Hello,


Im new to the forums and I had a 1991 XJ6 Sovereign. The temperature gauge keeps going up and down. The car does not shake until the needle is pointing at the red.

Can anyone help with suggestions or advice?


Thanks,
Ralph

 

Welcome,
You mean oil pressure gauge ,right ? If so yes they do all work like that . As you push the throttle down , the gauge moves up to the middle or when idling or stand still it is just above the red markings . However let's say you are in N or P and while idling you will see that it just above the red (to the left side ) but as soon as you give a throttle the gauge will be loving up to the middle while in standing still

 

Yikes!! First off, water temp gauge not oil temp.

OK check your coolant levels and oil levels. (when did you last change the oil and filter?)

What does your oil pressure gauge read?

Any mayonnaise in the oil? Oil in the coolant?

Does it still go into the red with the Aircon set to manual? Could be a broken secondary Aircon fan.

Is your main fan belt good, and tight enough?

Check thermostat for operation, does the bottom radiator hose get hot? If yes then coolant is flowing, if no then suspect thermostat.

Are you losing coolant, requiring regular top-ups?

One thing is that these cars should never get into the red. If it does start to get there then switch it off and let it cool down, before it starts to shake!!

I'm hoping that you have not let it go too far and have destroyed a head gasket, or head.

If you are low on coolant when it gets too hot, then let it cool down for a few hours before adding cold coolant, you don't want to risk cracking something.

 

Yes, it is the oil pressure gauge that goes to left and right. Sorry for the misunderstanding. So, all jags do this right? I was concern that it was going to be a big problem. Thanks for all of your help guys!

 

Check your oil level, pronto.

If you are seeing movement on the oil gauge some is normal. It will drop when hot at idle speed and should almost imediately rise when you raise the engine revs.

An oil and filter change may give you some help. Go with 20/50 oil and a good filter. After an oil service my 92 (hot) will idle at around 4bar and rise to about 6bar when moving. 150,000 miles.

The car should not be shaking, what do your idle revs drop to when this happens?

 

When the Car is cold it works fine but the engine warms up and it starts to go left when I'm completely stopped but like you said when I rev the engine to go then the needle starts to go right imediately.

When the needle goes right it goes all the way to touch the red. Is there a way for oil pressure to escape that might be causing this?

Also my VCM message says Fail PAD? Are these the brakes that need to be replaced?

 

Hi RufflesJag

Yes, fail PAD is almost certainly the pad wear indicator - check them out, it's not hard to do, but wheels have to come off , and a little mirror makes checking easier.

Oil pressure gauge reading was always a worry on Jaguars from the 1950s onwards, so to make it easy for owners, they eventually took it out after your model of car !! It could be general wear and tear, but the culprit is generally the pressure transmitter which detects the pressure on the oil gallery. These gradually die, and the dying results in lower pressure indication, never a higher one. For what its worth, my old 1980 XJ6 4.2 always had a low reading on tick-over, but I don't think it actually had a red sector. You could try a thicker oil than the paraffin-like stuff they put in now, (as suggested by Translator). I never had any problems, as pressure was OK when revs went up to normal driving

 

I will take Translator's and your advice. I'm also going to change the rear brake pads and rotors. I've been hearing the sensor for about a month now! lol