Can anybody help with the following. I have an XK8 (2000) less than 35k miles. When I first got the car there was a Restricted Performance Message. Went to Jaguar the updated software cleared the code and engine light. After a few hundred miles, started getting a ACS and Restricted Performance warnings. Each would go away after a few seconds to a few minutes. Another few hundred miles, started getting ACS, Restricted Performance and Coolant level low. Checked coolant it was fine. Again warning would go off after a few minutes. During these events the car runs fine.

Today I get the Restricted Performance, ACS, Engine Coolant and a new one Engine Fail Safe. This time there was a marked change in vehicle. Press the gas pedal and go about 3 miles an hour. Pulled off the road, shut the car off removed the keys. Put the keys back in the ignition, started the car, all warnings went off and the car ran fine for 3 or 4 miles. Again all the warnings come back on and car runs like its got no power. Pulled off, restarted the car everything fine. This repeated a couple time before I could get home.

Any ideas, besides I am screwed?

 

Welcome to the forum.

First thing you need to do is get the fault codes read, otherwise all anyone will be doing is guessing.

Some chain autoparts stores will do it for free, or you can buy an inexpensive code reader that will at least read the standard engine fault codes.

If you come back here and report the codes, we can try to help you.

 

Yes, get the codes read, also check out this thread: https://www.jaguarforums.com/forum/x...ailable-42069/

 

Welcome to the forum!

I have the same year XK8 and have had all the issues you describe at one point or another. You are probably just seeing the effects of some worn out parts due mostly to age. It looks (and feels) worse than it is.

Restricted Performance is a first layer of engine protection that comes on when it senses something isn't operating correctly. You won't notice an effect unless you are pertty high up in the RPM range - and sometimes not then even. RP will come and go depending on the fault code triggering it.

Engine Failsafe is the second layer of protection and you'll notice it easily - you are restricted to low RPM and it feels like the gas pedal isn't connected to the engine anymore. Depending on the cause, a restart often clears it -- temporarily.

Get the codes and we can set you straight.

 

There was a problem with the INTSTPK Back Plate crushing the solder on the circuit board causing a CAN failure. It has been a long time since then but it could still be a fault???

Here is the old Service Action.

bob gauff

 

Thanks for all the replies. Took the car to Jaguar. They looked at the codes and claim the problem is the throttle body. Quoted a cost of $3,500.

Any suggestions? Thanks in advance.

 

Go to to an independent Jaguar mechanic. If he confirms the thrrottle body diagnosis, then have him use a rebuilt throttle body or have yours rebuilt. You do not need to replace with new. Diagnosis and replacement should be roughly 2 hours of labor.

All told this should cost you considerably less than half of what the dealer quoted.

 

For $3500 I will replace the throttle body with good used parts for several years, parts and labor over and over!!!!!!!!!!!!!!!!!!!!!!!!

car-part.com

and you will save alot of money!!

bob gauff

 

order a used tp

 

Rebuild! $350.00 US. I did mine and it cleared up the Failsafe immediately. Don't buy used junk, rebuild your current unit. ATE in Tennessee did mine in a couple of days. Add a $9.00 gasket and $0.50 worth of coilant hose and you are good to go...

 

Regarding the ACS/Restricted Performance issue consider a rebuild of your ACS module. $150.00 and 1/2 hour of time fixed mine for good. Try Module Masters in Idaho. I was satisfied, very professional.