could someone tell me what fuel 16/ fail 16 on my 1992 XJ6 means? I have replaced fuel pump and filter and still will not start Thank you

 

Hi Harold:
This will get you started:

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Offhand I could not tell you whether that alone would cause a non-start. Somebody with experience will undoubtedly chime in. There are, of course, a number of other things that might…

Cheers,
Scott

 

Check your air temperature sensor and its connector.
The ATS is located on the intake elbow.

 

Hi Harold,

As Roger has mentioned, FF 16 indicates that the Air Temperature Sensor, Ambient Air Temperature Sensor or Intake Air Temperature Sensor (IATS) is not in operating range (the manuals use all three names for the same sensor). It could be the sensor itself, or a problem with its electrical circuit such as a loose or corroded electrical connector or a broken or shorted wire in the harness. Sometimes though, codes like this are triggered by low battery voltage and/or corrosion on the ground point associated with a given sensor (in the case of the IATS, it is grounded through the Engine Control Module (ECM)). You can test for 5V across the two terminals of the IATS electrical connector with the key turned to Position II.

Photo 4 in the album at the link below shows the location of the IATS, and Photo 9 shows the sensor removed from the intake elbow:

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I don't know if FF16 can prevent the engine from starting, but my instinct is that it shouldn't. The IATS signal has an influence on the ECM's choice of ignition timing map, but its signal is one of the timing correction factors, not a primary determinant of ignition timing strategy (the primary signals come from the MAF and Crankshaft Position Sensor (CPS)). The IATS signal is also referenced for the operation of the Crankcase Breather System, but loss of that function shouldn't cause a no-start either (at least I don't think so).

Before we go down the long list of issues that can contribute to no-start conditions, maybe the answers to these questions will help narrow things down:

1. When you crank the engine, does the tachometer read about 200 rpm, or does it read 0 rpm? 0 rpm is a classic symptom of failure of the Crankshaft Position Sensor (CPS), a very common cause of no-start.

2. Can you test the battery voltage while cranking the engine? If the voltage falls much below 11V, the ECM won't trigger the ignition to fire. Many meters can't react quickly enough to accurately tell you how low a battery is sagging while cranking, so it's a good idea to have the battery load tested on a high-quality test system.

3. What prompted you to replace the fuel pump and filter? Did you determine the pump had failed? Do you know if the Fuel Pump Relay and Oxygen Sensor Heater Relay are working properly?

Please let us know and we'll go from there.

P.S. If you don't have the following references, I highly recommend them:

Haynes XJ40 Service Manual (download from the XJ40 'HOW TO' quick links thread on the home page of this XJ40 forum)

XJ40 1992-94 Service Manual DVD (purchase from the Jaguar Daimler Heritage Trust)
http://www.jaguarheritage.com/xjr-xjr-s-jhm1152

XJ40 Supplementary Model & Service Information DVD (which includes Electrical Schematics) (also from JDHT)
http://www.jaguarheritage.com/supple...mation-jhm1130

Cheers,

Don