Welcome to the forum Mjames1068,

I've moved your question from General Tech Help to XJ40 forum. Members here with the same model will be able to help.

Please follow this link New Member Area - Intro a MUST - Jaguar Forums - Jaguar Enthusiasts Forum to the New Member Area - Intro a MUST forum and post some information about yourself and your vehicle for all members to see. In return you'll get a proper welcome and some useful advice about posting to the forum.

Graham

 

Hi Mjames,

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

If I understand your description, it sounds as though your car went into Limp Home Mode (LHM), which locks the transmission in 3rd gear. In our 1993 XJ40, the most common cause of LHM was oil contamination of the electrical connector of the throttle position sensor (TPS). The connector is mounted to a bracket on the intake manifold elbow just to the left of the throttle body. Separate the two halves, flush them with zero-residue electrical contact cleaner spray (available at most auto parts stores), allow to dry, then reconnect.

The TPS itself is mounted on the underside of the throttle body, and over time, oil drawn into the throttle via the crankcase breathing system works its way down the throttle butterfly valve shaft into the TPS, where it gunks up the resistive traces and wiper (the TPS is a potentiometer, or type of variable resistor).

I would recommend you start by cleaning the TPS electrical connector and also checking the Vehicle Condition Monitor (VCM) for any stored diagnostic trouble codes (DTCs). To do so, turn the key to position II (ON or RUN) but do not crank the engine. Press and release the VCM button on the trip computer to the right of the steering wheel. Now watch for any message to appear in the small window below the speedometer where the odometer/mileage display normally appears. DTCs appear in the form of Fuel Fault or FF and a two-digit number, such as FF22 or Fuel Fault 89. Write down any message exactly as it appears and report it here and we'll try to help.

Cheers,

Don

 

I recommend you start by cleaning the tps electrical connector.