My 2003 XK8 has a new bad trick. Every time it rains, the car won't start. It cranks over like there is either no spark or no gas. No codes either. The car sits outside under a cover on rainy days. Wait 24 hours and it starts right up.
Ideas? Thanks

 

Have you looked for water in the spare tire trunk well?

I would also check the air intake hose between the air filter box and the throttle body for cracks and splits....

It may prove to be a more obscure problem with your fuel delivery system but I would start by having a look at those two possibilities....

 

In the good old days (points and carburetors) guys with old cars would keep a can of silicone spray around to dry off the ignition wiring on really wet days. The more I've learned about electronics, the less I'd ever want to use silicone.

Is there a job harmful wire dry spray out there that anyone's used? I ask because this may help Pantera, and trust I'd like to learn too.

John

 

Hmm, check the "bins", driver side where the brake booster is as well as the passenger side. Supposedly, some water can get in there. There is supposed to be a drain hole at the bottom that can get clogged. Water could collect and rise, to the point of causing problems with the ECU. As others have said, I would encourage you to go and check these areas right after it rains. The body processor module is also in the trunk. If it gets wet, all bets are off.

The other thing would be the battery. Check the voltage at rest. If it is not "maintenance free" AGM, then pop the top and add distilled water to any low cell. Double check the wires off the battery posts, they have been known to fray internally and cause problems, possibly heat up, too.

If you have a second key, try with the other key, or even the valet key.

The right (but not necessarily free) answer is to check the codes. If the car does not start, there might be some temporary code, or freeze-frame data that can give you a hint.

Best of luck, keep us posted.

 

I have not tried the other keys but will have to wait for rain to do so. None in immediate forecast. Might have to start doing something outside to provoke a rainstorm. No water in trunk. All high and dry. No codes either.
This is acting like my old 60s British cars with points and condenser.....and condensation.