Just got the same car, sitting since 09, so far FPR is the only thing that hasn't been regular maintenance. Still after tune up it will idle VERY ruff like it wants to stall but doesn't. Will drive just fine. Stinky smoke coming out the pipes. I'm going to do the o2 sensor and ICV this week. Any other suggestions?

 

Clean out the intake plumbing and throttle body butterfly

 

Hi Anubis,

Welcome to the Jaguar Forums! It's great to have you with us.

I have moved your posts to a new thread so we can focus on your specific issues (the other thread to which you posted had had no activity for years).

The first thing I would recommend is that you check the Vehicle Condition Monitor for any stored Diagnostic Trouble Codes (DTCs). To check, turn the key to Position II (Ignition On) but do not start the engine. Press and release the VCM button on the trip computer to the right of the steering wheel. Now watch for a message to appear in the small window below the speedometer where the odometer/mileage is usually displayed.

If any codes are stored, they will be in the form of "FF" or "Fuel Fault" followed by a number. Write down anything that is displayed and post it here so we can help.

One test of the FPR is to pull the vacuum hose, turn the key to position II or even crank the engine briefly, then check for signs of wet fuel at the FPR vacuum hose fitting. If you see any, the diaphragm has failed and raw fuel is being inhaled into the intake manifold and contributing to rich running.

You can test the O2 sensor's performance by back-probing its electrical connector.

There is a wealth of information, including factory service documentation, available from the 'HOW TO' quick links thread on the home page of this XJ40 forum, and at websites such as jagrepair.com.

You can remove the IACV, disconnect the stepper motor and clean all the carbon from the valve and the stepper motor pintle. I use a small wire brush on the pintle and a battery terminal brush in the ports of the valve body, along with a suitable solvent (whatever's handy, like brake cleaner or throttle body cleaner).

There are plenty of other possible causes of can you please tell us what was done in the tuneup?

Also, please visit the https://www.jaguarforums.com/forum/n...-intro-must-5/ and post a required introduction so we can learn something about you and your Jaguar and give you a proper welcome.

Cheers,

Don