Hi All,

My brother recently purchased a Jag XJ40, 4-litre auto (1991). He didn't notice any problems on the first day he got it, but twice today where he start the car up and it ticks over fine (though the car does judder a bit more than he would expect - timing out perhaps, or maybe sparks need replacing? it does idle at about 750 rpm - is that too low?) but as soon as he shift the box into reverse or drive it stalls. This happens 3 or 4 times and then it sets off fine, and hasn't stalled at traffic lights or anything.

The oil pressure in the car seems fine (usually just over half way on the dial - 5-ish), temps OK and there are no warnings reported by the ECU. He followed the instructions in the manual for checking the gearbox oil level, but couldn't get a very good reading.. that is, after he clean the dipstick and push it in/pull it out again, there's a thin film of oil all the way up the stick (past the "hot" marker), no matter how many times he repeat the measuring process. He will have to have another go at this, but the gearbox seems to work fine after the initial stalling episode.

Two things he is wondering about - when he bought the car the guy at the garage said that when they got it they had to change the battery and they got standard cheap one from their regular supplier.. indeed, the central locking didn't work at first, but it had been sitting for 4-5 weeks at the garage and after he drove it the 100 miles or so home and took it around town a bit the locking suddenly started working and it's worked without fail since. However, do Jags have a heavier duty batteries fitted to them normally, given all the electrics they have in them? If that is the case, is it possible this is the cause of the stalling.

The other thing is that he thought he had read somewhere in a bit of do***entation that came with the car (there was loads of stuff!) that the car would take 95 ot 97 RON unleaded.. but when he was going through the manual he found a bit that said "use only premium unleaded".. isn't "premium unleaded" the 97 RON stuff? could that cause the stalling maybe?

Any ideas on this stalling issue, or for that matter - how to get a clean reading from the auto box dip stick!?


Thanks,
Trevor.

 

As regards your cold stalling, check all leads, plugs, vac lines and connectors. Any codes on the VCM?

Checking your auto fluid.
1 Warm the trans to normal temp, a decent run should do it (10 to 15 miles);
2 Park on level ground.
3 Put car in park and let it run for a few minutes.
4 Now cycle the shifter through all positions on the box (keep your foot on the brake of course).
5 Put it back into park and let it iddle.
6 Pull out dipstick, wipe and replace and immediately check fluid level.

Should be between Min and Max on the Hot side of the stick.

Ignore the Cold side of the dipstick.

Top up if required and recheck by following above procedure.

DO NOT OVERFILL

Fuel unleaded 95 RON = good.

Do not use (even if you can still get it) 97 RON this is leaded and will seriously screw things up.

98 RON unleaded also OK if you are stuck.