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Mike, Technician
Category: Car
Satisfied Customers: 39198
Experience:  Tech Expert
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I drive a 1988 jaguar xjs 5.3 convertible,the car starts

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hi I drive a 1988 jaguar xjs 5.3 convertible,the car starts fine but when the engine is up to running temperature the revs seem to go up and down on tickover until it cuts out.thanks from Don
Hello and Welcome - My name is ***** ***** Im happy to help/ advise.So do you get any fault lights on at all when this happens..?Have you replaced any parts at all - any work other than what you have said.?Rgds, MIKE...........................
Customer: replied 2 years ago.
hi thanks for getting back to me,there are no warning lights on, when driving I can give it some throttle and the car pulls as normal, its just on idle that the car stalls, the revs fluctuate up and down
Hello again,
Thank you for your reply / info.
Ok - I note you have checked the vac / air pipes etc - so thats good.. Be sure that there are no loose pipes - no persishing etc - no tiny holes that become bigger with engine movement.
Check the TB - throttle body - check its tight on its mount - and listen for any air being sucked... at the base gasket.
A good idea too is to use a length of hose as a stethoscope - listen around all the areas of the engine where there are pipes / joints - gaskets etc - inc inlet manifold - for air noises. Any unmetered air being sucked in will cause what you have.
If all is truly well then the usual fault is with the idle control on the throttle body.
You can try a thorough clean of the throttle body and idle control unit on it - that will usually cure this as opposed to having to replace the unit - that is a last resort.
Let me know how you go..and / or let me know if you need anything further on this..
~>>~~>>~ Meanwhile now at this point- Please do click on the "Exc / Ok rating" for me at this time.. "Thank you" in advance for that .
.. Note that you can get back to me anytime at all after doing the rating - it doesn't close you out --
Best Rgds, MIKE
Customer: replied 2 years ago.
Thanks I'll have a look,however I've checked the throttle linkage, thanks
Hello again Don - Your'e very welcome... Per the way justanswer works, I do just need you to click on the "Ok/ Exc ratings" for me at this point - and I thank you for that.Again, you can get back to me anytime if needed.Kind Rgds, MIKE.
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Customer: replied 2 years ago.
hi Mike after a good poke around all the vacuum pipes, I found that the pipe coming out of the right hand filter box that then went to the injection manifold was indeed cracked, I fitted a new 3.5mm pipe and i'm pleased to say the cars is now running smoothly again.Thanks for all your advice and pointing in the right direction yours Don