1989 Jaguar XJS idle

Tiny
CASAMONTES
  • MEMBER
  • 1989 JAGUAR XJS
  • V12
  • 2WD
  • AUTOMATIC
  • 84,000 MILES
Cold start at 1200 rpm when warms up, idle fluxuates rapidly from 700 to 1200 rpm, after about 5 min. Settles down to about 800 rpm, also tempature gauge shoots all the way up whithin 12 min running from a cold start, can you help me solve? I will donate.
Sunday, May 11th, 2008 AT 2:45 PM

1 Reply

Tiny
GPACK
  • MEMBER
  • 1 POST
Hi,

I had the exact same problem on my 1992 xjs 12 cyl. At startup, the rpm would surge up and down for 5-8 minutes then it would stabilize once warmed up. When I opened the hood, it was like that engine was alive! Anyway, it was the auxiliary air valve that needed replacement. That part cost me 445 and 2 hours of labor. I had recently bought the car and the previous owner lived with this surging for years. I had a MAJOR tune-up and fixing of all leaks, etc. That cost over 4000. This aux. Air valve was the most costly part of the overhaul. (This was done in NYC)

Hope that helps because once they were done with my car, it was like new.

Good Luck,
Gretchen
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Monday, June 9th, 2008 AT 6:08 PM

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