I hope my post is appropriate here (and I this is my first post, so please be gentle and redirect me if I’m off-base). I know next to nothing about cars, and I’m in a situation where I could really use some informed opinions about an apparently controversial issue of additives. I am considering using a “cermet” type product in my car after spending hours reading about it, but I’m still feeling confused on some things. My situation is that my father left me his 92 Mercedes 300SE which I’m very sentimental about. Money is very tight, and I can’t afford a major overhaul—I would probably have to just sell it instead which would break my heart. Any sound advice would be so much appreciated. Here are my basic questions:
1) I’d like to know if there is any consensus as to which cermet-type product(s) currently available in the US would be the best to try for my issues (description to follow). The more I read, the more products I run across, and apparently some have changed names and have bought other companies out and changed formulas. Is there some basis of comparison I can use to evaluate these products side by side?
2) I just had my oil and filter and spark plugs changed today, so is this a good or bad time to use such a product? I’ve read conflicting recommendations about new versus old oil.
3) Is there any chance whatsoever that such a product could hurt my car?
4) I was also reading about some other types of additives such as Restore. If I decided to try and use one of those as well as which should I use first?
Here’s what I think is relevant background info hopefully:
• 1992 Mercedes 300SE 185K miles. My car uses regular oil and premium gas.
• The engine block was re-machined about 10 years ago after the engine lost oil pressure.
• Over the past few years the idle has become rough and the gear-changing is harsh at times.
• The vacuum modulator was replaced about 5 months ago, but the gear-changing is becoming problematic again. Recently it delays shifting at low speeds like when I pull away from a stop sign, and it seems like it may be starting out in a higher gear. If I shift it out of drive into 2nd temporarily, it immediately starts behaving better. It seems to be OK at higher speeds and once I’ve been driving for a while.
• There’s no smoke, burning smells or noises of any kind, the coolant is clean and it’s not leaking oil.
• I just took it to a Mercedes shop with a good reputation and they determined that the compression was low and extremely uneven. They think that the gear changing issue may be caused by a lack of vacuum created by the engine. They said it may have something to do with the valves or the rings and possibly the timing chain.
I’m not expecting magic, but I’d like to take a chance on a less expensive option like a cermet treatment if I don’t have anything to lose but $75, when diagnostics alone would cost me into the upper hundreds already. I started researching additives because I remembered that my old mechanic mentioned that he was going to add something to my oil that would make it run smoother, but he ran out of time to do it before I picked it up. I hope you can address some of my specific questions listed. Sorry for the long post. Thank you.
1) I’d like to know if there is any consensus as to which cermet-type product(s) currently available in the US would be the best to try for my issues (description to follow). The more I read, the more products I run across, and apparently some have changed names and have bought other companies out and changed formulas. Is there some basis of comparison I can use to evaluate these products side by side?
2) I just had my oil and filter and spark plugs changed today, so is this a good or bad time to use such a product? I’ve read conflicting recommendations about new versus old oil.
3) Is there any chance whatsoever that such a product could hurt my car?
4) I was also reading about some other types of additives such as Restore. If I decided to try and use one of those as well as which should I use first?
Here’s what I think is relevant background info hopefully:
• 1992 Mercedes 300SE 185K miles. My car uses regular oil and premium gas.
• The engine block was re-machined about 10 years ago after the engine lost oil pressure.
• Over the past few years the idle has become rough and the gear-changing is harsh at times.
• The vacuum modulator was replaced about 5 months ago, but the gear-changing is becoming problematic again. Recently it delays shifting at low speeds like when I pull away from a stop sign, and it seems like it may be starting out in a higher gear. If I shift it out of drive into 2nd temporarily, it immediately starts behaving better. It seems to be OK at higher speeds and once I’ve been driving for a while.
• There’s no smoke, burning smells or noises of any kind, the coolant is clean and it’s not leaking oil.
• I just took it to a Mercedes shop with a good reputation and they determined that the compression was low and extremely uneven. They think that the gear changing issue may be caused by a lack of vacuum created by the engine. They said it may have something to do with the valves or the rings and possibly the timing chain.
I’m not expecting magic, but I’d like to take a chance on a less expensive option like a cermet treatment if I don’t have anything to lose but $75, when diagnostics alone would cost me into the upper hundreds already. I started researching additives because I remembered that my old mechanic mentioned that he was going to add something to my oil that would make it run smoother, but he ran out of time to do it before I picked it up. I hope you can address some of my specific questions listed. Sorry for the long post. Thank you.