What exactly goes out on the A/C system of the 92-9? S-Class that requires $$$$?
 

One of the only bad things I have heard about the 1992 - + S-Class is the A/C woe that requires the entire dash to be removed. What exactly is this that causes the woe? - the evaporator? What happens- does it leak or.... ? What if you do not care that much about A/C? Is it something that can go unrepaired if you do not care about A/C? It gets hot here, but A/C stuffs up my nose, so I rarely use it in even in my cars with working A/C. I would just like to have it working to enhance the value of the car. I am asking because as mentioned in another thread, I am considering a 94' S420 and I am concerned about this maybe being a future problem. I may be getting overworked for nothing, as the one I am considering may have already been changed out, or perhaps I can make a deal with the seller (independent MB used dealer/repair). $4950, 1-owner car, black on black, like new, 164K, well maintained.... seems like a good deal? Lastly, what about the timing chains? How often should they be changed?

Thanks!

A/C evaporator leaking is the cause

You either didn't do enough research or don't believe what you read if you think the AC evaporator is the only major item to be concerned with in a W140 :)

Timing chains in the M119 are a little more robust than in the M116/7. General thought is to plan replacement between 150 and 200K. It's a much more involved job because of the DOHC arrangement but with the right tools it shouldn't take much longer.

Get a PPI because there's more that can go wrong than just the evaporator.

If the cam oiling tubes break you'll wear the cam and/or lifters quickly. A ticking noise caught early can save an expensive repair.

Donnie says to walk away from any M119 with sludge under the valve covers. I forget why.

Caps, rotors and plug wires are over $500 a set and tend to not last long enough. SteveB says they can look terrible and work properly but many shops see the telltales of arcing and general wear and replace parts. I generally know my way around engines and it took me over 4 hours to replace these parts in my 95 S420. Not sure what book time is but I expect it's not a $49.95 deal at a tune-n-lube place.

Closing assist pump failure is annoying but closing the doors and trunk harder gets around it. Usually you can adjust the max pressure sensitivity of the pump so you don't hit the cycle time limit that shuts down the pump.

PSE pump failure is worse because you lose central locking and other features.

The stereo sounds great when it works but if it has pops or missing channels it's costly to have the amplifier repaired. The amp and speakers are a matched set so an aftermarket amp pretty much means aftermarket speakers all around.

94 was a bad year for engine bay wiring harness insulation. It's too common for cars of this vintage to have the check engine light to report random failures as a result. A replacement harness is not that expensive but figuring out that's what you need can be time consuming.

$5000 is a great price for a W140 but it could be that the owner is tired of throwing $2000 repairs at it every few weeks.

Sixto
93 300SD

Yes, if you don't care about AC you don't have to repair it.
Gilly

Another possible issue on this car
 

I have seen some interior harnesses biodegrade past safe function.

MB Wiring Harness Failure
http://www.peachparts.com/shopforum/general-information/128181-mb-wiring-harness-failure.html#post927185




Have a great day.

In addition to all of the above...I am having fits with the AC compresssor on my '93 500SEL. Aparently there is a sensor that compares the engine speed with the speed of the compressor. If they don't match the compressor shuts off. So far I have replaced the drive belt and tensioner and the only way that I can get it to work is to keep spraying STP belt conditioner on it every few days. In the spring when I get my income tax refund I plan on taking it in and just telling them to replace the compressor at a hit of $1150 (it's a nippondenso). :eek:

I love my W140, but you do need to have a fairly substantial bank account to keep up with the repairs!

OUCH!

I looked at 140's for a long time before buying. Nearly 3 years of research. My first choice was an early model 300SD until I found out about the issues with the 3.5L diesel engine. I then moved on to wanting an early model 300SE until I found out about the list of problems that the early cars suffer from. If you do the math the savings on the initial purchase are quickly eaten up by repair issues and then your still driving an older model car.

If your going to buy a w140 don't even bother with the early models. If an early model is all you can afford then you probably should not be looking at 140's to begin with as a late model 126 would probably suit your needs much better.

To answer your initial question there were a lot of issues with the early model evaporators that caused them to fail. Many of these issues were finally solved in some of the later model cars. The expense for the evaporator is not the part. Its the labor to dissasemble the many layers of the W140's interior. The 140 is probably one of the highest quality modern MB's made and this works against you when removing the many layers of dashboard and trim in order to get to the evaporator.

If your concerned about money any 140 does have the potential for expensive repairs. If you do your homework and learn about the car you can save a great deal of money on the repair side of the equation. If your the kind of person that looks at their car like a black box and likes to bring it to the dealer and say "fix it" your going to pay for that luxury and then some.

Some people might wonder "is it worth it" to own a 140. My answer is EVERY DAMN PENNY! My car is the most comfortable best driving car I have ever been in and I have driven many newer S class cars and a few Rolls Royce's and Bentleys. Its also the quietest car I have ever been in. The double paned glass and thick door seals do their job well for insulating the passenger compartment from noise. The Bose audio system with its 4 deck mounted subwoofers sounds great and the seats are really comfortable and provide wonderful support for long trips. On top of that I get 23.9mpg mixed city highway fuel economy in my car so its pretty economical to commute in even with having to put in premium fuel.

And there have been no safety recalls on this defective wiring? Thats sad. Even a 5 year old child can look at that damaged wiring and know it is a fire hazard! Sad knowing that the interior wiring is also at risk for that type of failure.

Wow, thanks for the replies. Seems like these cars can be real money pits. You would think that such an expensive car would at least have acceptable wiring systems. :rolleyes:

Thanks for the warnings. Back to Toyota for me I suppose.

Yeah, that seems like one of the big issues on these, as well as the wiring. My question is why in the world did they make the evaporator do difficult to gain access to? Does even the driverside of the dash panel have to be removed? Makes no sense if it does. I remember the evaporator went out on my 90' LS400 and I think it was going to require some removal of the panel, but not all.


Thanks again for the tips. I will probably pass on it.

The entire dash has to be removed down to the firewall. With a high performance car you have additional complexity and higher repair costs. While many people may ***** about the design having the evaporator so close to the main vents allows the A/C to cool really well. I have a black car in the middle of "hotlanta" and my A/C cools my car within seconds of starting the ignition. I have been in many Japanese cars and their A/C is rather weak. My brother's Maxima went back to the dealership many times and they could never get the A/C to cool reasonably. Their eventual excuse was that his car was a dark gray car with a black interior.

Not all 140's have the wiring issues. Just the early ones. Many other car makers have similar wiring issues caused by this same industry standard insulation.

Owning a world class automobile does require a bit of interaction from the owner to provide for the car's needs. Some people are not willing to invest the time needed to educate themselves in how their vehicles work and what they require for years of dependable operation. For owners like this Toyotas are great alternatives. Not quite as nice of a car but certainly a car that thrives on abuse.

I wish you the best of luck on the Toyota and hope that the cheap plastic interior and anemic engine don't bother you as much as they would bother me.

Well no, you buy a new or CPO one.:D 4 year 50k miles bumper to bumper, if it breaks let the dealer figure it out.:cool:

I know a lot of people that pretty much don't know how to check the oil and thye drive a MB. Let the dealer figure it out.

You pay one way or another. A new one is pricey. A certified Preowned is pretty pricey as well. What you don't pay on service you pay in the initial price and in interest and extra insurance (in leases). And of course then there is interest and depreciation on the car because most Americans live hand to mouth and have to finance their cars.

Owners that play that game pay even more because they go from car to car when the warranty runs out. They get hit in trade in value on a vehicle they never finished paying for and have to pay again to get another car. That is unless they are leasing and hopefully they did not go over their miles. :)

I don't mind paying for my transportation especially a comfortable luxurious car like a W140. For some reason people get really bent out of shape over service and repair but they have no problem bending over at the dealership since its "fun and new" and they are getting a "new" car. Even with the repairs of a W140 its cheaper in the long run than a newer 221 or used 220 chassis car if you look at the numbers even including the repairs. On top of that its a superior car in my opinion. Technology asside the neither the 220 nor the 221 have the build quality or attention to detail that the 140 had.

P.S. Not to mention owning a New or CPO MB is even more expensive now since they dropped their "all service is paid" plan. The MB dealer near me quoted me $1000 to change my spark plugs because they were 'special' and required special tools. Have fun keeping that warranty still active and paying those prices for having your services done.

That dealer is on serious drugs if they quoted $1,000 to change spark plugs on and S320. Laugh at them and run away fast.:eek: Or offer them $100 and bring them back to the real world.


I figure owning say a new E350 would probably cost about $1k per month when everything is said and done. If I were ever to purchase such a car I'd put down at least half in order to keep the note reasonable. Figure about $30k down, finance the rest over say 3-4 years.

So all of a sudden that $15k-$20k older S looks like a deal!:cool: Like buying from and outlet store.:D