Using high performance anything on a 20 something year old car with 250,000 miles on the clock is pretty much a waste of money. Something that is high performance is generally matched to other parts that are high performance in order to derive the most benefit from them.
As Kieth has pointed out the method the Saturn uses to generate the spark AND monitor it in order to do two things, be a condition of other functions and to generate error codes is pretty much unique to the S series Saturns. I do not know if other cars use that particular configuration or not, anything I own doesn't. The uniqueness of the ignition system makes it very touchy as to how and why some things work or not.
The factory recommended spark plugs set correctly for the gap seem to be the best spark plug for the car. While I personally am a fan of Champion dating way back and use them exclusively on all my cars including the Saturn, for the Saturn the ones I use are not platinum or any other long life spark plug as the tip design of those types of plugs are different than the regular Champion or the Bosh plugs (I think that is recommended) and that will affect the shape and configuration of the spark generated which can fool the sensing circuit used to generate error code.
Sorry whether I like a platinum plug or not and can argue for the use of one for life expectations, on the Saturn I do not recommend the used of them. Specially if you are getting any kind of an error code related to ignition problems such as one that indicates random miss-fire.
I also have as reference material the professional mechanics version of Mitchel's diagnostics that I am able to tap to translate the error code's into some form of action plan. But with out the error codes to list, there is no way to use this information.
And as far as I am concerned, the Saturn's level of OBD-I logic is a bit hard to actually get error codes as many of the available scan tools today do not recognize it and will not read it out. As I have found out recently while looking for something to buy that is both obd-1 and obd-II. While there are many adequate scan tools available the WILL NOT read the Saturn logic. I have been lucky enough to obtain a professional level scan tool that was excess baggage at a shop I know that has been updated through the late 1900's and as mine is a 1994 I can now read the codes correctly. I doubt I will update it any further as to do so is a 4 digit figure per year of up dates. Of course that does not do you any good, but it sure helps me out a lot.
In any case, I would purchase the regular recommended spark plugs and everyday run of the mill spark plug wires as replacement parts for the Saturn. At least the S series as they exist.
And if you can find something to read codes, publish the codes. The complexity of this car and pretty much anything made from about 1990 on is enough where guessing as to what will fix it will lead to a lot of money spent not fixing things.

Ok, went and got the diagnostic again. Code is P0341. changed the wires and plugs, gapped correctly, everything per the car requirements, still giving me the same issues. Could it be the crankshaft sensor? I have 0 issues starting the car, and none whatsoever when it idles. Just issues on hills, gaining speed, standard acceleration stuff.

Just realized in everything I did, that I did no maintenance to the coil tower. Did not clean it, etc. Should I start with cleaning the 1/4 coil tower or just replace it?

Check it for corrosion and clean it first. Might save you a few bucks. Have you checked for a clogged cat con or muffler? I'm not going to go back through every post, but those symptoms sure sound like a clogged exhaust to me. Cat con breaks down and gets stopped up and can even clog the muffler when it comes apart.

I have not checked for a clogged cat yet. I am still working on correcting the cam code Im getting, however if I do everything to correct that and still have issues, that will be my next step.
Curious if the P0341 is being thrown due to possibly a dirty or bad coil tower, shouldnt this be affecting my car during ignition? I have no issues whatsover starting the car, and again, when it is in idle it will sit there and run smooth as can be. But when I start driving, it just fails to have good power, acceleration, but if I slam down on the gas, itll take off like a bat out of hell, then cruise fine, but as soon as I get to a hill or need to speed up, the issue comes back. I will try taking the coil off and cleaning it when I get home and see if that helps.

P0341 means that the computer is seeing more than one CMP pulse for every two revolutions of the crankshaft. In other words it is seeing a CMP pulse everytime the coil fires.

The causes are:

No voltage on the brown/white wire to the Electronic Ignition Module (EIM). Should be 5VDC +/- 1VDC

More than 15k Ohms on #4 secondary ignition (spark plug and spark plug wire)

Less than 1.5k Ohms on the #1 secondary ignition.

Corrosion in the #4 coil tower. (should cause intermittent misfire)

Crack in the #1 coil tower, arc to ground. (should cause misfire)

Defect in EIM.

Since you don't have a dedicated Saturn Scan tool, the first step is to disconnect the little plug under the EIM, turn the ignition to run (don't try to start) and look for 4-6 volts on pin D (brown/white wire). If it is not present, then check the wire bundle for any short to ground.

This wire bundle runs right up against a metal plate attached to the back of the engine/transmission interface. I would look here for the short. If no short, the problem could be in the PCM. If you don't see one, I would unplug J1 (ignition off) of the computer and then use an ohm meter to check pin D to ground. If no ground, hook up the computer and repeat the test for 5 volts. you may have inadvertently removed the short to ground while moving the wires around.

If no 5 volts and no short to ground, the wire is either broken or the PCM is bad. Find the brown/white wire at J1, pin 26 and check for continuity to pin D.

If the 5 VDC is there, then remove the 1-4 coil pack and inspect it. Look for corrosion and cracks in the coil tower. We call this a coil, but in modern ignition systems, it is actually a type of transformer called an autotransformer. Autotransformer means that the primary and secondary coils share a common connection to ground, it has nothing to do with the term automobile. The transformer providing voltage to your house is most likely an autotransformer.

Anyway if there is any evidence of carbon tracking on the towers, it could be due to a crack or it could have come from a dried out boot on the old ignition wires. after cleaning the coil towers, butter them up good with a dielectric grease. You can get that in little packs at the parts store, get four and butter both ends of the spark plug wires, coil towers and ceramic parts of the spark plug. Do not worry about getting it on the conduction parts, this grease has the property of becoming conductive in a thin film application. You can coat the conducting surfaces of your battery terminals and the battery will work just fine. But it insulates in thick film.

Then clear the code and try again. If the code comes back, the EIM is bad and will need to be replaced. Can you say Pick and Pull?

Ok, so heres what I did and what I found. Pictures attached.

Took the EIM off. Found it to be filthy. Both on the coil packs as well as the actual connection where the EIM meets the engine. Lots of oil,etc. After I got them off, I wiped them down, then scrubbed the necessary metal connections with a wire brush. Got them as clean as I could, reinstalled.

Service Engine Light has completely disappeared, so thats a plus. The con? Still getting some acceleration issues. I am torn on saying whether or not its running a little better. My wife thinks it is. I like to say that it feels SLIGHTLY easier to accelerate but may be saying that cause I know Ive cleaned the dirty components.

Heres what I found after driving all the way to work this morning with no radio, just listening to the car and how it acts. If Im cruising at say 55mph, and I barely push on the gas, I get little to nothing in acceleration. When I push the pedal half way down, sometimes it accelerates normally, sometimes the car shakes lightly, as if it was having a hard time receiving fuel(Thats an example of the feel, not necessarily what I think is happening.) and then when I push the pedal all the way down, the car revs up and takes off with no issues.

Kind of at a stuck point here. Maybe need a new EIM? Check Cat? Any other thoughts? Really appreciate everyones help here, amazing how much I have learned about this car while on this forum.

Edit-At this point Im almost positive its the Cat. It has all the symptoms of it. Whats the best way to check this on a Saturn before going in and getting it replaced?

Edit2-Side note, I replaced me ECTS a month ago while replacing my water pump and thermostat. It was cracked, and replaced with one from O'Reillys, not one from the dealership. Should I have gotten a real replacement part for this instead of a plastic one from the auto store?
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Just to recap the P0341, a cylinder detect signal error (too many pulses.) It is a direct monitor of cylinder #4 and comparison of the signal received there both in amplitude and polarity based on the signal received from cylinder number 1 and sensed as stated from the capacitive pick up plates located under the cylinder number 4 and 1 coils. The polarity checked of the pulses at this time can be determined to insure some form of Noise detection problems that is they come at the right sequence and polarity as compared to the double pulse received from the CKP sensor, spark and fuel timing can be synchronized.
It makes sense that if these plates are impacted with engine crud that they could cause a problem. So it also makes sense that cleaning things up would improve the capability of receiving the proper signals.
However it does point at a possible cam sensor problem as it is used to compare things to do determine proper timing.
The diagnostics pretty much depend on the use of the scan tool for further testing. But that implies the capability of the scan tool to interface with the logic as used on the Saturn and that pretty much says a Saturn factory tool is implied as needed.
Oh well,few people have that capability.

As to checking the catalytic converter for problems? In general if it is plugged the engine will run some what doggy and there will be a tendency to indicate that it is running Hot. And I can pretty much confirm that as those are symptoms I have seen when a converter gets plugged. Also on the Saturn if it is cumming apart you may hear a noise like some one throwing a hand full of pea gravel somewhere under the car. I do not know a good way to inspect a catalytic converter short of removing it from the exhaust and looking into it. It seems to me one end of the converter is easily removed. Easily being an operative. Rust has a tendency alter the definition. Also included if the converter has come apart completely, then all of the converter junk has probably been blown into the exhaust system and probably ended up plugging the muffler.
The one on mine came apart, the front half anyway and it was a tad doggy the car tried to run a bit hot. I did not figure it out for sure until the converter was removed.

It is hard do diagnose a performance problem in a forum format on a car that is heavily dependent on it's electronics to run well. And it is a matter of interpretation too, as to what performance is.
If for all practical purposes, your car runs "well" but down on power that has tendency to be something unrelated to adjustments to the engine as they are now controlled by the computer that runs things. Leaving things like a plugged catalytic converter accompanied with running hot or warm anyways.
The electronics rarely have a failure mode that says it runs well followed by it runs crappy and have that cycle repeated.
The ETC has had a history of causing problems like that but in general ETC's do not cause that type of problem. At least on other cars.
The lack of a proper diagnostic scanner to separate out individual problems and go after them one at a time is another hindrance.
Being able to at least read the codes is a major benefit.
Physical things like vacuum leaks is a problem and the best I can say here is a can of WD40 sprayed around at suspected locations while the engine is running thus causing a change in operation due to sucking the stuff in through a vacuum leak is a classic diagnostic tool.
Your engine cleaning mode is important in that dirt and grim can cause problems too. Most of the sensors have a diagnostic error code that will flag up if the readings come out out of tolerance for the computer that runs things.
The P0341 is in part depending on the Cam sensor to be working correctly in order for the spark timing to be evaluate correctly.
Lacking any other well defined failure mode I guess if the car was mine and i was hopelessly lost and the cam sensor was not hard to replace and I could afford a guess in the dark, I would be inclined to change it too.
Sorry, I just don't know what else to recommend and I hate to make a wild guess based on the information to date and at this time, a guess is all it would be. It is problems of this nature that influenced me to buy a pressure sensing gauge to diagnose fuel pressure at the Fuel Injection. And I have used it rather frequently for intermittent performance problems as fuel presssure is critical on the F.I. engines. In general a fuel pump going out has a tendency to fail intermittently as it approaches the end of it's life. Ive probably gone through about 6 fuel pumps on cars in the last 10 years, all of which caused problems similar to what you are describing. But it is far easier to measure fuel pressure that it is to change a pump by guessing and discovering it fixed nothing.

I don't think it is the cat. If the cat was getting clogged up, you would not have that burst of power at full throttle, in fact that is when things would bog down due to a clogged cat.

If the SES light stays off and you no longer have a P0341 code, then the issue could be due to a slow responding front O2 sensor, but I think you said that you already replaced that.

Next question, when fully warmed up, what is the idle speed. If it is over 950, then I would look for a vacuum leak around the intake manifold, particularly the #1 cylinder. This is a problem with the SL1 engines, I don't know if it affects the SL2 engines but it could be worth looking into.

If the idle is smooth and around 750 and you get good WOT acceleration, I think the next step would be to run a bottle or two of Tecron through the system. If that doesn't work and the SES still does not come on. you might be a candidate for a fuel system flush (AKA wallet flush). These are usually an upsell at many garages when you come in for the cheap oil change special and are generally unneeded, hence the AKA, but once in a while, they actually are necessary and when needed, they do work.

Be sure that if you get a fuel system flush, that they actually hook up the proper machine to the fuel rail and not just dump a can of Tecron in the gas tank and charge you $150. Quickie oil change places are bad about that, as are some unscrupulous garages.

I should add to that the P0341 is probably not the cause of the issues you feel. Generally a P0341 has little or no affect on performance at all. It is possible that the performance issue might clear itself up on its own as the computer gets used to the repair you have done.

Thanks for the info Keith. I actually have not replaced the front O2 sensor so that will be my next fix attempt. I dropped the car off at home during lunch, I will check the idle rate when I get home and post the results of that as soon as I get them.

The idea of........"keeping in reverse with engine on for 20 minutes." has been around for as long as I can remember, and will hurt nothing if nothing is wrong with the tranny. Now if you have a bad Valve body or loose output shaft nut your still going to have that problem when your all done. Both cause reverse slam in the Saturn S-series.

The way I always heard of doing the run in reverse was to do it with your old fluid adding some sort of cleaner and change fluid when done. Then do it again with clean fluid........just be careful I don't want to hear the car fell off the stands and pinned you against the garage wall and broke your legs. That would just suck eggs. Did you here the one about the guy that bought the new Dodge truck that was getting 64mpg. When he brought it in for service he told the dealer about it. When he got the truck back he noticed it was only getting 14mpg on the hiway so he looked under the hood only to find he had a different carburetor on it. The dealer reported the mpg to Chrysler and they sent a field rep over to exchange the EXPERIMENTAL carburetor for the regular one. Last I heard the guy was going to sue Chrysler,Dodge, and the dealership. That was 40 years ago I wonder if the case has gone to court yet.

I have never KNOWN single person that this has ever worked for. Fix the problem and be done with it. This running in reverse popped up on The Saturn Fans forum ran it's course died and a few people reported it to be the best thing since sliced bread. Then after a few known members tried with NO results it died down and just like always people forgot about it and went back to FIXING the problem.

Ya can't put nothing on the internet if it's not true.......

I didnt want to get off topic with another one of my issues, which is non related to my power issues, but the reverse slam procedure I did, actually did fix my car from having issues slamming into reverse, but it still has some transmission issues that I have had for quite awhile. Got a P0731 code, "Gear 1 incorrect ratio" and have some issues with the tranny switching gears. Im assuming bad valve body and once I resolve my power/accelerating issues, plan on having the transmission looked at. Just didnt want to drop the large amount of money I know it will be to fix the transmission when I still have a different problem that I need to resolve.

Just keep in mind that when ever you make a repair or change anything, the computer needs a couple of days to sort through the change and reprogram itself for optimum performance. Have a little patience.

If you have an analog volt meter with a one volt scale, you can probe the O2 sensor wire while someone holds the engine at around 2000 RPM (warm). The needle should sweep about once a second. If it is much slower than that, the sensor should be replaced even if it isn't throwing any codes. If it is sweeping at least that fast, then it is OK. This car uses a generic one wire sensor so they aren't very expensive.

Got literally nothing done last night. My wife took the Saturn and the key got stuck in the ignition. Turned out to be a busted ignition cylinder. Had never had to deal with that before. Thank goodness for Richpin videos. Got it changed in a Walgreens parking lot with no real issues.

As for idling, Keith, it idles in drive at a very smooth 750. Will try O2 sensor today and see if that helps.

The intake manifold gasket is a known issue with the SL1 engine, I just threw it out there to check, but 750 in drive is right on spec. Just remember, if you don't get the expected improvement immediately, give the computer a couple of drive cycles to sort things out. It should improve noticeably in 3 drive cycles but it can take up to ten drive cycles to get completely sorted out and get everything optimized.

You're so right about richpin, Brad. I've seen a LOT of his Saturn videos!

go with denso or bosch for replacement (if you haven't already bought one)

So today I had some time and took the throttle body off and gave it a good cleaning. Man was it filthy.

It did not solve the problem unfortunately but I did notice something that may help you guys in assisting me with a diagnosis.

After I cleaned the TB I took it for a quick spin. The engine was dead cold when I started. For the first quarter mile, the car ran like I champ. I swore it was fixed, was very excited. But after about a quarter of a mile, the issues popped up again and the car bogged bad on a hill near my house, and really anytime I wasnt fully accelerating the vehicle. So something is happening when the car gets to operating temperatures.

The logic level of the Saturn S series computer is some form of a pre-OBD-1 logic. I am not sure exactly what it is, but in trying to purchase and OBD-1/OBD-2 Scan tool the Saturn S cars is one that the tools will not read or will not read well.
It is what is called a Speed Density system in that the outputs or controls are dependent on the Algorythyms written in to it that look at the O2 sensor and the MAP sensor or the position of the of the throttle opening to determine what it is doing. And it switches back and forth between the two sensors in part depending on the engine temperature.
See if you can get the computer scanned looking for an error that flags throttle position or the map sensor or the O2 sensor. I am not sure as of sitting here and writing whether the Saturn uses either the throttle position or the map. My Chrysler based fuel injection which is about the same age uses the map sensor, the throttle body system used on early corvette cross fire systems or the 4 cylinder Vega used the throttle position. These are early OBD-1 speed density systems also
I have some early Saturn Diagnostics and given the chance will look up problems solving diagnostics to see what is mentioned. There are pages of them.

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. :D

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.

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.

Go into the USER CP open signature and add your first name, location, and car info. I've checked it and there are no issues with it. It has to be operator error.

I did that about a month ago. Or was that for someone else?

my mistake...cool...

You need to stop working on the car for a few days and just drive it. Give it a chance to sort itself out.

Alright guys, riddle me this.

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.

Thanks Keith, I will look into that. I went on my lunch break to get more codes read. Prior to me cleaning the EGR I was not getting my SEL at all. Once I cleaned and replaced, it came back on and threw 3 new codes that were not being thrown last time I had it checked.

P0172
P0405
P0134

All seem to resolved around the same issues. With these codes in place, what should be my first step in diagnosing my car? Also appreciate you taking the time to write up all of this info and shoot me some tips. Been a big help.

Side note, I drove it without the O2 sensor last night, with the EGR plugged in and it drove much better than it does with the O2 sensor in.

If you got the code P-134 before you unplugged the O2 sensor, then the sensor is not working. Unplugging the sensor will get you this code. This code is the cause of P0172, system too rich.

P0405 is an EGR code and it could have come from unplugging the EGR valve a couple days ago. It is saying that the 0.35 volts on the sensor wire is missing, which it would be if the connector was not plugged in.

Have you considered buying your own code reader. I have seen them pretty cheap at Harbor Freight tools. If you have a smart phone, there are apps and bluetooth devices that can do a lot of diagnostics for as little as $29 on the internet. I haven't tried any as I don't have a smart phone and i don't want one.

In the meantime, you need to get those codes cleared, you can disconnect the ground terminal from your battery for 40 seconds to do that, hook everything up and drive around for a day, or until the MIL comes on, then get the codes read. Disconnecting the battery might be the best way, it forces the computer into a new learning mode.