'91 300TE -Taking bets on Rich Fuel condition

[Rusty Boltz]

300TE in South Texas w/ 87K miles and severe fuel delivery issues. My prime candidates are O2 sensor, OVP, Idle control valve, EHA, or fuel distributor (possibly plunger sticking). History of car prior to my purchase a week ago: brought to dealership for engine stall and die when acclerating from a stop, next complaint smoking on acceleration, again stalling, smoking and poor gas milage. These same complaints were repeated 6 or 7 times when car was taken to dealer for service. I know this because I insisted on having the service records when I bought the car from the dealership as a "great example of MB durability". The last service entry was in March when the dealership sent the car through the shop for used car evaluation and prep.

I purchased it about a week ago. There is no indication that the original problem was fixed and I see all the same symptoms including black smoke and milage ranging from 9.5 to 12.1 mpg.

Would you care to bet (vote) on the actual cause of the problem? You see my favorites above. Perhaps you can think of another possibility. It is hard for me to believe that our MB dealer had the car in so many times over the course of a few months without solving this if it is fairly simple. At $70 per hour they should have even solved it if it has more than one cause.

I have an appointment at Corpus Christi German Motors on Wednesday and will share the results of their diagnosis. I am new to the MB community and am still waiting on my W124 CD to arrive. See how good you are and vote on your favorite solution. I can't wait to fully understand my Jetronic System before putting this car into daily service and with the record that Ed Hicks Mercedes-Benz service department has with the car, I prefer to take it to strangers and give them a chance.

Bob Murry
Former Volvo Owner
91 300TE
92 Miata for autocross
Grand Caravan for trips

[Rusty Boltz]

Forgot to add that the Mass air flow Meter could some how be contributing to this possibly if the engine controls think more air is going in than actually is?

[Rusty Boltz]

I took the car by this PM to CC German Motors to leave overnight for my appt tomorrow. The nice lady there wouldn't take my car in when she found out I had just bought it and the dealership had sold it to me. She insisted that I take it immediately to the dealership and that they would have to help me.

I was skeptical and had lost all my trust for them when I found out that the car was not really a one owner car as they had stated and the car immediately started moking and the rear muffler fell off.

The service manager was very friendly and took the car in. He said that since this is a problem that they had worked on before and not fixed, that they would take care of it. Adrian my salesman was also friendly and nice, wanting to make everything allright. They are keeping the car tonight and will see if they can find the problem tomorrow.

I had written these people off as sleazeballs and was prepared to never do business there again. It looks like I may have been mistaken about them and that they are eager to make things right and to keep me as arepaet customer.

I will post the results of the diagnosis and repair when I find out the problem. The symptoms again as first noticed:

And these all seem to be after the car warms up...
Black smoke on acceleration
Hesitation or engine may die leaving a light
<10 mpg
very poor acceleration after warming up, can maintain speed at about 2500 rpm
sometimes have to pump the accelerator to get above 5 mph and then finally kicks in
when it does jump above 3000 rpm huge clouds of black smoke
sometimes the transmission will not shift right and I have to get the rpm pretty high...then it tends to jerk when it shifts

After chatting with the head tech at cc German Motors I am also considering the catalytic converter as a possibility.

Hopefully life with my first MB will go smoother in the second and third weeks.

[dpetryk]

I would bet money on the fuel distributor as the problem.