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Everything posted by MAC

  1. Take the cover off and they are on each side of the engine. They are not difficult to replace. I replaced mine with Champion Iridium plugs and they are working just fine for well over a year.
  2. The refile plug that needs to be removed is on the driver's side above the pan. The exhaust pipe is in the way, so it's not possible to get at it unless you have a special tool or the pipe is moved out of the way. I drained the trans and then refilled it through the drain plug because it's the only way to get it done without a tool or moving the exhaust pipe. I measured the amount of trans fluid that drained.
  3. I would check the 98 Eldo for engine cradle rust and check the fuel lines from front to back because a Florida car may be susceptible to more rusting than usual, especially if it was driven next to the ocean/gulf. I bought a 94 Eldo and I found this out the hard way when I had to replace the brake line from the firewall back running down the left side.
  4. It's not safe to say the cats are good just because you don't hear anything via the tap test. If the code Auto Zone gave you is either P0420 or P0430 then the converter is not functioning within acceptable parameters. Since you have two exhaust pipes there will be two "downstream" O2 sensors and two "upstream" sensors. The downstream sensors will be located on a CTS on the exhaust pipe at about where the jack is placed--maybe about 6 inches further down, as it monitors exhaust after it flows past the converter. It depends on whether the converters are mounted on/near the exhaust manifolds or further down. I believe the CTS is like the STS in that converters are mounted on exhaust manifolds. If any one of the cats is not working then a code will set (P0420 and/or P0430). While it's possible a downstream O2 sensor can go bad, it's not likely unless you see a code showing there is an O2 sensor problem. Usually, catalytic converter codes indicate bad converters, not O2 sensors.
  5. Attached is a screenshot of what I saw when I tried to check O2 sensors. I'll try to check them again either tomorrow or Saturday. The scanner could see the sensors are 'Present' and detected both are in 'Closed Loop' but could not read any data, which makes me believe I will probably get the same results when I try to check them again.
  6. That is what I was referring to in asking if there was a date code. If there was, MAC would know if it was replaced or not. This is good advice except I'm not sure if the converters will have a stamp. I Googled the topic and I couldn't find a definitive answer. I did come across an article stating California enacted a law effective January 1, 2009, which requires converters to have an identification stamp. One way to find out if yours has one is to go look at it... I'll take a look over the weekend to see if I can see anything. I'll check PepBoys for a mechanics mirror.
  7. That is what I was referring to in asking if there was a date code. If there was, MAC would know if it was replaced or not. This is good advice except I'm not sure if the converters will have a stamp. I Googled the topic and I couldn't find a definitive answer. I did come across an article stating California enacted a law effective January 1, 2009, which requires converters to have an identification stamp.
  8. Hi Jim, Here is what one of the moderators of the forum said: Link to post The part that sticks out to me is the statement that a dealer can "bypass the O2 signal with an ECM modification". When I hooked up my OBDII scanner about a week ago it could not read data coming from either O2 sensor. But before going to the dealer to replace the converters both O2 sensors were putting out data. Perhaps there was a glitch and that if I try again I will see data? I will try again to see if the O2 sensors are putting out data just to make sure. Again, I'm not making any accusations because I would need confirmation the ECM's programming was modified, but this is an interesting statement nonetheless. EDITED: Even though I'm suspicious, I am very doubtful the dealership's techs would get involved with remapping the ECM to bypass the O2 sensors. This certainly doesn't sound like something GM would permit and would thus have to be done without GM's permission. If my ECM is reflashed to make sure its programming is according to original factory specs which, in turn, causes the P0420 and/or P0430 codes to set again and my scan tool is again able to read O2 sensor data, and I can get a printout of some sort showing changes were made to the ECM, then I would be willing to conclude the unthinkable.
  9. I posted at CadillacOwners.com asking, "Is it possible to disable downstream O2 sensors through ECM or PCM?" and was eventually told that dealerships can modify ECM parameters in order to avoid replacing catalytic converters. If you scan the thread you will notice it wasn't very pleasant. I was accused of soliciting information in order to commit a federal offense and accused of making accusations against the dealer. The thread ended up locked at one point but was reopened because I not only vehemently denied that I was looking to commit a federal offense but ended up PM the webmaster and the instigator, dkozloski. I was so upset I called dkozloski a few choice words in a PM and called the webmaster a jerk for closing the thread. I ended up starting a new thread just to deny the allegations against me because I was not given an opportunity to respond. It's a real circus over there as far as my particular thread. I also happened to come across another discussion on this topic at FixYa and there is a post from an individual who also said dealerships can reprogram the ECM.
  10. I inspected the right side (passenger side) downstream O2 sensor and could find nothing indicating tampering. I removed the sensor and inspected it and found nothing unusual. I did not remove the left side sensor because after seeing the right side was good I didn't feel it was necessary. The only remaining thing that I would like to settle is whether it's possible to shutdown or reprogram the ECM or PCM in such a way that it would be possible to effect or interfere with monitoring the catalytic converters in such a way that no codes would set. Given my state of suspicion (as baseless as it may be), I think I'll bring my car to a garage and have the emissions tested to see if anything unusual is detected and whether my STS passes emissions.
  11. This weekend I'm going to inspect the O2 sensors to see if there are any obvious signs of tampering (i.e. a spark plug anti-fouling spacer). If a spacer was used, I should be able to see it. Also, from what I have read on the Internet, some people use tin foil to cover sensors. Since my OBD-II scanner is not able to read O2 sensor information and my cats do not look as new as they should for being less than a year old, which is when I inspected them, I am suspicious that they were not replaced. Actually, I pretty convinced something is wrong but I'm not willing to make direct accusations unless I have incontrovertible evidence. The converters are not new, which should be sufficient enough; however, since I did not inspect them immediately after they were supposed to be replaced, I cannot categorically say they are not new. I'm looking for one more piece of evidence.
  12. I just spoke with another Cadillac dealership for a good 10 minutes and was essentially told (and I’m paraphrasing): 1) It’s highly unlikely that any reprogramming of the PCM would remain for almost a year. In other words, the PCM would eventually override the reprogramming that shut off O2 sensors (for example) and accordingly, if the cats were not replaced, the cat codes would reappear; 2) When work is performed under warranty, GM requires dealerships to send replaced part(s) to GM to confirm the work was needed and as part of the reimbursement process and may use them for testing purposes. Therefore, it is unlikely a dealership would not replace catalytic converters because same must be sent to GM. 3) I was advised that all the dealership will do is check for codes, which means it will not do anything to determine if the PCM has been reprogrammed, assuming same is possible. 4) Interestingly, I was also told that there is nothing a person can do to trick the PCM or by pass the O2 sensors. I refuted this idea by saying that I am aware that people use spark plug spacers to try to bypass the sensors. I was not refuted by the service department rep when I said this, which tells me she was either not knowledgeable enough to confirm or refute it or she didn’t believe I would know about this tactic and didn’t want to admit it’s possible to use a spark plug anti-fouler spacer to bypass an O2 sensor. 5) I will not be taking my STS to this second dealership because I do not feel it will try to address my concerns in a serious way to confirm or refute my belief that my cats may have not been replaced. At this point, I’m thinking that I should take my STS to s NJ inspection station and explain the situation and see if they are willing and able to perform an emission test so I can find out if the emissions system has been compromised in any way that makes emissions testing impossible and whether there is an emissions problem. Also, I may try to contact GM to see if there is a record of the job number on my receipt.
  13. I used to watch CNN quite often but it became apparent as the years went by that CNN became more and more of a mouthpiece for the Democrat Party and liberal ideology in general. I now watch Fox News and will rarely watch CNN only if there is something that interests me--though it will only last about 5 minutes because I quickly get tired of the liberal bias.
  14. I'm going to try to make an appointment with another Cadillac dealership. I think I'll ask to speak to the head manager of the entire dealership so I can explain the situation and gauge the response. If I'm given a run-around or a 'Well...Uhm..." routine, then I will move on to another dealership.
  15. Hi Jim, Thanks for the input. Do you know as a fact that oxygen sensors can be turned off or is it something you've heard? My first guess when I saw that not data was being transmitted from the O2 sensors is that they where possibly disabled through the PCM.
  16. I understand your point of view. Assuming the cats were not replaced, I tend to agree with you that it's very unlikely management is involved. Then again, I'm also not willing to brush aside the possibility. I'm pretty positive the cats were not replaced--though I also don't want to throw around accusations that turn out to be unfounded. So let's say I go to another Cadillac dealership, what should I say? I know of one that is more than 30 miles away, which I have been to in the past. How about I simply ask them to do an emissions test because I want to know if my car will pass inspection? My main concern is that I want the testing to focus on the O2 sensors so the dealership will see the sensors are not providing any data. Chances are the dealership will input my VIN # and find out that I had the catalytic converters replaced.
  17. I'm seriously thinking about contacting the Environmental Protection Agency (EPA) since it is the agency that monitors compliance with the Clean Air Act and compliance with motor vehicle emission standards. I would want to know if there is anything I should do in particular if I suspect emissions system tampering. Here is a link to the EPA's complaint form.
  18. Thanks for the input, Jim. I'm concerned that if I bring the STS to another Cadillac dealer its service department may try to coverup any tampering. I would think that Cadillac dealerships would tend to stick together. If I explain to a second dealer that I suspect the converters were not replaced, I'm doubtful it would want to be put in a situation where it may jeopardize another dealership or it may contact the first dealership and try to figure a way out by doing something to coverup and/or lie and tell me that I don't know what I'm talking about. From what I understand, tampering with an automobile's emissions system is a federal offense, which would be the case if the dealership turned off oxygen sensors and/or installed dummy sensors. I'm not sure a second dealer would want to get involved? Don't get me wrong, I would certainly like to get confirmation of any tampering from a second dealer.
  19. Back in October 2010, GM sent a letter to owners advising that they have decided to extend the catalytic converter warranty until either 200,000 miles or 12 years, whichever occurs first. I posted about this in CaddyInfo's STS forum. Owners who suspect a faulty converter(s) are instructed to bring the vehicle to a Cadillac dealership for diagnosis. If the dealership determines there is a defective converter, it will be replaced free of charge. It just so happens that I was one of the unlucky owners who ended up with a faulty catalytic converter, which I was able to diagnose by using my scantool and ScanXL (standard) software. I did the research after reading the codes and suspected one of the catalytic converters was faulty. Accordingly, I brought my STS to a Cadillac dealership where it was diagnosed as having two faulty catalytic converters. So I made an appointment and had them replaced under the extended warranty. I was told by the service department that it was determined that both catalytic converters needed to be replaced. However, I'm thinking there is a possibility that they were not actually replaced. Let me explain: After they were supposedly replaced, I happened to be in a position to take a look at them while replacing my front brakes. I, of course, jacked the front end up and I decided to take the opportunity to look at the converters which are mounted on the exhaust pipes/exhaust manifolds. What struck me is that they were rusted and looked just like my originals when I inspected them several months earlier. I became immediately suspicious because they were suppose to be only months old in light of the fact that the Cadillac dealership said they were both replaced under the extended warranty. So I became suspicious that maybe they weren't replaced after all and the dealership technicians did a work-around instead. This evening I decided to use my OBDLink (WiFi) and ScanXL software to find out why my check engine light is on, which has been on for a while. I found multiple codes including both oxygen sensor banks not functioning correctly, ECM code, and both camshaft position sensor codes. I cleared the codes and none of them returned (so far) after I did a quick test drive to see if they would reset. I know that chances are they will reset unless they were caused by a freak situation. I then turned to checking the oxygen sensors. I noticed that although ScanXL detects that both are "present"; however, ScanXL is not detecting any numerical figures associated with oxygen sensor data, as none show up in the results colums. All I see are dashes in the columns. Again, before I brought my STS to the dealer, I scanned the oxygen sensors and found that, at that time, ScanXL was reading and providing oxygen sensor data. This evening, after I cleared the trouble codes, I again used ScanXL to take a look at the oxygen sensors and again found no data was being read via either oxygen sensor; however, both oxygen sensors were detected as "present". Question: Is it possible the dealer reprogrammed the Powertrain Control Module (PCM) in some way to shut down the ability of the PCM to read data and therefore not set off catalytic converter trouble codes? In other words, is it possible the dealer shut down the ability of the PCM to transmit and/or read oxygen sensor data in order to prevent the PCM from setting off the dreaded P0420 code? There was one more code that set dealing with the converters? (Please note that I am not making any accusations in this post. I am merely seeking input as to the possibilities. There are many knowledgeable members of CaddyInfo who may be in a position to provide input as to the possibilities)
  20. To my knowledge, GM has not issued an extended warranty for the 2006 model year. If they did, I would think you would have been advised by the GM service department.
  21. If you press the trunk remote button can you tell if the trunk unlatches? You should hear an audible click. Just curious if there is power to the unlock mechanism.
  22. I have yet to experienced anything like you described.
  23. To paraphrase part of the point that you-know-who was making way back when; 'if the gasket fails in such a was as to allow coolant to come in contact with the bolt(s), eventually the coolant will wash away the protective coating on the threads and galvanic corrision will cause the thread damange that is sometimes reported.' Soooo the corrosion and thread damage is a result of gasket failure, NOT the cause of gasket failure. Of course the gasket can fail in such a way that coolant does not contact the bolt(s) and is simply breached into the combustion chamber. There is an active thread on the other forum where the writer took the time to say that all 20 bolts came out "clean". Your point is well taken as far as "the corrosion and thread damage is a result of gasket failure, NOT the cause of gasket failure." If Northstar head bolts were actually pulling because of block threads failing all by themselves, I would think this problem would not be limited to Northstar engines unless someone can show that GM did something wrong when it came to block casting, thread pitch, bolt length, or something else. The Guru made it clear that Northstar head bolt length is well over necessary tolerances in order to prevent separation. As far as claims that head bolts were actually loose in the head, I have yet to see any evidence of same. I have also read a post where someone claimed a GM mechanic told him that bolts were pulling because of thermocycling. REALLY?! I remember some time back some attorney was trying to assess the possibility of suing GM in a class action lawsuit over alleged head bolt failure but apparently nothing was filed. My point is that there seems to be a lot of speculation but no proof concerning head bolts allegedly pulling out of the head. I owned a '94 Eldorado up until 230,000 miles and there was not one sign of head gasket problems. I didn't neglect the antifreeze and did plenty of WOT with the engine well over 200K miles.
  24. I remember reading a long discussion about this topic on the Cadillac Forums website when the Guru was around and he explained how head bolts are encased in order to protect them from coolant seepage. He said those who claim head bolts actually pulled or separated from the head are actually seeing the results of damaged threads caused by removing the head bolts in order to replace the head gasket, which is why Time-Serts are necessary. I've seen many parrot the pulled head bolts claim, yet no one has provided any proof. The Guru did say that the head gasket is a week point and that eventually it could fail due to thermocycling. Here is a link where Poobah mentioned thermocycling back in 2007 and in post #6 I also mentioned what the Guru discussed.
  25. I have one question: Has anyone actually proved that Northstar head bolts pull or separate from the block? It seems to me that claiming Northstar head bolts pull and therefore cause head gasket failure is an unsupported theory. I have yet to see anyone post any proof.
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