good thing premium quality factory equivalents to your stock ac compressor are conveniently available for specific vehicle applications. As the part constantly handles the harsh fluids and tough working conditions, structural weaknesses of conventional ac compressor replacements have been addressed in constantly improving the functionality of the part. When looking for the right compressor replacement, putting you money on quality and durable products is advised.

I have a S Type Jaguar which has scrubbed out twice the rear tyres. The noise just keeps getting louder and louder

Could be an A/C problem. Please have the car in to a certified Jaguar re[air place or the Jaguar dealership.
Have you checked to see if the A/C compressor wheel spins?

If this engine has a serpentine belt, then chances are there is a bearing going out in the A/C compressor, idler tensioner, alternator, or other rotating item driven by the belt in the engine compartment.

If the belts are regular V belts, then add them to the list, including that they may be loose as well.