Alright so the whole story is ... My friend drove my 97 Blazer, 4x4, automatic, 4.3L Vortec.. into about 2 feet of water, hit a rut got stuck for about an hour and water got into my intake,. Two days later with the spark plugs out turned key over and got A LOT of water out of there, put the plugs back in truck started up fine... Turned it off looked at oil it was milky... Water got in there too somehow. Did two oil changes and its a lot better but still milky, so is there anyway to kinda clean it out instead of doing many different changes? And also, yesterday I started my truck up and it just went high revs, but since no techometer I have no clue how high it was getting, I put it in reverse and kinda dips down but then goes, and in drive i can take my foot off the accelerator and it will keep picking up speed.. Not sure what is going on... If you could help that would be awesome.

 

Does the oil smell like coolant? How is your coolant level? As far as the high idle, try cleaning your MAF sensor. Also, take a look at the distributor cap and look for corrosion or signs of arching. You may also have a vaccum leak, so take a look at the vaccum lines.

 

Maybe pull your throttle position sensor off the throttle body and let it dry for a few days. Probably water inside it shorting it and telling the computer you are hitting the gas pedal when you're not.

 

The oil doesn't smell like coolant, the coolant level is alright last time I checked. Tried cleaning lots of different things, replaced the TPS because computer said throttle was opened 33% while motor was on acc. Now it only does the high idle is Park and Neutral, but when put into gear (drive or reverse) it calms down in a sense.

I am not good at vacuum lines, so if there is a leak i'd probably NEVER find it. Lol.


Now I know it could be anything like vacuum line, idle air control valve (not moving), mass air flow sensor, map sensor, etc... Thinking of taking it into this local shop that charges between 15 and 45 dollars for a complete look over.


If anything else pops up before then, please feel free to message back. Thanks.

 

Don't forget about EGR. That will appear as a vacuum leak as well.
I am having a similar issue except I didn't drive through water. I have also suspected Crank Position Sensor as well but it seems more of a vaccum leak in my case because the RPM drops as well when put into gear.

Used a vacuum gauge on the engine this morning and found that pushing on the TPS affected the idle speed(running lean). I do not like the way the TPS mounts since it makes adjustment very difficult. Anyway, I found that the sensor must be turned closckwise when tightened. If turned counter clockwise the internal potentiometer goes open. In my case at least.