Hello all. First off I have spent several hours searching trying to solve this issue... I've been dealing with diesel too much. haha

Car: 1984 190e 2.3l 5 speed

My brother bought this years ago. (I've posted on this forum about it) He typically drove 190 during the winter. He did this because of the hot starting problem. It's been there for years, It has gotten worse recently. I bought the car from him and have been driving it the last week.

Engine below 80f: Engine cranks and starts in 5 sec or less.
Above 80f (sitting all day, but outside temp is 80f plus): Cranks and starts in 10-15 secs maybe more.
Engine fully warmed up: No start.

Honestly starts better the colder it is.

I've use a spray bottle with gas.. Sprayed into air intake, and it will start. Brother has used either, but I'm not a fan.

Things done: OVP relay fuse ok, jumped ovp relay pin 30 to 87's, ok. Fuel pump relay jumped 30 and 87 for 2 mins during no start after getting home from work, no start still. Eng cranks fast. Has a new battery. About 2 years ago it got new spark plugs, cap and rotor. Less than 20k put on since then.

Read possible causes as fuel accumulator, cold start valve, weak spark, ovp relay, cracks in solder in fp relay, and cis distributor.

Lots of post seem to indicate accumulator as the problem in this instance. I thought that running fuel pump would rule it out. Is that a false assumption? When I get time I'd like to check to see is accum is leaking past diaphragm.

Anyways before I spend $ on parts.. Just hoping for input. Thanks

__________________
Dave

1985 190D 2.2 auto--gone
1975 240D 4-speed--storage
1985 500SEL--daily driver
1985 300TD--bad rust, soon to part out...
1982 300SD--waiting on engine from RD
1984 190E--storage
1996 Dodge 2500 Cummins--daily driver

That may be somewhat the nature of the beast. Sitting in the sun all day in warm weather the engine doesn't think it's "cold". Cold enrichment depends on coolant temperature and the systems were calibrated lean as possible for emissions reason, which in my experience degrades cold starts in hot weather and warm starts when coolant temperature is not quite down to ambient.

Also, all the cold start enhancements are in the "E" part of the system. Mercedes lauded the KE system saying that even if the electronics failed, the engine will still run, but I found out that if the electronics don't function the engine is nearly impossible to start cold. In this case it was a failed OVP relay, so the ECU didn't have power and none of the cold start enhancements functioned.

Since you say really cold starts are okay there are likely no serious problems with the E-part of the system, but on a 30 year old car a thorough check of all the connectors to the control unit and sensors is a good idea. A little bit of corrosion on a pin or receptacle can have an effect.

On a warm or hot restart try adding about 1/4 to 1/2 throttle travel after the first couple of cranking revolutions, and see if that helps.

The KE system is kind of a kluge. It's complicated, finnicky, and its behavior can change with time. Rather than trying to get it to work ideally as it should, the easiest solution is often to adjust your operating habits to the system's eccentricities.

Duke

So are you saying it starts well when you spray gas in the intake? Does it start well this way consistently?

Cold starts are always 100% ?
How is the idle when running?
Will it restart only with ether/ gas when hot? Ever get lucky?

__________________
Eugene

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

Yes cold starts everytime

Car runs great. Has a slight stumble at idle. Sometimes idles at 1000 rpm or so. Needs addressed... sometime. In the past the car had 'chugged' Replaced the cap rotor and plugs... About 2 years ago (again had the same issue) and problem went away.. This car does seem to foul up cap and rotors fast. Normal? Just realized we did compression test on car. Numbers a bit low. ahh.
190E "chugging"

Yes with some fuel added to air filter inlet.. it hasn't failed to start. still will usally crank 5-10 seconds but will start. The car used to hot start better. (less crank time)

__________________
Dave

1985 190D 2.2 auto--gone
1975 240D 4-speed--storage
1985 500SEL--daily driver
1985 300TD--bad rust, soon to part out...
1982 300SD--waiting on engine from RD
1984 190E--storage
1996 Dodge 2500 Cummins--daily driver

The symptoms you describe are classic bad cap and rotor (loss of spark) symptoms.

The starting when you spray gas in is the dead giveaway that it is a fuel issue. I would cross everything off of your possible list except the fuel dizzy.

Cold start valve only works when????? Cold!
Fuel accumulator and fp relay where eliminated when you jumped the pumps to no avail
I'm still going to hang on to the weak spark thing
Ovp might solve the high idle but is usually accompanied with an abs light. More than likely its your idle switch needs adjusting or replacing.

I would disconnect an injector line and confirm fuel flow. That would kind of cross off the fuel dizzy. (Disconnect and test all to really cross it off). I would toss a bottle of redline fuel additive to see if it helps.

If you remember buying the cap and rotor was it oe? Bosch? If not, Change those first. The aftermArket ones don't last for chit.

__________________
Eugene

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

Have only used Bosch caps and rotors.

Thought what the heck.. Put on on new cap and rotor today. Still has same issue. Also had spare coil. Put that on. Nothing changed. Cranked 15 seconds this morning and after work..

__________________
Dave

1985 190D 2.2 auto--gone
1975 240D 4-speed--storage
1985 500SEL--daily driver
1985 300TD--bad rust, soon to part out...
1982 300SD--waiting on engine from RD
1984 190E--storage
1996 Dodge 2500 Cummins--daily driver

The symptoms are of hot leaness (very evident - spray fuel in, it starts!!).

Two primary components are in play:
1) Water temp sensor.
2) Electrohydraulic actuator (EHA) on the fuel distributor (FD).

If the resistance of the water temp sensor is too low, the mixture will be driven in the lean direction. With a hot engine, unplug the sensor (high resistance). This simulates a cold engine. Is starting improved?

The EHA is the main mixture controller. When it is unplugged it is in the neutral position which is slightly rich. Try a hot engine start with the EHA unplugged.

If neither of these checks has any influence, there are some other components which can be tested, however these are the easiest and have the greatest influence.

Frank.. Anyway you could point out the location of EHA?

__________________
Dave

1985 190D 2.2 auto--gone
1975 240D 4-speed--storage
1985 500SEL--daily driver
1985 300TD--bad rust, soon to part out...
1982 300SD--waiting on engine from RD
1984 190E--storage
1996 Dodge 2500 Cummins--daily driver

The EHA is a rectangular device located at the left rear of the FD, attached to the body of the FD by screws, with the plug towards the rear.

Haven't been on line long enough to post...

Things I've done on lunch breaks.

Cap and rotor- no change
spark plugs gapped to .032 Bosch yttrium super plus- no change
Fuel filter- no change

Found out the engine can hot start.. if I unplug the coolant temp sensor. I think.. By the thermostat there are 3 sensors.

One with 3 wires to it and 2 prong connector. One in the middle with one wire and one prong connector. (<----unplugging this one. It has an effect on running.)The last one has 2 wires and one prong connector to it, also the top is red.

If I unplug the one wire one prong connector I can start the engine with less than 5 sec crank time. I have to quickly plug it back in once started. Exhaust smells rich at that point.

Soo I thought the sensor must be bad. My brother has an 1984 190e too. I switched sensors with his. His car starts and runs fine, and mine still doesn't. Does unpluging the sensor just put a band aid on the problem? Must have something else going on. I haven't disconnected the eha yet..

To add to issues with the car: It runs ok. It just has a rough idle and while accelerating you can feel the engine shudder.. sometimes. Nothing terrible, but it feels like a misfire. When the car starts, sometimes it idles and runs fine and other times it surges to 1200 rpm and then fall down to 500 rpm. At that point it is running rough. I have to feather throttle for a min or two until it smooth out. Car doesn't smoke or burn oil.

Today I filled up with gas and added a bottle of redline fuel system cleaner. I believe someone on the forum recommends that additive strongly. 12 bucks. whoa

__________________
Dave

1985 190D 2.2 auto--gone
1975 240D 4-speed--storage
1985 500SEL--daily driver
1985 300TD--bad rust, soon to part out...
1982 300SD--waiting on engine from RD
1984 190E--storage
1996 Dodge 2500 Cummins--daily driver

Back to driving the 190e this week. 240d is having some issues.

Past two weekends I have...

new fuel pump (old one was loud, new one is quiet)--- no change
Put on a good (brothers car) air flow pot, fuel injectors, and fuel reg--------No change
Switched a good working eha----------------------------------nothing noticeable
Worked on adjusting lambda/eha duty cycle------------------My idle is lower. and stumble is gone on accel... thought i had fixed it.... Nope. No hot start still and even a long cold start today..

I am having trouble with the eha duty cyle adjustment. I have turned the adj ccw about 8th of turn (leaner?). Test drove. I have no notable stumble on accel like before.. My idle is still poor, but it is idling! 700 to 800 rpm. I've been finding little info about specs for the m102.961 (pretty sure this is my engine) Currently with engine at 80c coolant temp, my voltage at pin 3 on x11 socket is 7.48v and 13.2v is battery voltage. I rev the engine and voltage goes from 7.48 to 4,5, and 6 volts. Some post indicate 54-50% is right.. Honestly I can't wrap my head around this adjustment.

I'd like to set ignition timing. Spec on under hood plat is 5 btdc +-1 <---Idle and vac line disconnected? Would this be worth is.

I'm at a loss with this car. Should I go back and start with basics? Is this vacuum related? I've checked to leaks, but there seems to be lots of potential spots where I couldn't visually check.

__________________
Dave

1985 190D 2.2 auto--gone
1975 240D 4-speed--storage
1985 500SEL--daily driver
1985 300TD--bad rust, soon to part out...
1982 300SD--waiting on engine from RD
1984 190E--storage
1996 Dodge 2500 Cummins--daily driver

where would i find the water temp sensor?

I would check , or even replace the engine temperature sensor .
If engine is at a cold start then fuel is made rich .
If engine is at hot start fuel is made lean .
So every start is in a rich stage .

Your sensors -last one at the rear e/t/s

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Thank you for responding, and for posting the pic. Just so I am clear, the most rearward sensor on my engine has a black round electrical plug with 4-prongs.
Is this the engine temperature sensor ? P/N 008 542 32 17?

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Steven
1989 260E (276K miles)
1995 E320 (50K miles)