190E Tune Up
 

So I just bought an '89 190E and its been sitting quite a while, but it has very low mileage.

The car starts fast, and runs well (no smoke, no major missing), but the idle is a little rough. Off idle it is very smooth, however if you get into it, it pulls well until about 4300rpms then you just feel it totally run out of huff.

I've only driven one other 190E 4cylinder manual car, but I don't remember the power band.

I ordered non resistor Bosch plugs (rock auto had 6 left), cap/rotor, resistor wires, air filter, and fuel filter.

I've put about 8 gallons of fresh 93 in the car, it was about empty when I got it.

Any other tune up areas I should look into on an M102?

I would also do the O2 sensor for peace of mind and just go over the vacuum tubing to make sure they are not cracked or brittle and replace as needed. I actually replaced all the plastic vacuum tubing and rubber connectors under the hood. Its a fairly simple and inexpensive task. You can purchase several feet of plastic tubing and several feet of rubber connectors at Napa for cheap. I would also order the check air valves for the EGR and the air diviter (if it has one). Everything else is just you normal transmission flush, power steering, coolant, and make sure the S belt is in good shape and not cracked or wearing. I have the m103, but I suspect that the m102 should pretty much have some of the same components.

Replace all fluids and filters and replace all ignition components with factory spec units is what I would do, to establish a baseline reference point.

Hadn't considered the vacuum lines, Good idea.


The motor has 102,000 kilometers on it.


It's got green coolant in it, so flush to the good stuff is in order.


The guy I bought the car from claimed he had recently changed the oil, I'm inclined to believe him but by the time I work my way through everything else ill do an oil change anyway probably.


What type of oil does the 717 transmission take? My friends G wagon called for ATF in its 4speed but that was an older truck.

Did some Beru wires and rock auto had some Bosch plugs left that were the OEM ones. Car runs WAY smoother now.

As for the fuel filter, the filter than came off appears to be original, but if you tilt the filter you can hear/feel something big rolling around inside the filter canister like the element detached inside the can. I may cut it open out of curiosity.

I put on a new fuel filter, and an new air filter as well.

What is the air diverter? This car is a euro so no EGR or smog pump.

89 would be too early for the emission stuff.

Plugs ,fuel filter, clean air filter, will make a big difference.

My car (m103) had a similar issue for a long time. My injectors where partially clogged.

Try a bottle of redline fuel additive before you start spending some serious coin on things that dont need replacing. If that does not help, injectors will be in order.

Vacuum should read at least 12hg. give or take. (not 100% sure) If you have an economy gauge, it should be almost pegged to the left running at idle, and 3/4-2/3rd, when at idle in drive.

It's a manual, in neutral it doesn't peg the left side of the economy gauge but it sits pretty close.


The next time I'm over there wrenching on it I intend to just start replacing vacuum lines. It's cheap and a few look questionable. So even if they aren't a current problem a few look like they are about to become one.

Everything the others have said, and...

I replaced the OEM fuel filter on my car, too. A few days later, after noting no improvement on the interstate, I bought a new fuel pump.

Things got interesting after that. The car seemed to come alive, and now runs vastly better.

Another thing, I could hear the fuel pump running fairly loudly from inside the car. The new pump can be heard, too, but is much quieter.

Mine has right at 300K on the odometer. Many parts I've replaced recently were OEM, so I think I, and the previous owners, got good service from these parts.