Please Help: Engine Misfiring.

[coool11]

Hi All,

 

I have 2001 Silverado, V8 4.8 and manual transmission.

 

(With headers and K&N filters).

 

 

My problem is when driving in raining weather or washes my car.

The engine starts misfiring and run roughly,

"service engine soon" light starts flashing and the car hardly accelerate.

It only happen when water reach under the truck and when i leave the car to next days

it runs very good like nothing happend!!!

 

Guys, from yours experience what do you think the problem is?could be O2 sensors?or else

[Draenor]

What codes? I'm sure their cylinder missfire. I dont think it is O2 sensors, definitely ignition. When you wash you truck, are you spraying under the hood or just in from the wheel wells?

*If just the wells, keep the truck running next time and spray each side, that will indicate on which side the problem is on.

[coool11]

... Draenor ....

 

thank you for your respond

 

the tech. in the shop is sure it's the O2 sensors. i just bought them (4 sensors)

they cost me a good amount of money and he will install them in the morning.

I hope he's right. i'll keep you posted.

 

thank you again.

[redvett]

Don't waste your money on the post cat O2's wont affect the driveability check the wiring harness.