New member introduction, sadly already with technical problems

[Yann Lautrédou]

Hi all,

My name's Yann, been a reader of the forum for a while now, appreciating the help i could find here and decided to become a full contributing member.

I'm from France and own a 2001 986 S RHD boxster, with juste over 60K miles on it. It was running beautifully until last week, when 50 miles after changing spark plugs and coils, the CEL went on first flashing, then just on.

The engine kept running but acceleration was rough making the car really shaky , but the engine had no problem cruising. Being not far from my place i kept going for 10 minutes, thinking one of the coil went off.

A quick read of the error codes gave me "Misfire in cylinder 6" so after letting the car cool down, i went to check if the coil was well in place. It was... so i wondered if maybe i didn't put enough torque when putting the new spark plugs in. I proceded to take off every coil and spark plugs, checking the torque when screwing the plugs, putting them back in, checking the connections to the coil. everything was fine. Or so i thought.

When i try to start the car, the fuel pump won't start and just make 3 brief click sounds, the engine try to start, but it's like trying to start with no gas. And yes, there is gas in the tank :)

Re-plugging the diagnostic tool, the DME section gives me the 6 error codes P1225 to P1230 "Fuel injector below limit on cylinder x" (x being 1 ot 6, obviously)

Could I be unlucky and have a faulty fuel pump on top of my misfire problem or am i looking in the wrong direction ? Can a misfire cause heavy damage to the engine and/or the fuel injection circuit ?

Any help appreciated, sorry if this problem has been adressed before, researching for the error code didn't helped...

[JFP in PA]

P1225-1230 are all "short to ground in wiring" codes for the fuel injectors by cylinder numbers, so I am not convinced it is a fuel pump issue.

You can quickly check the fuel pump by following the factory test procedure for correct pressure and delivery volume by connecting a test gauge to the test port on the fuel rail; but the codes are going to require running electrical tests on the injectors and the injection wiring looking for a short to ground somewhere in the system...........

[Yann Lautrédou]

Thanks for your help, yes, electrical testing is next on the list, despite how i hate it, but i wondered if having a ground suddently on all cylinders wasn't a faulty pump symptom. I'll run more tests next week end.

[JFP in PA]

The injector and the fuel pump are on different electrical circuits, if the pump shorts out, it has no electrical effect on any of the injectors. You have an issue on the injector circuit, not the pump circuit.

[Yann Lautrédou]

Ok, thanks a lot.

[Yann Lautrédou]

Finally saw the end of it today, one of the coil i replaced was causing a short circuit (no visual damage on it though), replaced it, everything runs fine.