viscousTA

Sorry guys. I have posted this a number of times. I'm hoping to catch someones attention that had this problem. When the is rain in the air or washing my car. My car will not want to go, hesitates really bad. Then I gun it and it takes off. I have replaced the optispark, cap, rotor, plugs, wires (all MSD), ignition modual, and mass air flow sensor. I'm thinking knock sensor next. Any ideas? Anybody?

aboatguy

Get a spray bottle of water and mist the areas you believe the problem is in.

I'd look at high voltage side before looking at knock sensor

(opti, plug/coil wires , coil etc first)

Wiktorek25

o2 sensors

93M6Formula

I'm almost positive that its your Optispark,even a new Opti when any sort of moisture gets in or near those damn things your car will spudder and run like crap,

So be careful when your washing your car and avoid big puddles! haha those Opti's are tempermental.

LS1iFiEd

iTrader: (4)

Id say Opti,Your knock sensor is a sealed unit,The only thing that can get wet on the knock sensor and cause an issue is the connector.Is this happening when you wash just your car?Or more so when you clean the engine compartment?

viscousTA

Ok this is the weird thing. I've done spray bottle thing. If I spray the engine itself I have no issues even with a garden hose. It's when my hood is closed and it gets wet and not a underbody wash, just on top of the car it happends. But it does it in the fog too. I'm so confused. It drives me nuts. And it's getting worse.

LS1iFiEd

iTrader: (4)

So it gets wet, misses and hesitates then when you step on it,it clears itself out?Does it come back?Or only when you get it wet again?Hmmm,Does it have a Ram Air hood?It COULD be the MAF getting wet

trx250r

Yeah, I would say check MAF too. I wouldn't think fog would have enough moisture accumulation to arc when you are driving through.

cgEvan

iTrader: (1)

Mine does the same thing... except it's more random. It can be running rough at low/no throttle, but I can drive onto the track, run WOT, and lay down GREAT numbers. I've been told MAF or o2 sensors, since it clears up @ WOT.

rtucker

I had the same issue as you. It ended up being my O2 sensor extensions. They weren't making a clean seal and when I'd go out in the rain the car would hesitate and backfire constantly. I put electrical tape around the sensors and it's fixed the problem completely.

86formula

iTrader: (3)

O2 sensors, just buy real extensions if you dont have them or rtv/tape up the connections

viscousTA

No ram air. If I drive the **** out of it, it'll run fine, But it could be a good 20mins till it runs normal again. Now my voltage gauge is running real low. Could be a seperate problem. Probably is with my luck.

viscousTA

I replaced the mass air flow sensor a week ago and still have the same problems. I think thats what a MAF is correct me if I'm wrong.

Chevyguy358

iTrader: (4)

check the wiring from the opti to the PCM, mine did that exact same thing turned out the connector on the wiring harness was sitting on the intake(under the passenger fuel rail) and water was collecting and pooling there with the hood closed. As soon as it was restrained on the hook, it ran fine.