Following my earlier problems with poor starting, which cleared itself up, I now have a possibly related problem.

When fully warmed up it will sometimes pull to hard ie uphill at 40mph without touching the throttle.

I also had a single case of restricted performance. Stoped and restarted and it cleared but it then had the first occurance of the above over power issue.

I have cleanned out the throttle body, inlet,
breather pipes and mass airflow meter and
there are no faults on the torque

 

Is more power really a bad thing? Just a hunch, but maybe cleaning everything up could've freed up some of the lost horses.

 

there are no faults on the torque
Do you mean no OBD Codes ?

If you are using the Torque app look at throttle % with foot off + WOT;
.

If this doesn't give 0 + 100% check your throttle cable and do the throttle learning in here https://www.jaguarforums.com/forum/x...nect-74146/HOW

Also leave torque running and see what throttle opening it records when you get the foot-off overspeed problem - something in the throttle line may just be sticking.

 

Could it be the cruise control kicking in?

 

Thanks for all your responces.

Today I have gone into restricted performance 4 times. This time I used the torque app to get an error code P1229.

Can anyone advise what this means?

 

Hi Smoggy,
P1229 Intercooler Pump Driver Fault, is what the Jag specific code sheet says.
Also found this,


P1229 Throttle motor control circuit

malfunction

Throttle motor disconnected

Throttle motor to ECM drive

circuits; short circuit or open

circuit

ECM ground circuit fault(s)

(EM80-04, 05, 54)

Throttle motor failure

Throttle body failure

FOr throttle motor to ECM circuit tests, GO to


Pinpoint Test X. For throttle body, motor relay


tests,


REFER to: Fuel Charging and Controls (303-04 Fuel



Charging and Controls, Diagnosis and Testing).
Hope this helps,

 

When I look up the DTC List for 1999, 2000, 2001, it says P1229 is Throttle Control Circuit Malfunction.

A Intercooler Pump Driver Fault would only apply to a XKR. The Intercooler fault is P1474.

 

Thanks for the responces on P1229.

I also did a google search and it brought me back to this forum and this thread https://www.jaguarforums.com/forum/x...roblems-60386/. Which also includes a link to a TSB on the issue.

I have cleaned the electrical connection and after 2 drives today all appears to be working correctly.

 

Its Back again, but again cured, in the short term by a re clean.

I decided to bite the bullet and carry out the change to gold terminals as discribed in the TSB.

The Jag parts are 6 inches of wire with a gold plated connector.

They are £23.50 each + 20% tax and you need 4. The Jag dealer parts man said he'ld never seen such a rip off in his life.

Now waiting to find a salvaged connector from a post 2001.

regards

 

Smoggy had the same problem, the connection would loosen up and set a code. Cleaned mine add diaelectric grease, and installed a small wire tie around the connection. It's been 6 months and over 5 grand on the clock. Cost .00 left overs. Hope it helps Jim