Changed the O2 Sensor and PCV Valve. Also found my ECTS was VERY loose. Unfortunately still no resolution for my loss of power at hills and other random times. I have a few other issues I think it could be that I'll try. I noticed my valve cover gasket which was replaced about 5 months ago is leaking. I'm going to get a new one and make sure it's done right. Would low oil pressure cause my issues? Good thing about all of this is my car is going to have a ton of new things fixed by the time I figure this out.
Nope, low oil pressure wouldn't cause that. Just remove the damned exhaust from the manifold back and drive it up a hill and see if it bogs down. If not, then you know it's in the cat con, muffler or one of the pipes.
"Only two things are infinite, the universe and stupidity... and I'm not sure about the former."
Charlie, Lake Wales, FL
Thats definitely next on the list. Ill say this, this morning on my drive to work, my car was running terrible. Probably the worst its been. Replacing new O2 sensor for some reason has made my power issues worse. Im not sure why.
After a few days of doing nothing, my car was still running terrible. Seems to get worse by the day. Decided to test the EGR Valve. Unplugged it and drove it. Ran PERFECT!!! First time I remember it being that smooth in forever. Went up and bought an new EGR, came home and replaced it. Took it for a test drive, back to not working right. WTF??? So what could possibly be wrong, where when my EGR is unplugged it works great, but with a brand new one, plugged in, it bogs again. I am baffled and really growing tired of this issue.
I look at the EGR valve as a controlled vacuum leak in operation. That is a vacuum leak allows outside air to be introduced into the intake manifold where the EGR allows exhaust gasses to be introduced.
Early versions of the EGR depended purely on the level of intake manifold vacuum or Ported vacuum to operate them.
Later versions were controlled by valves or solenoids as the computer controls came into play.
At this moment I don't know how Saturn is controlling it, but by the time Saturn was designed and built I am sure it has some form of outside control
I have had engines that unplugging it made no difference, and those that ran like dogs that way. But I'd be willing to bet that what ever is controlling it has it turned on all the time thus creating some form of a vacuum leak only exhaust gas is being introduced when it should not be. If you have a Saturn service book from Chilton or Mitchels or some one look up what controls the EGR valve. And see if it is working as it should. I'm getting ready to go to church and will look up this information later also. And try to post the answer tonight unless of course I forget.
OK, I have gone back and read through this thread from the beginning. as I understand it, you have resolved some issues and now you are either down to this one or you just want to concentrate on this one for now and not get sidetracked by any other issues.
The car idles smoothly, gets good gas mileage, runs good at low throttle such as cruising on level ground and runs good at WOT (wide open throttle). The issue is bogging down under partial load.
The Service Engine Soon light (MIL) is no linger on.
When the engine is cold and when the EGR is unplugged, the engine runs good.
When the engine bogs down, is there a misfire? Does it chug and miss or does it run smooth but simply not produce enough HP for the task?
If it is smooth and the MIL is not on, I would suggest that you get the code reader on and look for a DTC of P0403. This particular DTC is a type D DTC so it does not turn on the MIL. It will also disappear quickly if not detected so you may want to hit a hill just before you go to the parts store to get a reading.
A P0403 means that a voltage is being sent from the EGR to the MAP that causes the MAP to change its output. It is supposed to do this periodically as a test, but only for a half second.
If this code is not present, then I'm afraid you will need to run some tests that require an advanced scanner or computer. One thing that would help is a knock counter. The situation that you are having a problem with is where knocking is typically at its worse. when the knock sensor detects the slightest knock, it retards the timing and that reduces power.
That does not mean that the knock sensor is defective, but it does mean that some diagnostics need to be run from that point. Also the MAP sensor is probably good or the car would run like crap all the time. You may be down to the point of looking for a broken or chaffing wire and those can be hard to locate, and very frustrating.
At least now you are narrowing the field some though.
2002 Silver Blue Special
$9995 with AC and shipping, new.