oil leak

I cannot think of any oil lines up there. But are you sure it is oil and not power steering fluid? They can kind of look the same and be confused easily. And if it was leaking from the reservoir it could easily ride along with the belt around to the alternator, water pump, and A/C compressor.

could it be from the head gasket?

Highly doubtful that it had manage to come out there and get up that high. The only oil seal up there is the front main seal, and it would not have the pressure to blow out like that. It would be seeping out and going down the front of the engine. But the power steering system has pressurized lines up there. A pinhole leak could shoot power steering oil a good distance and definitely get it up there.

so I should inspect the power steering?

Definitely. First start the car and raise the hood. Poke around with a flashlight and see what you can see. When you see where it is coming from, take a picture or two and we will try to identify exactly what it is.

okay, I will do that tomorrow.

check the level of power steering fluid and engine oil.

I checked the engine oil yesterday and it was full, but I have not check the power steering fluid yet.

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another photo.

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Get some engine degreaser and spray it all around there. They have got instructions on the can, just make sure not to spray any electrical connectors. Then see if it comes back. To me that looks like just years of gunk and grime building up. It could be a leak of some sort, but I am not sold on it being a leak. Do go ahead and check all of your fluids, so if one is leaking you will know for sure.

If it is engine oil, it is probably from old dried out valve cover gaskets. A common issue on these cars. That is a common issue on all cars. It would be a slow leak, that runs down the front and/or side(s) of the engine.

See what you find.

thank you for the reply I just recently bought this car a month ago and owner told me he just replaced the valve cover gaskets. engine oil and power steering fluid is full.

If the gaskets have already been replaced, then that is probably just old crud that was not cleaned up. Still a good idea to degrease it and see if there is a leak there. If there is a valve cover gasket leak, it would probably just mean that the bolts need re-tightening.

Okay cool. do you know what would set off a cel code for P0405-Exhaust Gas Re-circulation Sensor Circuit A Low? replaced EGR a few weeks ago code just popped up today .

P0405 is saying that the signal voltage coming back from the EGR pintle position sensor is too low (possibly 0).

The way it works, simplified, is that the power-train control module (computer) supplies a twelve volt lead voltage to the sensor. The voltage goes through the sensor, and depending on the position of the sensor, returns a signal voltage. When that signal voltage is consistently less than 0.14 volts, the code sets.

Most likely causes are going to be (1) a failed sensor, (2) no reference voltage from the PCM (basically the lead wire is broken/shorted/screwed up at the connector) or (3) The ground wire is weak.

Basically, you need to make sure that you have twelve volts coming from the PCM and that the ground wire is good. If those are good, then most likely your issue is the pintle position sensor (built in to the EGR), which would not be terribly surprising if it is an aftermarket EGR valve.

You can also check the signal voltage going back if you can get a lead from your multimeter into that wire.

yea, i am going to take it to a shop to check it.

Okay, it is really not hard to actually test. Just sounds difficult. If you have a $10.00 multi-meter, you can do all of that testing. Or you can pay someone $80.00 to do it.

well I also have P0410 code popping up. I already replaced the air pump and both check valves and checked the hoses but the code continued to pop up.

Regarding the P0410 - Check #35 in the images below. It is the relay for the air pump. You can buy a relay for a few bucks and try it. Cannot hurt.

if the relay is bad would the pump still come on?

Maybe. It could get stuck on or it could not be coming on at all.

it comes on for a minute then shuts off.

Well it is not that then. Something has got to either be plugged up or the valve on the pump is jammed.

is there a switch for the check valves?

There is a check valve in there. I *believe* it is in the hose leading from the pump to the exhaust. I am attaching a diagram that is provided by GM. Personally, I would bet that that check valve is not opening and that is what is causing your issue. It is likely a dealership only part, but it would not hurt to try the local auto parts shops and rock auto.

so when the air pump comes on is it suppose to sound like humming or a mini vacuum?

Something like that. I haven't specifically heard the one on those cars, but that's the general gist of it. Find that check valve. Replacing it shouldn't be expensive (Check valves aren't exactly new and exclusive technology).

I just replaced the valves couple weeks ago

Well from what I understand, the code indicates that there's some sort of flow error from the pump. So if you're hearing the pump run, and feeling it blowing air, then there has to be a blockage or something along those lines.

I suppose that it's possible that the oxygen sensors (readings used to set this code as well) could be reading incorrectly. But I doubt it. They'd have to not change as expected when the pump was running, which seems unlikely to me, especially without any other oxygen sensor codes.

well today I change the relay and when I was changing the relay I only got a portion of it out and then the air pump came on sounded like a mini vacuum. before the pump would only make a humming sound and I couldn't hear or feel any air coming from the pump. I just bought an air pump from rockauto brand new a couple weeks ago. my old pump would make the same sound.

There has to be an airflow issue somewhere in there. If the pump is pumping air, then there's something else going on. Either no air is getting through (jammed check valve, clogged tube) or too much air is getting through (check valve stuck open or a leak in the tube).