Well it's been over a year since I said goodbye to my 1987 xj-s and yesterday I relapsed into the jag insanity and bought a black 1988 xj-s coupe in good order with only 65k miles. Drove it 300 miles home. Fifth xj-s so I know what I'm in for and she already has some quirks that I need some help on:

***A strange faint "hissing" noise coming from inside the dash when the car's running only when the accelerator pedal is depressed 10%-30% down- let off the gas it goes away, give it some more and it goes away too. hmmm leaky vacuum line?

***oil pressure is a bit low after the car warms up. was cruising home yesterday at about 2700 rpm and the oil pressure was fluctuating from 20-26ish ft/lb. Thinking maybe it has the wrong oil in it?? Oil change tomorrow we'll see what happens..

***what is the best method for adjusting the idle speed? When stopped hot it's only idling at about 400rpm and stumbling like its about to stall. other than that she runs smooth as silk.

***Could anyone remind me how to bleed the cooling system properly?

*** The radio says code and the code is missing. Am I going to have to pay the jaguar dealership an arm and a leg to look it up?

That's all for now. Any advice is always appreciated, it's good to be back Jaguar forums!

 

V12 cooling system bleeding:

There are different opinions on what works for filling and bleeding but most owners follow the same basic procedure. Here's the process I used on my '88 XJS V12 and a few others. It's not difficult, just messy.

Elevate the front of the car about 8" and then elevate the left front another 2-3" beyond that. Set the climate control for max heat so the heater valve opens.

Remove the bleeder plug from the left radiator tank. You'll see an access hole in the radiator upper mounting panel. The plug is some arcane size but you'll find something in your toolbox that fits.

Remove the caps from the expansion/header tank and from the filler pipe at the front of the engine....up there by the A/C compressor.

Add coolant/water to via the filler pipe until it reaches the bottom of the pipe. Start engine, set heater control to max heat. Let it run at idle until it warms up. Peek inside the filler pipe every minute or so and top up as needed.

When the engine gets warm increase the idle to about 1000-1200 rpm (a helper is helpful here...or just wedge a little something in the throttle linkage to hold it slightly open for a high idle.

Let 'er run and run. Give the upper radiator hoses a few squeezes now and again. Keep checking your coolant level in the filler pipe and top off as needed. Eventually you'll see some coolant coming out of the bleeder. That's good. Wait a while longer and (hopefully) you'll see coolant *really* pouring out of the bleeder. (How much? It's one of those "you'll know it when you see it" things..very messy)

When it's *really* pouring out of the bleeder hole, put the plug back in. Wear some gloves so you don't get scalded. If you can't get the plug back in thru all the gushing, shut off the engine and do it....but I like to leave the engine running if I can. Not worth getting burned, though.

Top off the coolant in the filler pipe...I go right to the top but some fill just to the bottom of the neck... add a quart or so to the expansion tank if you suspect it might be low, button everything up, and yer off to the races. If you've overfilled the excess will be pushed into the atmospheric tank mounted inside the fenderwell. If you've *really* overfilled the excess will exit the atmospheric tank and end up on the ground.

Lower the car and clean the driveway :-)

Cheers
DD

 

Yes, it does sound like a vacuum leak




Unless you're in sub freezing conditions try 20/50 and see what happens.

As you probably know, though, the XJS gauges are often flakely





The adjustment screw (looks like a bolt, really) is in the AAV (Aux Air Valve), roughly at the very rear of, and jsust below, the LH cam cover.



Any books and papers with the car? If so, the code might be written down somewhere or the original ID Card might still be there. When these cars were new some dealers marked the code in an inconspicuous location under the hood or on the underside of the trunk lid

Otherwise, yes, call a dealer with your VIN and they should be able to get the code. At least that's always been the case in the past. One wonders how long Jaguar will archive this info.

Cheers
DD

 

clean out the filter and PCV, the can very negatively affect oil pressure

 

Congrats.... I love the coupes and the enjoyment of driving them.

 

Welcome back! Personally I would never pay the dealer to unlock the code (unless shooting for 100% OEM). Throw in a non flashy Blaupunkt, Nakamichi, or vintage Alpine and call it a day. Also, can't believe I even have to say this...

 

Here she is but despite how the picture looks the paint is very faded and I'm having her repainted (black) down to bare metal scheduled at the beginning of June (will post pics of course).

Speaking of "her" I still haven't thought of a name yet.. Any ideas?

 

Looks beautiful in the photo! How's the interior?