What you can do is take off the air cleaner housing and start the engine and use some brake cleaner and spray it around the hoses and see when the idle changes. This will give you the general area. Then you can narrow it down.

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1990 190E 3.0L

Alright thanks, heading out to the garage right now to try that

Spray fuel injectors too, they may also be leaking

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1990 190E 3.0L

Did that vacuum test, still cannot find the problem to the rough start and hesitation, only happens until you rev past 1500 then it's fine and gone until you restart the car. Fuel accumulator ?

Air flow potentiometer?

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1990 190E 3.0L

Thumbs up potentiometer ..

Installed the new behr fan clutch last weekend and took the benz downtown for a stop and go city test.
The temps still rise rapidly up to around 105 in heavy traffic or after a highway session but in moderate traffic its around 100
Turning the car on after sitting for a about 10 mins the temps are at are 115ish
Would coolant flush and thermostat help things
First pic is in stop and go and second is when restarting the car
Also this is when my misfiring symptoms pop up
Ive really about had it when this car

It appears that you are going piecemeal with the cooling system. All have to be replaced on your car that is almost 30 years old. Here is the system: water pump, radiator, thermostat, all hoses, overflow tank and coolant. I owned a 190 and live in the desert down the valley from Ismalley. We have 118F summers for 3-4 months. While the 190 didn't run the coolest, I never had a problem with the cooling system.
And I would still replace the coil to cure your engine problem.
Anziani
'97 CL600 56K

Kofi:

There is nothing wrong with your cooling system. Normal operating temps will be around 80-100c. It is common to get a temp spike when the car is off. The heat has to go somewhere when the cooling system is not pumping.

As long as you are somewhere in the 80-95 range while cruising down the road at speed, everything is fine. It wouldn't hurt to flush the cooling system, but likely won't help you at all with lowering your temps.

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Eugene

10 E63 AMG
93 300te 4matic
07 BMW X3
14 Ford F-150 Fx2

One person saying to replace all, another saying all is fine ?? I don't want to replace parts to just replace parts I want to find the root cause of my problems. I also bought a new coil along with wires,cap,plugs and rotor and problem persists. Had a mb shop we work with at work check the the potentiometer and it's fine. Vacuum tested the whole intake side of engine and nothing.

The cooling system has nothing to do with your hot stall problems. Yes, your car is running a bit warmer than it did when it was new, but it is still running within the tolerances. When the gauge goes in the red, THEN you are overheating. Aside from that, leave it alone.

Your engine issues have everything to do with heat. Some component is getting hot, expanding, or distorting, and causing your fuel/ ignition issues.

You need to isolate, and test. Next time the car stalls, try and restart while spraying ether in the intake. That will tell you straight away if it's fuel or spark.

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Eugene

10 E63 AMG
93 300te 4matic
07 BMW X3
14 Ford F-150 Fx2

This is my temp. A/C on, dual high speed fans on, viscous clutch engaged, 40 mph in stop and go traffic, ambient outside temp 106*F, thermostat removed (I just removed thermostat yesterday). It was a lot higher until I started moving. My cooling system is in fact working properly, but I have my dual aux fans directly wired to the a/c clutch so that when I use the manual cabin switch either hi or low, the clutch engages. Also, when the temps climb and the high speed fan is triggered, the clutch automatically engages, thus creating extra load. However, my clutch bearings are wearing out on my ac, but as you can see because of the ambient temp being 106*F, I dare not touch it until the fall when temps drop down to the 80s. So my suggestion, as mentioned before, is to adjust the water-coolant mixture to 70/30 or 80/20 to have your car run a bit cooler. Unless you are experiencing ambient temps as high as 100+ and your ac bearings or other pulley bearings aren't creating extra load, your cooling system should be within proper range, otherwise expect slightly higher temps. Also, you can try removing the radiator and putting a water hose into one of the ports and give it a good flushing. Reverse flush also. Then do the same for the engine: flush everything out with the hose until you get pure clear water. Button everything back up and add the water-coolant mixture. Don't worry about the tap water issue either, your system will be fine just as long as you are running some coolant in the system to prevent the calcium deposits from scaling up. Our tap water does satisfy the minimal drinking water requirements and according to the MB manual, this is ok.

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1990 190E 3.0L

You have a vacuum problem .Looking at the economy gauge on the picture and the rev counter sitting on zero .Its telling me you have a vacuum leak some place . Economy gauge sits to the left on idle and moves to the right on accelerating .

So its mid winter here in Toronto, car is acting up again.
1. Still having misfire problems after hot restart.
2. Car stalls in traffic as if its starved for fuel and will have to restart to get going, (wont shift up and and holds at certain rpm then shifts really hard from 2nd to 3rd, this shifting problem happenings rarely)
3. As soon as i installed my winter tires, I'm hearing a howling sound from the right rear side that's on audible from 0-60 km/h then goes away after driving for 10- 15 mins
4. I've changed the whole ignition system minus the coil and ezl, fuel filter is about a year old. I remember the p.o telling me his mechanic changed the fuel pump relay when it wasn't starting, was thinking to start there ?
also how can i do a smoke test to find vacuum leaks

Winter time is the #1 time when a worn out EHA starts having problems as it fails to adjust based on feedback from the ECU. I didn't read the whole thread, but if you haven't changed it in a long while, try that. It's a 5 minutes swap with a known "good" one that doesn't leak to eliminate one more variable.

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03 CLK430 Cabrio 211K Pweter Silver/ Oyster Leather
90 300SEL 214k Pearl Black/ Alto Grey/Black Leather

Prior: 85 190E, 88 300TE, 89 300TE, 90 300E 2.6, 90 300TE, 92 300E 2.6, 91 and 93 300SL, 87 Ferrari Mondial Cabrio