Hey guys I’m new to the forums here. I have a 2007 g35x sedan with isr long tube headers, custom catback exhaust, drop in filters and tuned on uprev. No codes are present either.

For the past few weeks, we’ve been getting rain and every single time it does rain, my car would go into limp mode, or fail-safe mode where I can’t rev past 1.5k rpms. This usually happens after starting the car and sometimes the car wouldn’t start, it would crank but doesn’t turn over. This usually happens twice and then when it does turn over, that’s when the car goes straight into limp mode. I have to wait about 10-30 mins and I can rev freely afterwards, but I’m scared to drive it in the rain in case the car stalls when I’m driving.

So far I’ve checked my passenger floorboard to see if it was wet and it wasn’t at all. All electronics works as they should. Is there anything else I should check? This only happens when the car sits overnight in the rain. Any experiences and feedback is appreciated. Please help me figure out this annoying issue Thanks!

 

It's good that your passenger floor is dry, that would indicate your BCM is fine. But check around your IPDM under the hood behind the battery. Be sure the windshield cowling and associated rubber seals and covers are all intact and doing their jobs. You don't want water running down the battery side of the firewall in that area. If I'm not mistaken most of the engine functions, including start, are done by the IPDM so check that unit to be sure it's dry.