2004 Envoy batteries drain, headlights flicker

[sundevil99]

Hello,

I have a 2004 Envoy SLE 4WD with Vortec 4200 inline 6 cyl engine (automatic transmission). It has 33,000 miles and has been driven for just over 2 years.

The entire time I've had it, each time it rains (not often here in Arizona) or when I leave the car wash, as I'm driving down the road at a steady speed, the headlights will flicker 2-3 times and the engine feels as if it is going to stall. This happens when I am driving steadily, and not when slowing or accellerating, nor when I am idle at a stop light. The one consistent piece of the puzzle is that it definitely happens when the vehicle is wet, and never any other time.

One year ago, I took it to the dealer it was purchased from and told them. They said there was nothing wrong with it. They upgraded the firmware and sent me on my way. I took it to an auto chain to have the battery tested. When they hooked up the tester, it FRIED the tester completely when they tried to check the battery. Luckily, they didn't charge me for damages. I took it to a different dealer who also said there was nothing wrong with it, but they changed the battery at my request.

Last week, I got in the vehicle to go to work, and it really hesitated to start. I took it into a third dealer, who said the battery was dying. I told them about the flickering and the hesitation of the power while driving. They changed the battery and said there was nothing wrong with it.

Today, I took it to an independent mechanic. He took a hose to it while running the engine and recreated the problem. He said it shows these symptoms when water gets into the air box through the air intake valve, connected to the air filter. He showed me in this part where water consantly sits in the bottom of it after the vehicle is wet. His only recommendation was to get online and see if others are having the same problem.

Remember, this only occurs when the vehicle is wet. I'm not sure if it is connected to the fact that I keep having to change the battery out or not. It may be two different problems.

Any suggestions? Thanks in advance. Sorry for the lengthy post!