Stumbles When Its Wet

[Ray92es]

My 92 ES starts up fine but when it has been raining, it stumbles upon acceleration for a minute or 2 and then runs fine. If car is warm, will start and run fine.

I thought water but it will happen even if ther has not been enough rain to get anything wet. A heavy fog can do it also.

Since this is an infrequent thing, I hope someone has run into this and resolved it

[tckcumming]

My 92 ES starts up fine but when it has been raining, it stumbles upon acceleration for a minute or 2 and then runs fine. If car is warm, will start and run fine.

I thought water but it will happen even if ther has not been enough rain to get anything wet. A heavy fog can do it also.

Since this is an infrequent thing, I hope someone has run into this and resolved it

I had this exact problem on my '93 ES.

I had replaced my plug wires about 6 months before, so I figured it wasn't that. I opened the hood once when it was sputtering at idle and was amazed at what I saw. Blue sparks about 2 inches long arcing from the distributor cap to the metal base. I installed a new distributor cap the next day, it seemed better but I could still hear a faint clicking sound coming from somewhere near the distributor. So I pulled out my old plug wires and replaced the new ones that I had noticed arcing the night before. Engine ran a bit smoother, but the clicking sound had changed - it became more irregular, like it was skipping every once in a while. So I went ahead and just put all the old wires back on in place of the new ones. Clicking sound gone, engine ran smooth as silk. I sprayed a mist of water on the cap to check it, no problem.

So I finally figured out that my "new" replacement plug wires were faulty. They were "Xact" brand, aftermarket parts. They looked and felt exactly the same as the OEM Toyota ones when they were new. But when I pulled them off, the rubber boots on the plugs had become soft and mushy, and one of the boots on the distributor came off in my hand. They were useless after 6 months.

I'd start by replacing the distributor cap and rotor, and the plug wires - but only use OEM Toyota parts! The aftermarket ones I bought weren't that cheap, and they turned out to be crap. Replace your PCV valve with an OEM one, too, if it's old. OEM plug wires are pricey, you can probably find a deal online at one of the Lexus parts suppliers. Cap, rotor, and PCV can be picked up at any Toyota dealer and are not a lot of money.

Good luck!

tck...