I appreciate any help here. My Manual 03 X-Type has run perfectly for 90,000m, however, after a recent 100 mile highway trip and just before pulling into my driveway the car felt fuel starved, the MIL started blinking, then steady and no power when accelerator pressed. MY OBD II produced codes P0300, P0304, PO354 and PO1316. I changed the plugs to Iridium, replace Coil for 4, checked the wires, checked for vacuum leaks and re-started. There was oil in the plug wells 1,2 and 4 that I cleaned out. I did not change the valve cover gaskets. The Car starts immediately, idles OK but same fuel starvation problem. The OBD II reports a steady HPGA 358 , however, it drops to HPGA 200 immediately on acceleration. I continue to get DTC P0300, P0302, P0303, P0304, P0305, P1314 & P1316. I seem to get adequate exhaust pressure, however, the MIL light was on for an Cat efficiency months ago but the light went out by itself. Before I change the Fuel Pump or Convertor can anyone lead me to a single focus? Thank-you for any feedback.

 

Here are the codes.

http://www.coffeeshopmenus.org/400OBDII_2002MY.pdf

What kind of shape is your battery in? I notice several mention battery voltage.

A bad battery can cause almost any sensor to send invalid error codes.

 

Bud Tender, My battery was replaced during this winter,, 4 months ago and tests good.

 

pencil base, you will want to look at the wiring harness for the coils. There is a common ground wire point that all the coils use. It may be that you have a little bit of corrosion built up on the ring lugs and that is causing what you are seeing. Granted, not to question the plugs that you put in, but from what you are describing, it sounds like either you have the wrong gap or are trying to use a multi-point spark plug (plugs like the Splitfire or the Bosch +4's). The multi-point spark plugs do not play well with our engines and have been known to cause issues.

I think your original problem was oil in the #4 plug well leading to a misfire (the P0304 code) and that then allowed the P0300 code to also come in as there were some gases left over making the computer think other cylinders were randomly misfiring. This would then lead to the P0354/P1316 codes. But, since you changed the plugs and things got dramatically different, I go back to what was changed. This would point me at the spark plugs now being the source of your problem.

 

Chris, Thank-you for the advice. I just remembered a similar problem that I had with a 2001 De ville that turned out to be G001,, the ground from the engine to the chassis

 

Flashing MIL = cat-damaging misfires. Fix fast or change cat(s) as well.

 

JagV8, Thank-you for the advice. I will endeavor to list the vehicle.