Hello! My name is Donna and I am having a problem with my 1991 Mercedes 300E with a 3.0. litre engine. I will be as detailed as possible in describing the problem and history. My car has about 79,000 miles on it now. It is a fuel injected system (you probably know this). Now, I drive this car locally only 1 - 3 times a week, and this is how it has been driven for the past 3 years -- very little. I have regular oil changes and the last heavy duty maintenance was supposed to have been done by the Mercedes dealer right before I bought the used car from them in 1995 when the car had about 59,000 miles on it. I had asked them to do the 60,000 mile work on it before I would buy it, to save me money since the car was close to needing that work as far as the mileage goes. So, the dealer said they did the big maintenance work on it (I relied on and trusted them to do what they agreed to), and only oil changes have been done since then because, as you can see, I haven’t driven it very much in the last 3 years.

The intermittent problem began last summer when it would start up find upon first starting it for the day. But then, after driving it less than 3 miles and turning it off, I would come back to my car to restart it and get on my way, and it would turn over but be very hard starting. After multiple attempts and flooring the accelerator, it would again start and it would be find all day. There was never any fuel smell as this happened. Once or twice last year, the car stalled momentarily while I was driving. I brought the car to a repair shop, but they said it might be vapor lock and that I should always keep the car fuel tank full. Other than that, they said I should drive the car until I can't drive it anymore and it breaks down and then they could find the problem better. I resigned myself to this, as I cannot afford to have parts replaced without knowing for certain that such parts will solve the problem. I did have the spark plugs changed and, of course, an oil change (even though the car is driven little). But the problem -- although intermittent -- continued.

That brings me to this year. The intermittent problem continued, but now it has changed a bit. The car is hard starting the first time I start it up for the day, rather than being hard starting the first time I restart it after having driven it less than 3 miles. It also runs a very rough idle for a few minutes (the front shakes and vibrates) before it returns to normal. It also sometimes stalls once or twice or three times in a row after first starting. But, in the end, I do get it to start. So now, I have a problem starting it in the driveway at first. It always starts, but usually takes a while. A few weeks ago, another problem appeared, but perhaps it is not related. The ASR light came on and I noticed a definite reduction in power as my car booklet says will happen. But the next day, even though the light stayed on, the car was running fine with no reduction in power! I was surprised to say the least! Being low on money, I did not take the car to get it checked, hoping that the light would go off. What happened after 2 weeks or so, was that one day I went out to start my car and it was totally dead. My battery (having already been once replaced with a 60 month battery in 1996), would not take a jump, so I bought a new 60 month battery at the end of May. My spark plugs were also changed for a second time within a year – but they were okay – no problems on them, it was just a precaution. At the time, my alternator was checked and it was fine. But I noticed now that not only was the ASR light on – but the ABS (antilock brakes) light was on as well! The shop that replaced my battery said that the 2 lights were on because of the battery going completely dead (even thought the ASR light had come on a few weeks before). But the shop said the codes could be reset but they did not have that machine to do it.

Yesterday, I brought the car to a shop that said thought they had the equipment to reset the codes and they also said they would look at the car to see if they could find out why it acts as it does, but then they realized that they didn’t have the exact software for this Mercedes! Also -- because the car was running fine by the time I had arrived at the shop (I had trouble starting it and then a rough idle, but both symptoms were fine when I got to the shop -- they said there was no sense in hooking the car up to whatever other testing equipment they were going to use because the car sounded fine and nothing would come up on the equipment. They also said I should drive it until it breaks down unless I wanted to play and pay for a guessing game of replacing certain parts! While I was there, they did replace the fuel filter, but it seems to be running the same. But this repair shop said that from the symptoms I described, it sounded like a possible problem in the fuel system, a fuel pump or whatever. They said this because they said if the car is hard starting and rough idling, but clears up – then it sounds like the fuel system. I told them I had put in a bottle of stuff that is supposed to clean the fuel injectors last year and I put in another bottle just a few days before. They added that a problem with the fuel injectors in the Mercedes is basically unheard of, so they didn’t think it was the injectors. But again, they said to drive the car until it breaks unless I can afford otherwise, which I can’t. So now I am worried because I cannot afford to bring it to the dealer who may know what this problem is. But I am equally scared at getting stranded on the road in case it breaks down!

I am told the ASR and ABS lights have nothing to do with the hard starting, stalling and very rough idling problem. One shop said both lights are on because of the battery dying. Again, the ASR light is on but the engine output reduction problem went away the next day after it first came on! The only other problem I had was in 1997 when the car starting stalling first thing in the morning as I stopped at the first few stop signs. It was under warranty, so I brought it to the dealer who ended up replacing the throttle actuator (they also mention a throttle slide and a switch, I don’t know if these are all just different terms for the same part?). Later on, I found out that the part was actually recalled by Mercedes Benz and somehow I was never notified. Even though the problem I am having now is a bit different, I am adding this information in case anyone may think that perhaps it is related, maybe the replacement part is also bad. Or perhaps they did not replace all they should have. I just don’t know. In addition to this web site, I keep checking the National Highway Transportation Safety web site for problem notifications since that is also where I discovered that the throttle linkage problem was one that should have been fixed on my car before I bought it, as it had been recalled in years previous to my buying the car.

Thanks for any guidance anyone can provide. Double thanks for reading through all this to this point! I am desperate money wise. I want to have the car fixed before it breaks down if I can, but I have very little money to spare. I am told that I should sell the car after I get this fixed, because fixing it in the future for anything will be too expensive. Why did I buy it then? Well, I bought it at a time when my financial situation was very good.

I completely empathize with your problem. I have a 300CE parked in my garage right now, and had the same problems as your car did. Now it won't even start at all! Anyway, your problem could be the OVP relay behind your battery. To learn more about this part, use the "search" function on the upper right hand of this page, and type "OVP". You can also bring your car to the dealer and have them check your relay for you. Good luck!

__________________
89 300CE
91 Supercharged Miata
99 E320 Wagon

Donna:
The OVP is a $50-70 part through Fastlane at the top of the page, and is easy to replace yourself - it just unplugs! It is a surge suppressor for your car's computers and electronics. I would read about OVP in the archives / search, and have it checked at the dealership to make sure, but your car seems to have the same symptoms as many others in the past.

Regarding the expense to maintain, while there are certainly lemons out there for every car ever made, I have found my 300E to be more reliable and MUCH less expensive to repair than my Acura Legend. Good luck

__________________
John

2003 Firemist Red/grey leather SL 500
2015 Palladium Silver/black mbtex GLK 350
1987 Smoke Silver/burgundy mbtex 300E Sportline (SOLD)

Click to see 87 300E

Donna,
I don't have any solutions for your car troubles, but I do have some advice to offer. Driving a car for three miles and shutting it down is the worst possible thing for it. The engine and all it's fluids have barely warmed up. In your situation, you should be changing the oil more frequently then the recommended interval, I'd say every 2000 miles or so in your case. Also, three miles is probably not far enough to re-charge the battery to the level just before you started it...which is probably why your battery is not lasting as long as it should. The ABS and ASR lights are probably coming on due to low voltage caused by your very short commutes.

Very short drives will cause almost all the mechanical systems in your car to deteriorate faster than normal. Also, the exhaust system will tend to rust out sooner as it accumulates moisture that would otherwise be vaporized with a fully warmed engine.

If at all possible, try to take your car for a good long drive at least once a week. The engine needs to get to operating temperature and stay there for at least a half hour. Also, try to use a good quality fuel, if not every tank full, then every other or every third. Something with detergents to keep the fuel system clean, ie. Chevron with Techron.

I think you will find that your car will run better if you drive it more. Best of luck.

__________________
Glen Tokuhara
Beauty & the Beast and the wagon that could!

Donna,
I would definitly change the Overvolt Protection Relay (AKA: OVP). General symptoms of this are the difficult warm engine starts, stalling and ABS light (could be ASR too in your situation.).
Do what JCE said and definitly change the OVP and purchase through fastlane or partsshop (at the top of the page), cheapest of anywhere.
Good luck and let us know how your problem turns out.

__________________
2006 E350 w/ 155k miles (Daily Driver)

Previous:
1993 300E 3.2L Sedan w/ close to about 300k miles
2003 E500 Brilliant Silver (Had 217k miles when totalled!)
1989 300E with 289,000 miles (had for <1 yr while in HI)
03 CLK 500 cabrio (Mom's)
2006 C230k (Dad's)
1999 S420 (Mom's/Dad's)
2000 C230k Sport sedans
2001 CLK320 Cabrio (Mom's)
1995 C280 My First Mercedes-Benz... (155k miles. EXCEPTIONAL AUTOMOBILE. Was Very hard to let go of!)

Donna: I've fixed alot of the warning light problems and stalling in traffic problems with the overvoltage protection relay also. You'd have to be pretty handy to replace it yourself, though. It is attached to a bracket with a nut and bolt and is rather inaccessable, not "buried" really, but not as simple as pulling it out either. I usually take the battery out to replace it, or else the battery "fights" you every step of the way. I'd give it a try.
The rough start sounds like the valve stem seals are seeping, causes a problem just like you are saying is going on. The seals harden with age, or else wear out. With your car, I'd say it's age. It's not a terrible job to get done, probably the best part of $500, though.
This recall you mentioned (at the NHTSA website) for the throttle cable bushing was important to have done, but not part of your concerns at all. The old bushing was rubber and would get soft and allow the throttle to become disconnected, a real safety issue since it was more likely to occur at more heavy throttle applications, like when you pull away from a stop, could happen at very inopportune times, as anyone can imagine. The new bushing is plastic and I've never seen one fail.
I'd look into getting the OVP relay checked, there is a particular part number and country (Austria, I belive) of manufacture that are affected, and have an updated part number to replace it with. The valve stem seals could wait, it won't make the car up and die or anything.
Gilly

Donna:
Sorry about the mis information on pulling the OVP, I assumed (always dangerous) that your 91 would be as simple as my 87 300E. When you look for a shop in the San Diego area (I think that is where you said you were located), a number of members have posted about their favorite or least favorite shops in different cities. The list of shops in SD is at the link http://www.peachparts.com/shopforum/showthread.php?threadid=3562 Good luck!

__________________
John

2003 Firemist Red/grey leather SL 500
2015 Palladium Silver/black mbtex GLK 350
1987 Smoke Silver/burgundy mbtex 300E Sportline (SOLD)

Click to see 87 300E

If you are in San Diego, give Exclusive Motors a try. Call Pat for an appointment and you won't be sorry.

__________________
Regards . . . . JimF
-------------------
'94 S500 Cpe

Visit my Mercedes Web Page

Hi Guys! Thank you so much for all of your kind replies. I really appreciate them. :-) I have read them all and I have done some scant research on some of the suggestions. I now have four observations/questions:

(1)a. I never buy anything but premium unleaded gasoline and have the oil changed on the car once a year (even though my oil is as clean as can be because I drive it now < 300 miles or so a year!). I am confused that with this being so (and I presume that the prior owner also did the same), why should there be such a carbon buildup at all.? Afterall, the car has only 79,000 miles on it. Have I been cheated at the gas pumps? I will, however, now only fill up at a Chevron dealer (a little bit out of the way for me, but from what everyone has said, it is worth it).
(1)b. I have also added fuel additives over the years (not Chevron Techron) to clean the engine and injectors, but I just bought 2 bottles of Chevron Techron and will add these as soon as I am down to 1/4 of a tank. Should I add both bottles or do one bottle and fill up; then wait until I am down to 1/4 tank again and then add the other bottle?

(2) Because of the variety of suggestions and my scant financial resources, I think my course of immediate action in addition to adding the Chevron Techron will be to bring the car to a repair shop that can read any codes that may be stored in the computer. It is my hope that doing this will also reset the computer (and perhaps those darn ASR & ABS lights will go out). I do not think that there is anything wrong with both systems because there is no decrease in engine power or braking action. Am I right in thinking that the right repair shop (I live in Suffolk County on Long Island, NY) must have the LAMBDA software? I ask this because one shop said they could bypass "things" and reset the codes/computer...

(3) I just noticed that my car door open "chiming" has not been sounding at all. The other sound when one puts the key in the ignition is still working -- you know the one that is like a super loud constant buzzing. My horn/car alarm still works too. I looked at the fuse box under the hood, but I cannot identify any fuse that relates to that chime. Nor do any fuses in the box look bad. Any ideas what could cause this to happen? How to fix it? Is this perhaps related to something else...

(4) I will strive to drive the car for at least a half hour to an hour straight once a week. I am afraid to admit that in the past three years, I have driven it for 5 minute or so increments basically -- local stop and go; run errands.

Donna,

You should have your oil changed twice a year, whether you go over 3k miles or not. Time degrades the quality of the oil just like driving it does.

I would also immediately purchase a new OVP and put that in. It will hopefully (and more than likely) clear up many of your starting problems, and the ABS and ASR light.

I would also drive the car for ATLEAST 1/2 an hour like you said you were going to do. But be sure that when you do, you punch it. I mean floor it from a stop all the way up to speed. Of course, do this as conditions prevail. But if you give your car a good hard drive (AKA an Italian Tune-Up), you will burn off a lot of the carbon and other crap that has built up. So drive for atleast 30 minutes and really give it a good run. These engines like that!!

Good luck and keep us posted!!!

__________________
2006 E350 w/ 155k miles (Daily Driver)

Previous:
1993 300E 3.2L Sedan w/ close to about 300k miles
2003 E500 Brilliant Silver (Had 217k miles when totalled!)
1989 300E with 289,000 miles (had for <1 yr while in HI)
03 CLK 500 cabrio (Mom's)
2006 C230k (Dad's)
1999 S420 (Mom's/Dad's)
2000 C230k Sport sedans
2001 CLK320 Cabrio (Mom's)
1995 C280 My First Mercedes-Benz... (155k miles. EXCEPTIONAL AUTOMOBILE. Was Very hard to let go of!)

Thanks David. I will drive it as you said I should (I am half Italian -- so I will drive it long-term once weekly to give it that Italian Tuneup). Won't having the computer codes checked reveal a faulty OVR? With all the potential problems and fixes in the electrical and fuel systems, I do not want to do anything more unless I am absolutely certain.

I also forgot to mention that last year, I replaced the spark plugs with Bosch Platinums, and I replaced them again last week or so with another set of Bosch Platinums. Now, I am confused because of the debate about "to Platinum" or "not to Platinum." I think that I will replace the brand spankin' new Platinums with the Bosch regular that my car book suggests.

Donna,
First of all, you don't need to fill up at Chevron exclusively, I mentioned Chevron by name because I thought it would be a recognizable brand. Shell, Mobil or any of the well known brands should be fine.

Carbon buildup is a natural occurance in gasoline engines because gasoline is basically made up of complex carbon molecules. One of the purposes of long drives is to enable the engine to 'blow out' any carbon deposits, this is where good detergent gasoline helps. One note, never rev the engine up (or floor it) until after it is at normal operating temperature.

Regarding the Techron additive, you should add it according to the directions on the bottle and it's generally a good idea to have the oil changed after you've finished the treated tank of gas.

__________________
Glen Tokuhara
Beauty & the Beast and the wagon that could!

Donna,

No, the OVP will not come up when you read the codes. I would change it no matter what. It's only a $50 part and takes less than 5 minutes for someone that knows where it is. This is such a common problem with these cars I can assure you the results will be good.

And as Glen said, be sure and only drive it hard once the gar is up to operating temperature (about 85 C).

And of course, don't use the platinum plugs. Have them changed with a good Bosch copper plug. Supposedly the platinum plugs can break apart in the cylinder, or something of the nature?

__________________
2006 E350 w/ 155k miles (Daily Driver)

Previous:
1993 300E 3.2L Sedan w/ close to about 300k miles
2003 E500 Brilliant Silver (Had 217k miles when totalled!)
1989 300E with 289,000 miles (had for <1 yr while in HI)
03 CLK 500 cabrio (Mom's)
2006 C230k (Dad's)
1999 S420 (Mom's/Dad's)
2000 C230k Sport sedans
2001 CLK320 Cabrio (Mom's)
1995 C280 My First Mercedes-Benz... (155k miles. EXCEPTIONAL AUTOMOBILE. Was Very hard to let go of!)

Donna you should try to drive this car out on the open road and run it hard sometimes. I have a '95 E320 that I drive on weekends (minimum 70 mph - 30 miles without stopping) and I notice when I first start it up after having sat all week long that the initial idle is slightly rough. I will probably start driving it a little more than once a week. In addition to being hard to start these cars do some weird things when the voltage starts to fall off.
How long do you go before you have to put more fuel in it? Gasoline can kinda go bad over a period of a year or so and can possible "gum up" the fuel system. The Techron should help this some.

a) Try to run it more at higher rpm - This will keep the battery charged.
b) Do the OVP relay as suggested.
c) Change the oil more than once/year.
d) Go back to original spark plugs.

The worse thing you can do to this car is drive it 3 miles, shut it down and then do it again after it has cooled down. Believe it or not this is considered "severe service" in the manual.

When was the last time you changed your coolant, brake and transmission fluid?

__________________
Jim

Hi donna another italian here . Ok I owned a 300E for yrs. Donna if your dont drive it much. I recomend a battery cut off switch. This will keep the life of ther battery. Or a trickle charger ,this will keep the battery charged all the time. I works out great if you own a garage,and can plug it in when you get home. So it says nicely charge over night. If your not into getting under the hood, you can have your local mechanic install one,or the battry cutoff switch you can buy it at any pepboys or local parts store. As all the other guys mention. Those
over voltage protection relays,can play with the cars brain and do some funny things.

hope this helps goodluck.


Guido
Factory MB tech 14 yrs
1993 500E

http://home.earthlink.net/~italianbenz