Stall and Stumble.........

[prevost3000]

Hi. Prevost here again.

New problem. 89 190E 2.6 gas auto.

When I press the accel from a dead stop, it wont go.

I can clearly count 1-2-3 and on 3 it speeds away.

When i hit the pedal, i see the economy gauge drop deep in the red during 1 and 2. I am pushing down what seems to be maybe 1/4 to 1/3 pedal travel, nothing that I would seem lead foot. I am a very nice takeoff guy. (gotta save that timing chain/belt, i always think)

On the freeway, its a speed freak, so I dont think fuel filter, the air filter looks decent, the plugs are new, the wires are all tucked away in the holder. the economy gauge is usually in the black most of the time, except on accel from stop.

Any ideas?

[Mike Murrell]

Your title says "stall and stumble", but in your post you mention depressing the accelerator and it won't go.

To me, this sounds like 2 completely different things.

Which is it?

[mctwin2kman]

Well first off the W201 has a 4 speed tranny that starts in 2nd gear unless floored. So that would cause a slight hesitation at take-off if you push the pedal enoug to get it to drop to 1st.

Second the vacuum economy gauge will show red when accelerating, unless you only push the pedal a hair. This gauge just gets a vacuum feed from the engine, and vacuum when accelerating is low as it should be. My 2.3 190E does the same exact thing. Then again it is slow to begin with so I floor it from stops to get my first gear and some good acceleration.

What you can do is run some fuel injector cleaner through and check you plugs, cap and rotor to see if they need replaced. Test the O2 sensor as well just to check it. Replace as needed. But the 190E was not exactly a speed demon off the line when new so do not expect it to be after 17 years.

[prevost3000]

Let me clarify that the 'stall' meant that it stalls or hangs up when the gas is pressed. 1-2-3 and 3 it takes off. The Stumble is at idle with the trans in drive, stopped with the A/C on, the idle seems very low and the engine shakes and rattles. I put seafoam in the gas tank with some premium 91 octane fuel from Texaco. I will pull the plugs again to inspect, and the dist cap and rotor too. I hate accessing that bottom hex bolt.

When you say starts off in 2nd unless floored, are you saying that if you push it until that black switch behind the pedal presses, then it goes to 1st gear? Please clarify what the black switch is for.

[mctwin2kman]

The switch is for KickDown. There are two ways that the 190 Tranny will downshift, one is the Bowden cable which will drop the tranny one gear. The other is the KickDown Switch that activates the KickDown Solenoid on the tranny. This will drop it to the lowest possible gear for the given speed. About 3/4 throttle will drop it to 1st after a short delay. Full floor and activate the switch and you get a quicker drop down but still delayed. Put the shifter down to 2 and then back to D while stopped will drop the tranny to 1st as well. That way you actually start in 1st instead of rolling a few feet in 2nd then the abrupt drop down to 1st. This was changed around 1992 in the W201 and the tranny in those starts in 1st. Newer MB's have a switch on the center console for Winter and Sport mode, Winter starts in 2nd and has a 2nd Reverse gear as well. Summer or Sport starts in 1st and has higher shift points. The 190 does not have this and by design starts in 2nd for the ealier vehicles.

If you have a hesitation off start then it could be your mixture is too lean, in which you can richen the base mixture a hair to give you better take offs. But if you got the shakes as well then you could have any number of issues, from a vacuum leak to bad plugs, wires, cap and rotor, to a bad O2. Check the plugs and cap and rotor and the O2 sensor as well and visually check all rubber vacuum connectors for dry rot and cracking. Then if all that is good we will move on to the other stuff it could be.