Doc Bernard

Okay, I was told if you have a question on a Benz, this was the place to ask.

I just bought a Benz, and here's my story:

Bought it used.
1st gear was a bit sluggish, but once it shifted into second, had good acceleration and smooth running.

Drove it for a couple hours, no complaints other than what was mentioned above.

But when pulling a small grade in a residential area..........it suddenly started running extremely rough, and would not accelerate past 20 MPH.

Pulled over, put it in park......idle was fine. So, spent a few hours trying to find a vacuum leak (something similar happened to me in another type of vehicle, and it was a vac line) Found one minor one, but did not fix the issue.

Finally had it towed to a friend's mechanic, where he has his Benz worked on. He delved into the issue and he found that two of the fuel lines from the distributor were not getting fuel. Bought another distributor........no joy, same problem still. How many fuel lines supply the distributor? if more than one, are there filters on each?

If you know of a thread that addresses this issue.......PLEASE link me. Or if you can point me in an area to research or troubleshoot, I would be eternally grateful. I bought the Haynes repair manual, and I plan on be up all night researching this issue, as this is my only car.

Doc Bernard

Oh.....and the next morning, it would not start. I am in Southern CA.

Couple of other symptoms:

Backfires through the throttle body when accelerator is pushed
Economy gauge slams into the red when I give it throttle

oakley

when i bought mine, the fuel filter had not been changed in who knows how long. replaced it, and it restored some of the power to the engine that was not present, definitely goin uphill! i know my car sat up for a while, and i figured that was as good a place to start as any, bein as i hadn't joined any of the forums yet. just a thought. get ready to do some reading, and research, you will find these folks are most knowledgeable and willing to help sort out your issues.

Inherited1

I have looked high and low in many forums but only found similar but not exact same problem with my 4 cylinder 1986 gray market MB300E (i think it's a 190E American market) that I inherited from my father who passed away.

This car sat for at least a year without starting. It does start, one click, more often than not. It drives like a dream when it behaves. But at least 2 or 3 times while driving around town, whether stopped on a light or driving on highway, it would seem like it wants to die. I would tap the gas lightly until it goes away. Black smoke comes out of exhaust while I lightly tap the gas.

While it's acting up, and i step on gas full on, it dies. It would take 5 or 6 tries to start it back up. When stopped, I could feel the problem's onset when the RPM rises on its own to 1500 or higher revving itself up and down (black smoke again), while stepping on brakes. Again, I would tap the gas lightly until it goes away. Black smoke disappears when it goes back to normal.

The fuel pump relay (part 003 545 24 05 located next to AC relay 002 545 1205 by the battery) was replaced when I took it to an MB service shop (not dealer)and the young mechanic could not solve the problem. He also changed the plugs, wires, fuel filter and air filter. No good. Took it to other non-MB mechanics and they're stumped as well.

It feels like there's a piece of dirt stuck and rolling around in the fuel system since it only happens intermittently, whether the tank is full or less than half. The first thing I tried was to put fuel cleaner additive in the tank, but after a few bottles I figured it's not the problem. I almost want to drain the tank to have it cleaned and or replace the injector jets.

Someone also suggested to have the relay wires checked since the AC is also not functioning and the AC relay is next to fuel pump relay. Any help or point to the right direction would certainly be appreciated. Thank you

vanir

Doc Bernard, the fuel distributor supplies the injectors, so there are four lines coming from it to the injectors on the M102 (2.3 four), if two of those were not getting fuel then the distributor head was worn. There is a problem about replacing these, they're very fiddly items being the heart of the jetronic injector system (the "computer" just provides mapped spark and has nothing to do with fuel control), they're very finely set and should only be reconditioned by a celebrated specialist with good references. Over the counter reconditioned changeovers are hit or miss, all the popular brands have very bad reputations locally so I went to a race builder specialising in MB restorations and track cars, which was competitively priced with off the shelf brands but both far more accountable and worlds better in references without a sales pitch.

As for simply replacing the fuel distributor with a second hand unit, even more hit or miss. Maybe it'll work or maybe it'll be even worse than the one you replaced.

There are also some other fuel valves around the manifolding which wear or petrify (these are 20yr old cars so most of the rubber seals have petrified from heat/age and will need replacing if disturbed, or may already be leaky). Injector seats also petrify and you might want those replaced, injectors themselves aren't very expensive for these so a new set of OEM replacements might be in order.

You also want to make sure the fuel pumps are checked and not sweating or noisy (mine is the 2.6 so has two, I don't know if yours has two or one). Fuel filter is between the pumps (under rear near tank) so get that replaced while the pumps are being checked, it won't cost much.

And if you go to someone actually worthy of replacing and resetting your fuel distributor, they should be able to troubleshoot any other problems, or identify the fuel distributor as the cause of the existing problem, quite effectively.
Search in your local area/state with parameters something like "fuel system mechanic bosch ke-jetronic." or instead of "ke-jetronic" try "CIS-E"
It's basically the same system as any 70s-80s porsche and any 80s MB, should be plenty of specialists around. But a specialist in this system is definitely what you want, don't do over the shelf or home handyman or even common mechanics for the injection on these. They can become extremely expensive, or quite reasonable in price, walk the right side of that line and do it right first time to save big dollars.

vanir

I think you'll find the 300E with the four cyl option is an M102 2.3 litre, so a common engine with the 190E 2.3, but is a different body type. Things like AC and electricals might be different.

The way I understand it from browsing around is:
The 300E was essentially made for the 3.0 litre M103 six, but has other engine options.
The 180(E)/190(E) was essentially made for the 1.8 litre and 2.0 litre M102 four, but with the intention a track version with a worked engine would become available as a homologation sports version (2.3-16) and soon afterwards a downsized version of the M103 six in 2.6 litre also became an option.
So badging kind of sort of follows the promoted engine capacity of the model. The model before yours was the 280E with a 2.8 litre (which is basically an engine option on a more generic 230/250 series four/six midsize-midmarket or "executive-class sedan" that stretches back to the 1960s).
The 190 is an entry market compact and the flagship of the C-class that followed it. Yours is an E-class, slightly bigger/heavier.