MAC

Cadillac needs a gas/electric hybrid like the Lincoln MKZ Hybrid. I recently bought a 2011 MKZ Hybrid. Very nice, but it does lack a few features my former '05 STS has, such as: 1. You need a key to unlock and start. There is a keypad; however, it is really nothing more than a backup way to unlock in case for some reason key is locked inside. I have to physically lock door because it does not have automatic door locking system and no fob that allows easy access; 2. THZ audio system is not as good as Bose; 3. I like Cadillac's navigation British lady who gave me driving directions. The MKZ navigation voice feature is not the most warm and friendly sounding. Also, if you deviate from the set navigation route it may not reset navigation based on current location. This, to me, is a major issue with Ford's navigation--at least this is my experienced based on a trip. Luckily, I knew where I was at, so I ignored navigation and cancelled it. 4. The MKZ has slow acceleration given it has a 2.5L coupled with an electric motor for a total of only 191 hp. Then again, I am getting over 35 mpg, so this is the obvious trade off; 5. Trunk is smallish because battery pack is located behind rear seat; Overall the MKZ Hybrid is a nice car. It gets good reviews. In 2013, styling was changed to the current version which does not get any better gas mileage then the 2011, which was the first year for the MKZ hybrid. Cadillac needs to catch up by developing a semi-luxury or luxury gas/electric hybrid like the MKZ.

By the way, maybe the problem is the amplifier. Did you try removing positive and negative battery cables and touching them together to reset electronics? This was one suggestion I read about radio problems that may or may not work. It seems to me that your best bet is to try to figure out what the problem is with the original radio.

Here is a link to a website that fixes Cadillac OEM radios. Cadillac Bose Amplifier / Speaker and Stereo Repair Here is a link to same website's homepage: Factory Car Stereo Repair, Inc. I suggest you call and/or submit a request for a quote to see if your radio is one that can be fixed. It may be something minor. No power and glitching out may be nothing more than a defective switch. You will never know unless you give it a try.

I would see if the radio can be fixed. When the dealership told you the radio was no good were you given a specific reason? Was there a trouble code, such as a communication code or something that could be related?

I'm not sure what the problem is with the original radio but here is a link to a short discussion about the 2008 CTS radio and one possible fix. It seems the best way to deal with this situation is to fix the radio.

Below I quote information I found regarding the 3.6L CTS engine, which says it is indeed an interference engine:

If radio fuse is removed and then reset anti-theft, maybe it will start. Below is a procedure I found for resetting anti-theft: 30 minute GM relearn procedure: 1-Turn ON the ignition, with the engine OFF. 2-Attempt to start the engine, then release the key to ON (vehicle will not start). 3-Observe the SECURITY telltale(this is the security light), after approximately 10 minutes the telltale will turn OFF. 4-Turn OFF the ignition, and wait 5 seconds . 5-Repeat steps 1 through 4 two more times for a total of 3 cycles/30 minutes (the vehicle is now ready to relearn the Passlock(TM) Sensor Data Code and/or passwords on the next ignition switch transition from OFF to CRANK). IMPORTANT: The vehicle learns the Passlock(TM) Sensor Data Code and/or password XXXXX the next ignition switch transition from OFF to CRANK. You must turn the ignition OFF before attempting to start the vehicle. 6-Start the engine (the vehicle has now learned the Passlock(TM) Sensor Data Code and/or password).

I'm not speaking from personal experience; however, from what I have read, you would have to take it to a dealership for ECM programming, so it will recognize the replacement radio.

I did some research on this topic. From what I saw, it appears that intermittent radio and/or loss of navigation indicates a problem with the radio or a problem with one of the pins at the harness. I will see if I can find it and post either a link or quote it. But one person said that it was narrowed down to a faulty pin at the harness connection.

I haven't tried adding upper engine cleaner. I have used Marvel Mystery Oil figuring it may clean internal parts including rings. I also did a bit of research and someone said 15W40 did not increase oil pressure--at least anything worth noting. As far as 20W50, that may be a different story?

If it's better to use 10W30, then I will use it. I just want to curb oil burning and hopefully oil leakage. I am now looking to maybe buy a STS AWD-V8. I have been looking for a few months. But I have said that I want to run and run the STS I have until it can't run anymore. But the V8 Northstar in it just keeps going and going. If I solve the oil leaking chances are oil use will be cut quite a bit. I just haven't had the time to get underneath and see what's going on with oil pan bolts--maybe they are loose. Then again, oil leaking is a problem with these cars, so it is likely that I need to replace several gaskets, especially with almost 300k miles.

I drove almost 800 miles over Labor Day and, so far, no issues. Thanks Jan. I will probably use either 15W-40 or 10W-40 during winter.

I decided to give 20W-50 oil (Mobile 1 Full Synthetic) a try in my '05 STS. I'm dealing with leaking, plus no doubt burning oil with almost 300K miles. I know that some will tell me that I am looking for trouble; however, my high mileage engine no longer has tight tolerances, so this heavier weight oil should lubricate. The oil pump should handle it. I recently put in 4 quarts of 15W-40 and it seemed to me the car ran better. Probably less oil burning helped? I will see how it goes, particularly if I have to top off less. Between oil leaking and burning, I was topping off too much. In fact, it was almost like not necessary to change oil because I was topping off so often. I changed oil today and used almost all 20W-50, except for about 1 quart of 5W-30, just to get rid of it.

Traction control is very sensitive--actually, too sensitive, in my opinion. It can be downright dangerous on roads that are not smooth because hitting a rough patch during acceleration will cause traction control to engage causing brakes to engage. Many times I have been annoyed by traction control. I would not be surprised if a bad mount would cause traction control to engage since engine hop would likely effect suspension and trick the computer to think something was going on traction-wise.

I have almost 300K on my '05 and it runs real good. However, there are issues as follows: 1. Oil leaks; 2. Power steering pump is susceptible to failure (A pain to replace but a home mechanic can do the job); 3. Rear differential bushing will eventually fail causing clunking sound, which means it must be replaced. 4. This particular design can eat batteries due to too much heat since it is placed at the rear near at the passenger side firewall. I finally insulated the battery after going through 3 of them in about 4 years. 5. If you have different size front and rear tires this means no rotating of tires. Accordingly, rear tires tend to wear more quickly than front; 6. Watch out for rust at the front of the frame rails. The side walls of the rail may look good but are rusting. 7. Intake manifold bolts are susceptible to loosening causing vacuum leaks and trouble code(s); 8. Shift linkage is eventually going to fail; 9. 17-inch OEM aluminum wheels are weak and susceptible to pothole damage in comparison to the 18-inch wheels. 10. Every time brakes are replaced check all metal parts for rusting and coat them with paint because though the '05 STS has good rust resistance, suspension parts will eventually rust. Don't ignore rust!