Regulator

iTrader: (7)

I drove my '02 Z28 into work this morning in the rain, it seemed to be just fine until the truck next to me threw a lot of water over into my lane, and that's when I noticed it started to stumble/miss in 3rd at low rpm. When I started driving home from work, the car just didn't sound the same, and the missing started getting worse, at low rpms again. I drove to the gym and on the way home, it sounded like I'd dropped an entire bank, and now it's noticeably missing at idle all the way through the rpms. Could it all be related to the water this morning, or am I possibly looking at a bigger problem?

LS6427

iTrader: (2)

Yes, water will do that. Did he splash you on the passengers side by chance? Your PCM could have gotten wet, its on that side.
Also, wet 02 sensor wires will make you run like ***......
Also, just getting water all up into the engine bay onto all the wiring harnesses.

It takes some time to dry out. DO NOT drive it aggressively while its missing or stumbling, you can cause severe damage by doing that. Nothing wrong with driving it completely chilled out like a grocery getter till it dry's out.

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Regulator

iTrader: (7)

Yeah actually it was on the passenger side. I just drive it pretty normal during the week, but I will definitely let it dry out for a couple days. Anything I can do to speed up the process?

Element

iTrader: (5)

Park the car in the sun and leave the hood up. One thing not to do is to use compressed air to try and blow water out of the engine bay - you'd just wind up forcing water past seals into places it shouldn't be.

LS6427

iTrader: (2)

Time....or a long drive on the highway. But really, its just gonna take time. Like element said, open the hood and let it sit outside. A fan blowing across the engine bay can't hurt.

Alot of times the water gets into the spark plug wire boots, so taking them off and drying them could take care of it. But you could also break some wires by removing them....so its your choice. A new set is just $36.00 at Advance Auto. Your choice. It might be the wiring harness near the PCM that got splashed and the PCM itself. I'd pop the two tops off the PCM to see if there's water in there where all the pins are....you could fry your PCM if there's water in there. Thats easy to dry out if you see water in there, hair dryer. Blow the hot air into the two plugs to dry them out too.

Other than that, the water could have gotten into a million places that will cause it to run rough.

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Regulator

iTrader: (7)

Let it sit at home all day today, in the sun, in 90+ degree weather. Got home, fired it up, sounded good, took it up on the interstate for a few minutes. Got up to temp, felt strong again, pulled hard, no hiccups. Stopped by my insurance, came back out to start the car, now it's missing again. Drove it down the street to the house, not as bad as yesterday when I drove home from the gym, but worse than when it first started yesterday morning. I'm going to try and pull the plug wires and maybe try some new 02's (they are lengthened for the L/T's).

I have this fear in the back of my mind that I've somehow managed to blow a headgasket, but the car has never overheated or given me trouble before this. I just recently changed the oil, the oil in it was pretty clean, not milky or anything. Car doesn't puff smoke at all. I guess what caused this worry is that the coolant resovoir tank dipstick had this dark brown gunk on the very bottom of the stick that I noticed when I did the oil change. It's not milky, and it doesn't appear to be mixing with the coolant. After the oil change it doesn't look any different, and the oil dipstick is showing very clean. Am I just being paranoid or is there legitimate cause for concern?

Bobsmyuncle

iTrader: (32)

get some dielectric grease in your o2 plugs. see these threads daily on here. and after mine did it, its an easy diagnosis. lol

Regulator

iTrader: (7)

The sensor connectors? I'll give that a shot

Regulator

iTrader: (7)

Hopefully a final update. Decided to bring it up to temp to put my paranoia of a headgasket to rest, topped off the radiator and kept the cap off, saw a few bubbles at first when it got up to temp but I think that was because the coolant was low when I first started it but after squeezing on the upper/lower hoses a couple times it didn't show any more bubbles. Capped the radiator and drove it around for about a half an hour, it didn't hesitate or stumble like before so I think it's finally dried out! Still plan to put a little dielectric grease on those o2 connectors tomorrow when I do the suspension. Thanks everyone for the insight and saving me from a lot of worry.

eseibel67

iTrader: (10)

You have your O2 sensor wires lengthened. Wherever they're connected, it's very sensitive to moisture. I would recommend the longer Corvette O2 sensors to avoid the extensions.

Regulator

iTrader: (7)

I think I might have to invest in those. I'm getting agitated at this point. The car seems to run without any hiccups or issues, no codes, but now the exhaust note is noticeably different. It doesn't sound nearly as "crisp" as it did before. It's an LM1 with a Magnaflow resonator welded in, and I loved how it sounded, but now it's like it's missing something. I want to say almost like it's "missing" some exhaust but the car doesn't run rough like it's on 7 cylinders or anything. It also sounds like there is more header tick on the passenger side than before. Could it be associated with the o2's still, or perhaps something more?

LS6427

iTrader: (2)

That junk on the overflow tank dipstick is probably just old Dexcool that got in there long ago.

If you have extensions on the 02 sensors...thats probably where the water is. I wouldn't spend money on new sensors until you try to take the extensions off and dry them out.

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