I'm beginning this relationship with my 2006 XK8 4.2L with a disadvantage...engine light, "too lean, bank 1 and 2" which I cleared. Using non ethanol gas seemed to help. I later got the light again, sometimes clears sometimes not...has lately after tightening intake manifold brackets, changing filter...now it's back, as the ambient air tempature dropped and now it's back. I do hear, on hard acceleration, a distinct leak, but it leaves and only is for an instant, and gone.

I was on the interstate wringing it out looking for how long I could go without getting the light, went into left lane, and got the light, accelerated, and it straight up FLAMED OUT...DEAD. I let it catch it's breath, started running again, and there's something wrong here. 58,000 miles, seems in great shape otherwise, but a new air filter since the flameout, and the light it on again. I'm a novice, and two med school students, so I"m going to have to fix this myself. I guess I need advice on where to start...PVC?? Sounds too serious, and I don't even know where it is...guess that was it with the 2 screws near the air filter maybe...
Any help appreciated..GSW

 

Maybe it's not a air leak. Have someone put a OBDII scanner on the car and see what the fuel pressure is. This can be seen on the scanner. No pressure gauge needed. Even a PepBoys could do this if you have no scanner yourself.

I'm not saying this is the fix, but it's one of several things to checkout. You already made sure the air intake ducting is good from the filter to the intake.........I assume.

 

Good idea, and thanks. I was thinking about the fuel filter, fuel pressure, etc. as another approach, but I do hear a squeak occasionally under higher throttle, low speed when it shifts, coming from under the hood somewhere. Just a little squeek, so it may not be related. Fuel pressure is possible, as it did quit at high speed, high demand on accelerator. Seems like it would be pretty obvious, but let's see if the fuel pressure is normal and replace the filter maybe....thanks for the reply. I have a basic scanner, maybe it would read it. Not experienced with this though.

 

Gary,

I've moved your thread from XK/XKR 2006 onwards to XK8/XKR 1996 - 2006 forum.

Members here with the same model as you have will be able to offer further advice.

Graham

 

I have had a similar experience with stalling at speed because of a lean condition. My case turned out to be a MAF problem where the amount of air was being misrepresented.

Check the fuel trims in a few conditions, idle in P, idle in D and cruising down the highway.

Small leaks usually show up at idle but get washed out by the total amount of air being consumed when moving.

If the trims are ok at idle, but high at speed you could have a problem with the EGR or Evap system. These only come on when the car is moving.

If it is high across the board, it might be the MAF or fuel pressure like you say. Your year has an returnless fuel system and a pressure sensor on the rail. Should read 55psi on OBD and be pretty stable under all load conditions. If it droops more than a few psi, you could have a supply problem.

 

If your 'basic' scanner does not show FPR or fuel pressure, then I 'think' a PepBoys or Autozone might take a look for FREE with their scanner. Like the man said above, the pressure should be what he says.

I've a scanner that I can see it on (fuel pressure) and also bought a thing called a ScanGuage and I can read it there also. That ScanGauge is a small digital meter that you can plug into your OBDII port and mount just about anywhere and you can read most anything like water temp, fuel pressure, mph, tps etc while driving along. Did cost about 80 buck though. A toy, not a neccessity (sp?).

 

Also, please post the actual fault codes (P????) here for the best advice. The descriptions from the code reader, the internet or a lookup table may not always be accurate for your specific car.

 

The squeak you mention during shifts on occasion is likely the common transmission bark, which is benign, but can be remedied with some Jaguar magic elixir additive. Search the forum for transmission bark, plenty of info.