Ok I am on the verge of selling my lexus b/c I can no longer deal with this problem. The problem came out of no where and has been there ever since. For some reason it seems to ''activate'' the problem when it rains, although there is no water on the ecu or any electrical components that I can see.

I did a tune up on it(plugs, wires, cap, rotor, fuel filter and fuel injection cleaning), the car ran fine for a month. I didnt drive it for two days and out of no where it just started running like crap. Barely idling, no power, sluggish acceleration. I pulled the plugs out and inspected them any they were all white(lean). So I started inspecting and replacing things just because I had the parts at my disposal.

Replaced:
Maf
CTS
Cap
Rotor
Wires
Plugs
Reset ecu
Replaced ecu
reset TPS
o2 sensors

If I clean the plugs the car will drive for a day and then crap out again. If I cant figure this out by this week im selling the car for a grand. Ill go buy some Honda with less electronics and less parts to break. Does anyone have any idea wtf could be going on with this?

 

Any CEL on the dash?

 

check the gap on your plugs sounds simple but these cars are sensitive to the plugs being the wrong gap i have been there with it...under your hood you will see the sticker that tells you what your gap is suppose to be

 

Check for vaccum leaks

 

Don't know if this would apply to your car, but I just had to replace my Accelerator Pedal Position sensor which crapped out on me. Idled fine but applying throtttle would not raise my rpms most of the time. No misfiring though.

 

Fuel pump, Fuel pump ECU, Fuel filter ?

 

possible engine ground issue

 

id guess that it would be a grounding issue as well. 2nd thing id check is make sure the plugs are RESISTOR plugs. iv seen a couple people put non resister plugs in a 2jz and it does not work. 3rd is id check the ignitor. last thing id check is to make sure the wires which go into the distributer are good, that those connetions are good. the ecu functions off a cam signal from the distributer. if the timing is off this is possible as well.

 

Sounds like a bad ign. coil

 

Two cheapest possibilities (before you go to a Civic) - replace the ignition coil (under $20 at JC Whitney), and test the fuel pressure at the rail while running (there is a valve on the fuel rail for just that test). If the fuel pump is not supplying enough fuel then do the 12 mod (found on this forum) which eliminates the lower voltage setting of the fuel pump but may cause you to run rich at idle and low RPMs. If that doesn't get you enough fuel, replace the pump.

Good luck,
Wade

 

Lol, I just went through the same problem a few months ago, it would rain and my car ran like ****, fell on its face. Come to find out there's a piece of weather stripping that seals the hood to the bay toears

 

Lol, I just went through the same problem a few months ago, it would rain and my car ran like ****, fell on its face. Come to find out there's a piece of weather stripping that seals the hood to the bay towards the back of the motor that ends up coming loose and just hanging, then when it rains the water goes straight between both valve covers and gets the coils or wires wet, thus giving you a random misfire or hesitation, I fixed mine and never had a problem in the rain again*

 

Finally after two months of not knowing what it was I finally fixed it!!! It was the distributor!!!!!!!

It threw me off a little b/c I had already replaced the cap and rotor, so I figured I could cancel that out. I sat down and jotted down some ideas and came up with possibilities that would make it random misfire and run lean and to me there were only two things. Fuel issue or ignition.

It works now I appreciate every ones help

 

glad its running. so you had to replace the entire distributor? maybe one of the sensors inside went bad.