I own a 2003 SC 430 w/ 133K miles. It has been serviced regularly since purchased. While driving in RAIN ONLY the engine may suddenly growl and shake. No check engine light or other warning lights illuminate. When I pull over and restart the engine, it runs fine again. There are never any such problems when driving in dry weather conditions. Has anyone experienced this problem or knows what the issue might be?

 

Water going into intake??? Not sure never heard of this hapening into any car....only bogging while my boys 350Z drives in the rain with a cold air intake right installed low close to the street

 

Sounds ignition/electrical. Are all the engine shrouds in place?

 

Water shorting out a coilpack or two. Get the car to an independent Lexus service center and give her a once over. As a MINIMUM, change ALL spark plugs for the correct Iridium plugs, and tell service technician to correct any oil in the plughole problems or water shorting out coil pack issues.

 

Thanks to all for your comments. By way of elimination, it appears to be harness/plug related. After servicing I'll post the outcome. Again, appreciate everyone's feedback. Stay well - Blackfin