97 blazer misfiring exaust took in water

Hi everyone. I have a problem with misfiring. I backed my boat too far in the water and got stuck. it took time to get it started after i got pulled out and ran with a misfire. That problem cleared up. Then the next day i start my car and it misfires bad again then cleared up again. Now the next day it misfires again and will not go away. I was on an incline backing my boat down and i dont think water could of gotten up to far. Any help with this would so be appriciated. Loose my job if I cant fix it. throws random misfiring code.

Pull dist cap and check for moisture in it or cracks.
Other things to look at is moisture on or in plug wire and engine wiring.
Pull hood after dark and see if any spark jumping around.

I will do. But the motor was actually never in the water just the back half of the truck. Water had traveled up the exaust. I will check the distributar anyway.

Well I tried this today and still no change also i changed the plugs. codes throwing is It sensor high imput., Mass oxygen sensor low imput but i unpluged it for a few minutes. Lets see 2 cylnders misfiring and a emissions code.

Did you check cap and rotor and wires?
What code no did it have?
What sensor did you unplug?

Well after doing all this I came down to one cylnder number 5. I have plenty of spark to the plug... The thing is when I unhook the sparkplug wire to the plug the truck runs exactly the same. I'm thinking a cylnder is blown out or stuck valve. Does anyone know how to unstick a valve?

Well after doing all this I came down to one cylnder number 5. I have plenty of spark to the plug... The thing is when I unhook the sparkplug wire to the plug the truck runs exactly the same. I'm thinking a cylnder is blown out or stuck valve. Does anyone know how to unstick a valve?

Proper testing and checking out first before throwing valves and cylinders at it.

Is miss still coming and going?
Have you checked cap and rotor?
Have you checked the no 5 spark plug?
How many miles since last tune up?
Any codes or check engine lights?


They make compression gauges for ckecking valves or lose of compression.
Good Luck

The garage fixed the number 5 injector Now I'm getting a number 3 cylnder missfire. Damn it. Back to the garage it goes.

If you have injector issues, changing a single injector on the spider usually is a hit and miss fix. The reason being, your disturbing the other injectors which are worn out/dirty as the original injector problem. The best fix to this is to change the whole assembly(spider) unit.