Flushing Water Through Egr??


New Member
Sep 13, 2013
So I realized in my stupor that while trying to flush the coolant system in a 93 5.0 I put the flush kit on what I think is the egr valve and ran water through it and water started coming out of the exhaust. I haven't tried to start the car but I realize I did this wrong and I feel like the biggest idiot ever. Did I just screw everything up?? I attached it to this hose by mistake thinking it was the heater hose.


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Those aren't heater hoses. Those are air. Lines that run from the smog pump to the cylinder heads and the exhaust. You definitely do not want water In these. The heater hose is on top of the lower intake. And is metal. Trace the water pump back to the firewall
Oh I know they're not supposed to have water in them, but too late, I already ran water through them and now I'm freaking out after I realized what I did. I'm afraid to start the car or do anything until I figure out if I can fix what I just did. I checked the oil level and there's no water in the block but I'm not sure about the head
I'd be concerned about hydro locking the motor by pumping water into the cylinders. How long did it run? Was the engine warm? It's possible if the engine was hot it dumped all the water into the exhaust only. If that's the case, at this point a healthy drive to burn off the water might be your only option short of unhooking the h-pipe and draining it.

Can always yank the plugs too and turn the engine over to rid it of water
Only about 30 seconds when I realized it wasn't coming out of the radiator but instead the exhaust pipe. Engine was cold. Any suggestions? I'm going to go pull a spark plug now and see if water comes out
Ok took and leap of faith and started it up obviously with no water and it started and everything seemed like it was running fine so hopefully it might have been a mistake, but not one that will cost me a motor or need a rebuild I hope.
Is this for real? I remember years back the story about some guy flushing his motor out with water that later turned out to be fake story.

That's not your EGR it's your thermactor hoses for the smog pump and system. On end of the tube goes to your cats and exhaust, one to the smog pump, and then the top hose to the back of your heads. Hopefuly you disconnected the hose to the back of the beads.

IF you did this.. you need to change your oil and filter now after you remove all the plugs and crank over the engine to blow out all the water. Spray some oil into each spark plug hole and crank it over, and I mean crank it for a good minute. Undo those hoses to the motor and let the smog pump blow out all that water.
It really happened no joke. I'm that guy. So if I pull all the plugs and just crank it should pump the water out? I checked the oil level and it was fine like no liquid went to the motor. Also the spark plugs are no wet or anything. I'm going to pull all plugs and turn it over for a while. And then change my oil again. I don't have enough oil to change tonight. I tapped into the top hose on the other side of that little vacuum canister and ran water with the motor off not running. I realized itwas coming out of the exhaust. And turned it off. I then freaked out obviously and then checked my oil level thinking the motor was going to flooded with water and then pulled one plug thinking it may have water and neither did. Oil level was exactly the same as before as well as the same viscosity. Do you think it just dumped right into the exhaust bevause the motor was off and there was no vacuum? Is there a small chance that everything could be ok? I was going to change my radiator, x pipe and headers tomorrow anyway.
I'm really nervous and freaking out and I want to leave it til tomorrow morning and then do all that. Only because I'll need oil to change it again. Can this wait until tomorrow and then pull the spark plugs and pump it out if there is water in there. Like I said the oil level on the dipstick was completely normal. I can't believe I did something that stupid. I've had the car 2 weeks and I was trying to upgrade the radiator.
this is from @jrichker , maybe this can help you look at it. Maybe you did it before the diverter valve or just before the check valve going to the cats?? The orange lines?? If it was the orange line you should be fine just heat the car up and drive it around to blow out and evaporate any left over.

Thermactor Air System 65%.GIF
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If you started it and it ran, you are all set. If water was in the cylinders it would have hydro locked.

What you need to do is remove those vacuum lines on the side of the engine and verify there is no water in there. Basically just undo the hose clamps at the smog pump, and at the rear of e engine where the rubber meats the metal pipe going to the heads and to the exhaust. Make sure that's all clear.

Change the oil just in case.

If the engine never ran, how did it come out of the exhaust? The tailpipes?
It was running down into the exhaust pipes and and out. The smog lines run down into the cats and out and since the engine was completely off when I turned the water on, it just ran into the diverted valves that were blocked off and then down int the cats and out of the exhaust pipes but never made it to the block. I pulled all the plugs and nothing was coming out of the but atomized fuel no water. I think I lucked out gentleman. I'm pulling the smog pump and ac anyway in the next few days anyway. The oil looks fine but I'm gonna change it anyway tomorrow. Can I leave the spark plugs out of the cylinder tonight and change the oil again tomorrow? I feel like the dumbest person on planet earth right now. I just literally didn't pay attention, spliced that line and went to it. I wasn't even drinking!