Hi all

Have noticed on a few recent trips that my 2003 XK8 seems like it has a surge when driving at constant speed(60mph-70mph). Also noticed that it tends to lope or kinda miss a bit on cold starts till warms up. Today i took it for a nice drive around 80 miles and on open roads could feel very slight surges when holding throttle steady.

Came to the forum and most attributed it to faulty/dirty injector/s. Went to supply house for some injector cleaner and on the way home my check engine light came on. Scanned with obd 2 and pulled a PO 193 code. Cleared code and added the injector cleaner. All seemed ok but on return trip after about 30 minutes of driving i got the engine light again and it scanned the same code PO193.

Bad fuel rail sensor/connector?
Dirty/faulty injector?

Did a visual of all sensors on top and seem to be ok. Having a hard time finding location for fuel rail sensor. Any thoughts or suggestions would be greatly appreciated as always thanks in advance.

Cheers!

Andrew

 

JTIS gives this:


Does your OBD scanner allow you to read fuel pressure? Would help if you could post what pressure you're getting.

Fuel pressure sensor is on the front of the right hand fuel rail (when viewed from the rear of the car). Has a vacuum hose and an electrical connector on it.

 

I replaced mine a few weeks back as it was occasionally leaking. You have to take the plastic engine cover off, hen you can see the rail. The sensor is at the end. Replacing it is a 10 min job. 2 screws, a connector and a vacuum line. A bit over $50 at rock auto.

As already pointed out, fuel pressure is available over OBDII on the later XK8/Rs. A cheap ELM327 can get it, and a phone app like TorquePro can show it real-time. Should read about 55 psi.

Best of luck, keep us posted.

 

Well was able to read fuel rail pressure today with my scan tool. I did it on a cold start up and I am getting readings of 378-381k pretty steady. Did not notice any large fluctuations at any time.

 

did a conversion to psi. Its 54.8 to 55.2 psi. That seems normal?

 

FMertz thanks for you suggestion for Rock Auto. Sensor was $58.00 shipped. I went ahead and ordered it. From all I have read and researched this should sort it out I'll let you know how it works out.

Just have to say that without this forum owning a Jag wouldn't be a lot of fun.

 

Thanks guys for helping out. Got the new fuel rail sensor in today and the problems with surging, etc... are gone. $50 fixes I can live with any day.

 

Glad it worked out for you. Thanks for the update.