KingHamer

I was driving home the other night and my car oil level sensor came on and the coolant sensor came on, I was close to home so I was hoping I could limp home, but the car started stalling, shut off, and started smoking.

Codes showed random cylinder misfire, so I replaced all the coil packs and spark plugs (it was time to do so anyways) that much I got handled, but still misfires.. I did drop one of the spark plugs while I was installing, ill assume thats the issue, Ill go through and figure it out. I also decided to replace the valve cover gasket again as the last time I don't think I did it so well and the car was loosing a good amount of oil.

I did notice that when my car shut off the night, it showed the low oil error and the word "sensor". Does this mean my sensor is no good anymore??

As for the major coolant leak.. I pour in distilled water and it literally all dumps out, right in the center of the engine where the radiator meets the engine, I can't tell exactly where its at, but its between the oil pan and the radiator, pretty close to the oil level sensor, maybe 2 inches the right of it.

After doing a little research, I am going to assume that my auxiliary coolant pump, my thermostat or one of my hoses is no good, correct?? Is the water pump and the auxiliary coolant pump the same thing?

Right now I have the car in service mode, bumper off, headlights off etc, so I'm ready to tackle it, just need to know what I need to replace or what I'm looking for, I haven't really gotten into this area before.

Thanks for everything guys, I do appreciate it, I will post a few photos and maybe a video here in a bit. I am going to tackle this myself If I can, shouldn't be too hard, most of the hard work is done since I'm in service position :P

KingHamer

After looking closer, its also coming out just left of the oil sensor as well, theres two hoses that meet there, I'm going to assume A/C hoses, they are metal.

Also leaks a little bit on the ground near the rear of the engine, probably from the reservoir itself.

I am uploading a video to YouTube right now.

KingHamer

Here's a good video.

rocketman4321

No, there's a water pump driven by the timing belt on the front of the engine, and an aux coolant pump (at least on the 2.7T) that under the intake manifold on the top of the engine.

Since you're already in service position, can you locate a leak on the front of the engine? There's the water pump, thermostat housing, and a couple hoses coming off the housing.

However, this doesn't explain why you got oil and coolant lights at the same time, and why either one would cause a misfire. Is there coolant in the remaining oil? If so, this may be a blown head gasket, causing loss of compression and a coolant leak. Also, is the timing OK?

Yes, there is a warning light for the oil level sensor--yellow, and distinct from the low oil warning. But given the other problems here, I'd put that one on the back burner. It doesn't affect the operation of the car unless you lose oil and don't notice. Easy fix--drain oil, 3 bolts and one connector.

rocketman4321

One other thing--on a reread, was your oil actually low, or was it just the sensor light? If you still have oil, maybe all the coolant flowing down got in the sensor connector. Another reason to find the coolant and rough-running problems first.

jseklund

Well....this could be a number of things.

On the oil light - was it flashing red or yellow? Flashing red isn't level, it is pressure and that is a different sensor.

As was asked - was your oil low?

The auxiliary water pump is located under the air intake manifold. If you take off the pipes going to the throttle body and look in their with a flashlight...to the right or the left of the throttle body, you will be able to see the lines and if you look around the valley pan you will see if their are signs of coolant leaks. With a leak that big, you could always pour and watch.

The water pump is located in the front of the engine, almost dead center, and the thermostat is located right next to it. Both the pumps and the t-stat housings can be sources of leakage.

I doubt dropping a spark plug is your issue. If you have a code scanner, it will tell you which cylinder is misfiring and you can just swap it with another cylinder and see if it changes....

The questions I have:

1. When was the last time the timing belt was changed?
2. How many miles on the car now.
3. Yellow or flashing red oil light.
4. Does the car start OK, beyond misfires?

KingHamer

1) I couldn't tell you the last time the timing belt was changed.. I've had it 2 years, 30,000 miles and haven't changed it, its looking a little rough though. I'm think it was changed a few months before I bought it, but I could be wrong.

2)149,xxx

3)Yellow flashing oil light, but right now its okay. I let the car run yesterday for 45 minutes, just idling. Oil level was good, it did leak a few drops, but I'm not too worried about that. Little bit of smoke, I think its coming from the gasket maker I used when I replaced valve body gaskets. The smoke smells more like coolant though.

4)Starts up great, it takes about 2-3 seconds to start up though, which Is normal for a misfire correct? Also, I went and unplugged every coil pack plug, 5 of them made the engine stutter for about a second, then got back on track. 1 made no difference when I unplugged it. I'm not sure which number it is, but its the one on the passenger side, front of the engine.

Thanks for your help guys

KingHamer

I am going to take the radiator off sometime this week, I will try to find out then, thank you!

CRuby

Here's pic of cooling circuit for ABP 2.7 engine.
Aux coolant pump is #13 located in valley underneath intake manifold. The way water is pouring out the right side, makes me think it's not the aux pump or it's hoses. I think you'll need to get a better look up into right side to find the leak source. But...be safe. It appears yo have car supported with right brake rotor resting on a wood 2x4 & left side held up with a floor jack.

jseklund

Great, so....these cars require timing belt changes every 75-90,000 miles. Audi originally said 90,000 and there were some failures so they reduced it to 75,000. Generally speaking, if you have one of these cars, you NEED to know when it was done or your are playing with fire. The rollers can seize, which breaks the timing belt, which totals the engine in most situations. Since you are taking the front end off, it may be time to do this....and if your water pump or t-stat is leaking, it's a good bet you should.

If the original owner did it at 75,000 - you are at another 75,000 right now. If they waited until 90,000....you are 60,000 over. If they told you they did it a few months before you bought it....and it was over 100,000 miles....then who knows?

As for the yellow oil light - there are two - one says sensor and one says oil I believe. The red light is for the pressure sensor. If your oil level is full and you are getting a yellow oil light, chances are the sensor went bad, or the pickup screen inside the oil pan is clogged. I'd bet on the sensor if you've used synthetic oil and regularly changed it.

The cylinders are numbered 1-3 on the passenger side and 4-6 on the driver's side. 1 and 4 are at the front of the engine (bumper).

If you plug in a code reader it will give you a misfire code - P0301, P0302, P0304, etc.

The P03XX means misfire and the XX part is the cylinder that misfired with 00 being a random misfire.

Once you've identified which cylinder is misfiring pull the spark plug from that cylinder and swap it with a cylinder that is NOT misfiring. i.e. - if you get a P0303 code, pull the plug from cylinder 3 (the back passenger side) and put it in cylinder 6 (back driver's side) and put the plug from cylinder 6 into cylinder 3. If you suddenly have a P0306 code, you know the spark plug was bad. If nothing changes, then do the same thing with the coil pack. If you have a P0306 code then, you have a bad coil pack. If nothing changes still, you don't have a spark plug or coil problem.

Before you worry about the misfire though...I would try to find the coolant leak and make sure the timing belt solid, and decide if it is time to replace it.