I have a really weird coolant leak, there is no leak when the car is off and sitting. When I get the car running, you can see drips of what looks like coolant dripping from the transmission/engine. The engine itself does not feel weak, idling at 1.1k, and I can freely rev it. It weird because when I reinstalled the intake manifolds, I made sure that every hose went somewhere and that everything is blocked off. Could it be that maybe the coolant is leaking through a hose or something? Or am I missing something? I'm getting kind of scared since when I searched I started reading about the coolant seal failure and I am HOPING TO DEATH that it isn't that. Or is it?

 

If you had coolant seal failure you wouldn see dripping water. Chances are you have a leak at the water hoses under the Throttle body.

 

Dripping from where? At the rear of the engine by the bell housing? If so, as J-Rat says, you may have a leak in the coolant hose that runs under the UIM. When the engine is running, the coolant system is pressurized so that is when a loose or failed hose would leak. After the engine cools down the coolant system loses pressure so no leak. If an internal coolant seal was faulty, you would likely see plumes of white smoke from the tail pipes.

 

might be bad seals in the motor

 

So after messing around with the car for a couple days I discovered it isn't coolant that is leaking, it was fuel. It seemed that it was either the injectors which were leaking/flooded or a hose was loose. I ruled out that a hose could be loose because I made sure those hoses were on secured. At one point, the leak was at a fair minimum of a couple drops, but I ran out of gas a couple minutes later. I then bought more fuel and dumped it in, and when I went to start it up again... it idled but the leak under the engine started getting worse. As time progressed fuel started leaking through the exhaust system and the engine would then stall out. This does explain why the leak only occurs when the car is on. But I then realized that I would have to rule out that my injectors are the cause of the problem, because I just had them cleaned and flow tested by RCEngineering earlier. And so I checked my fuel pressure regulator and figured out that it was leaking a bit, the vacuum nipple actually broke off the unit, and the gauge no longer reads anything. I am assuming that this is my problem for the obvious reasons, but would the replacement that I ordered help fix this? Or could my symptoms be leading towards something else? I'm guessing that because my fuel pressure regulator is bad, there isn't anything to regulate the flow of fuel of my aftermarket bosch inline pump, thus resulting in flooding EVERYTHING! Right?

Edit-
But when I did have the car idling, it is obvious that the car is running rich. You can smell it to believe it, and white smoke was present in the tail pipe. Could it be because of the flooding or is that separate meaning that I still have a coolant leak? Its hard to tell when you have a bad nose too.

 

Sounds like your PD has kicked the bucket, time for a banjo bolt....(hope you have an S4) . I wouldn't drive around until I got that sorted out, engine fires are no fun.

 

Its an S5 so the PD is actually welded to the secondaries, and yeah... I'm going to leave it alone until I know for sure what the hell is going on.

So I would have to replace the fuel rail right? But could that be the problem? I bought another aftermarket FPR but that is going to take a while to be shipped. Eh.

 

So all in all, after I replace my Fuel Pressure Regulator (which is confirmed bad) will prevent any fuel leak/spill from the injectors right?

 

Well if it was the injectors that were leaking to begin with then no, a new fpr won't help anything. And if your PD is bad it won't stop that leak either. But if the FPR was the cause of the leak then replacing it should solve your problem.

Is the FPR attached to the rail like the PD on the S5?

Ever consider converting to an S4 rail?

 

-Before, nothing actually was leaking. I had no problems before, it was that the FPR wouldn't hold anything above 25PSI during idle... which was still too rich. Now the FPR reads 0PSI, leaks, and now I am having the flooding problem. I just want to make sure it could still just be the FPR because now you got me kind of worried about the PD thing... I definitely DON'T want an engine fire.

-I have an aftermarket FPR which requires you to attach the "In" Fuel Line and a vacuum hose from the manifold, then the FPR's "Out" Fuel Line then goes to the engine "In" Fuel Line.

-I made a mistake before stating that the PD is welded to the secondaries when the PD is actually welded to the primary fuel rail and the regulator is on the secondary rail.

-Not really sure what the benefits would be to switch to the S4 rails. I'd actually like to try and keep everything on the engine to stay as a S5, just to prevent headaches later in remembering what parts are actually S4 and S5.

 

anyone got a diagram of the coolant hoses under the intake manifold of a s4 t2? mine is leaking from somewhere and puddling up by the intake manifold and either i cant find it or i am blind

 

you said you took off the Manifold?...then check the O rings At the injectors.I am Guessing that your Fuel leak is there.

 

^^ +1

I tore off the manifolds and got to the primary fuel rail, but before taking it off I noticed a puddle of fuel mixed with some coolant sitting on top of the block. Damn. I cleaned it up and removed the primary injectors first. I saw that the injector closest to the rear of the engine had a deformed/ripped o-ring which didn't seal ****. The other one had a good o-ring but I replaced them both just in case, but not without coating them with some oil first. When I got to the secondaries, I took them out just to have a look. Both had good o-rings but 1 of them had a very small rip and so I just said forget it and replaced them both. So now I'm letting the silicone cure around the manifolds before I try and crank it to check for leaks.

Thanks for those who read through the thread and helped me out.