P0133, P0137, P0141, P0341, oh my!

[Dan400Man]

No particular symptoms, and the "Service Engine Soon" light was sporadic until recently. Finally stayed on and was able to get over to Auto Zone to have them pull the codes. Car's got 179k miles and the last tank got me just over 31 MPG with mixed city and highway driving (which is 79 MPH on cruise); I usually get around 33-35 MPG in the summer.

I found http://www.obd-codes.com/trouble_codes and looked up the codes. So, I know the first three codes relate to the oxygen sensors, and the last one relates to the camshaft position sensor.

Reading up on the oxygen sensors, I was told two months ago that the exhaust pipe between the manifold and the cat converter was getting close to leaking. I haven't really noticed the exhaust being noisier since then, but could a small leak cause the O2 sensors to go wacky? Also, before I spend money and effort replacing the sensors, is there a way to test whether the cat converter is plugged?

Re exhaust leaks: Is there a general consensus of how well those exhaust repair "wraps" work?

Re the camshaft position sensor, the one thing that stuck out in the information was "NOTE: this code can also be set by extended cranking periods." Almost since the day I started driving this car, I've had sporadic occasions when the car won't start on the first crank. Advice given here a few years back was to turn the ignition to "on" without starting, to give the fuel pump a chance to do it's thing (pressurize?) That works well for the most part, but I have had a few occasions where I do that and the first crank doesn't start the car, and I stop cranking for about five seconds and start again; almost always the car will start.

Where should I go from here?

[SCpunk2001]

Hey there,

I believe code P0341 is a general OBDII code for GM camshaft sensors, however Saturns don't use a camshaft sensor -- the PCM reads input from cylinder 4. The code is generally caused by a misfire in cyl 4 (plug, wire, coil etc). This is what I've come to understand anyway.

Hope someone else can help with the other stuff.

[SCpunk2001]

I did a quick study on the other codes. They are related to the front 02 sensor. It is luckily a cheap sensor and in a terribly easy place to get to. On the exhaust manifold, in front of the radiator, you'll see the sensor with wires coming out. First, check the wires to make sure they aren't corroded or torn. If they aren't, assume the sensor has gone bad. Again, its cheap and easy to replace. Don't get any oil on it while replacing, because it will give a faulty reading. Afterwards, go to Autozone and turn that SES light off. This hopefully will fix your problem. I'd make a bet that your misfire and the 02 sensor going bad are related. A tune up and an 02 replacement should fix this problem.

[adventureoflink]

there's a way to test your front O2 sensor using a propane torch; it's in the S-series new/returning owners' checklist in S-series general. although your codes altogether would point to bad O2 sensor (O2 circuit Slow Response, O2 sensor Low Voltage, O2 sensor Heater Circuit Malfunction; all codes are on Bank 1), it's best to test the sensor to be sure. at 179k miles on the original sensor, it may simply be wore out. When replacing the front O2 sensor, be sure to use NGK/NTK or Denso DIRECT FITS; DO NOT use universal and/or cut-n-splice BS in general.

P0341 is a generic code that should be supported on ALL OBD-2 equipped vehicles, NOT just G.M. and not just the S-series in general.

Auto Zones and the like won't reset the codes because it's illegal (even in a place that doesn't do smog checks ).. your better bet is to pull the PCM-B fuse in the underhood junction box and leave it out for about a minute or so. This'll reset the PCM and the codes.

Although most cat restrictions would be reported with power loss, there's two ways to test for a plugged cat: one is to remove the front O2 sensor and go for a drive. If the car has restored power, then there ya go. Otherwise, BANG on the cataclyctic converter and listen for rocks inside.

more information on your codes:

http://www.obd-codes.com/p0133
http://www.obd-codes.com/p0137
http://www.obd-codes.com/p0141

[Dan400Man]

Thanks for the quick reply!

Funny you mention getting AutoZone to reset it. I asked the manager who pulled the codes to do that, and he said he couldn't do that anymore, liability issues. Apparently there was a lawsuit...

Re the P0341: Makes sense. The AutoZone guy tried to pull up a camshaft position sensor for my vehicle, but the puter came up empty. Again, tho, performance doesn't appear to have suffered. I replaced the plugs and wires within the past year, although I used Bosch platinums (before I read here that they were not recommended on my car). Maybe I should just replace the plugs with what I saw recommended here, and be done with it.

Re the O2 sensors: Two of the three codes point to exhaust leaks as a possible cause. I was thinking of plugging the leaks and resetting the codes to see if that caused the P01** codes, before I spend money to replace otherwise good sensors. Also, I was told that the front sensor is likely to be a tough beast to get off if it was the factory original. If I'm able to resolve the code without spending hours trying to get the sensor off, well...

Re the whole performance issue: Part of the problem I have with assessing performance is that I don't notice really minor changes over long periods of time. Is my car sluggish? Or is the better question: Is my car, with 179k miles on it, performing as well as expected?

[adventureoflink]

Originally Posted by Dan400Man

Thanks for the quick reply!

Funny you mention getting AutoZone to reset it. I asked the manager who pulled the codes to do that, and he said he couldn't do that anymore, liability issues. Apparently there was a lawsuit...

Probably, but as I said, most likely it's because it's illegal (even in a non-smog testing state).

Originally Posted by Dan400Man

Re the P0341: Makes sense. The AutoZone guy tried to pull up a camshaft position sensor for my vehicle, but the puter came up empty. Again, tho, performance doesn't appear to have suffered. I replaced the plugs and wires within the past year, although I used Bosch platinums (before I read here that they were not recommended on my car). Maybe I should just replace the plugs with what I saw recommended here, and be done with it.

there was your first problem: using Bosch and Platinum. Those two words + S-series = should never go in the same sentence. Yes, DO get the NGK coppers.

Originally Posted by Dan400Man

Re the O2 sensors: Two of the three codes point to exhaust leaks as a possible cause. I was thinking of plugging the leaks and resetting the codes to see if that caused the P01** codes, before I spend money to replace otherwise good sensors. Also, I was told that the front sensor is likely to be a tough beast to get off if it was the factory original. If I'm able to resolve the code without spending hours trying to get the sensor off, well...

If it helps, get the engine fully warm (when the coolant temp gets to 1/2 mark) and use a 7/8" long handled open-ended box wrench to get at it. I would also get the sensor off anyway, to visually inspect it for black caking, cracks, etc. And the only way to test for an exhaust leak would be to start on a cold engine and feel around the exhaust manifold, piping, connector between the exhaust manifold and downpipe, flexpipe, and the catcon for leaks. Oh yes, exhaust leaks can cause your sensor to go all wacky too (don't ask how I know ).

Unfortunately the heater malfunction would either point to the sensor itself, or something electrical.

Originally Posted by Dan400Man

Re the whole performance issue: Part of the problem I have with assessing performance is that I don't notice really minor changes over long periods of time. Is my car sluggish? Or is the better question: Is my car, with 179k miles on it, performing as well as expected?

As of right now your car is either dumping more fuel in the system or putting less fuel than expected due to the four codes being set. That camshaft code can also cause a mis-start, due to it having to "guess" which cylinder it's going to fire on.

Just so ya know, anytime your Service Engine Soon light is on and the engine is running, you are polluting 1.5x more than the federal or Calibfornia (depending on programming) standards. Which means, depending on the code, your car will enter a limp mode (P0341 will do it for sure, I believe the O2 codes do it as well).

[spud42]

Originally Posted by SCpunk2001

I did a quick study on the other codes. They are related to the front 02 sensor. It is luckily a cheap sensor and in a terribly easy place to get to. On the exhaust manifold, in front of the radiator, you'll see the sensor with wires coming out. First, check the wires to make sure they aren't corroded or torn. If they aren't, assume the sensor has gone bad. Again, its cheap and easy to replace. Don't get any oil on it while replacing, because it will give a faulty reading. Afterwards, go to Autozone and turn that SES light off. This hopefully will fix your problem. I'd make a bet that your misfire and the 02 sensor going bad are related. A tune up and an 02 replacement should fix this problem.

^
unheated One wire sensors should be inspected every 30,000 miles service life 50,000 to 90,000 miles they age, wear out or get contaminated and can be
inaccurate long before they fail in other words its like having 179k on your sparkplugs
well 90,000 on our car
7/8" box wrench and came right off
Luckily My 1997 SL2 had the fuel pump changed years ago under warranty
At 180k my coil started to fail cleaning helped but right after came across a nice used one
haven't had a pending P0341 or p0300 since

[Dan400Man]

I'll get the NGK coppers tomorrow. What gap should I use?

Originally Posted by adventureoflink

there's two ways to test for a plugged cat: one is to remove the front O2 sensor and go for a drive. If the car has restored power, then there ya go. Otherwise, BANG on the cataclyctic converter and listen for rocks inside.

Sorry for being a newbie on exhaust, but just so I'm understanding this: If the car has restored power after removing the front O2 sensor, then the problem is the O2 sensor, correct? Also, if banging the cat converter and you don't hear rocks shaking, that's indicative of a plugged cat converter?

Can an exhaust leak damage O2 sensors? If yes, then I want to resolve the leak before I replace the sensors.

Originally Posted by adventureoflink

That camshaft code can also cause a mis-start, due to it having to "guess" which cylinder it's going to fire on.

So, it could well be that the camshaft code is related to the O2 sensor codes, eh? Automotive symbiosis?

Also, I'll take your advice on testing for leaks on a cold engine. If I find leaks, do the "repair wraps" do any good? Or should I be looking to replace the offending part(s)?

[alordofchaos]

Originally Posted by Dan400Man

Sorry for being a newbie on exhaust, but just so I'm understanding this: If the car has restored power after removing the front O2 sensor, then the problem is the O2 sensor, correct?

Pulling the front O2 sensor is a way for testing for plugged exhaust.

No O2 sensor in there gives the exhaust a route to escape, if there is a restriction between the engine and the tailpipe.

[Dan400Man]

Because I had to travel out of town the past few days, I haven't been able to do anything about resolving the codes, and I have been driving our other car. When I got back home and drove the Saturn this afternoon, the SES light didn't come on. Does that mean that the problems are gone, at least for the time being?

I still plan on checking for exhaust leaks once the car cools down.