Sorry if this has been answered already but I couldn't find it. I bought a 190E at a yard sale. Yes, a yard sell for 200 bucks. Body is in excellent shape along with the interior. The guy said the Fuel pump relay was bad. Well, the relay is good. It was the pump that was bad. I installed the pump with the excitement of rollin in my MB but it won't start. If you spray a little fuel in the air intake it fires right up but quickly dies from stravation. I've replaced the fuel pump, fuel filter, spark plugs, wires, cap and button and i drained and flushed the gas tank. I have good fuel pressure coming in to the fuel distribution and out. I have fuel pressure at the cold start valve. But no fuel will come out of the four lines from the distribution. So I decided to break open the fuel distribution (cause there was a extra one in the truck) to maybe see what was going on inside. It was clean but the o-rings around the pump inside it were trash. I replaced them and clean everything really good. Put it back on and still no fuel will come. As i dug around under the seats I found 3 electromagnetic pressure actuators there. So It seems the guy was thinking the same as me, "it's not gettin fuel". But why? What am i missing here? Think it's a vaccum problem? Or does that system need to be primed? I thought I could talk to the local MB dealer, but well he was a real SOB and wouldn't tell me anything other than just bring it in. So please, if you have any suggestion let me hear them. Thanks in advace

Getting fuel to the fuel distributor doesn't count on that car!

You MUST have 85psi of fuel pressure, takes 60psi to 'push" the injectors open.

Connecting a gauge to the cold start injector would be the first step.

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator

I had the same problem last year on my 2.6 when i did the headgasket and replaced everything that needed to be replaced. After everything was assembled, it cranked but wouldn't fire. I unplugged the line going into the injectors and there was no fuel going into the injector but there was fuel going into the distributor. Somehow i just decided to push down on the fuel metering plate while somebody cranks it, and then it sputtered to life. I guess i was reallly lucky and that could have been much harder and probably is for most people.

Thanks for the ideas. And holy s#@%. are you serious on the fuel pressure!!!!!!! Think i'll backtrack the fuel line and see if any leaks and put a fuel pressure guage on it. I got the pump from a junk yard. But have a new too I'll try the new one tommorrow if it doesn't rain me out. Going to also trying pushing down on the FMP before i swap pumps. Any other ideas let me know. I'll keep you guys posted and thank you for suggestion

M.B.Doc is very serious about the fuel pressure.

Fuel pumps are one of those things that you can't skimp on. - Buy new.

The pumps rely on fuel going through them to be lubricated. A used example that has sat in a wreck or on a shelf for a long time maybe be suss.

Do try pushing on the air meter plate. If the car has sat for a while with no fuel going through it, it could be stuck.

You should notice that when you push on it with proper fuel pressure, it will be much harder to push than when you have no fuel pressure.

With the ignition (but not the engine) ON, if you push the air meter plate, it should cause the injectors to squirt. The gas would then run down inside the bottom of the intake manifold just under the butterfly since the engine isn't running and sucking it into the cylinders. I've never worked on an M102, but I am assuming the setup is similar to M103.

Try using a mechanic's stethoscope on the injectors. When you push the air meter plate with ignition ON, you should hear them squirt.

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-tp


1990 300SE "Corinne"- 145k daily driver - street modified differential - PARTING OUT OR SELLING SOON - PORTLAND OR. AREA - PM ME FOR DETAILS
1988 560SEL "Gunther"- 190K passes anything except a gas station
1997 S420 - 265k just bought it with a rebuilt trans. Lovely condition

Ok check the fuel pressure at the cold start valve and it is showing only 16 psi with the junk yard pump. So thought I'd put the new pump on and well guess what....still just 16 psi. I followed the fuel line all the way bank to tank and found no leaks. I doubled checked all connections. No leak. So what do you guys think now or should i say which direction do i go? Fuel pressure regulator? Or disconnect the fuel line and blow air through it? Or?? I tried push down on the Fuel meter plate and there was no change. So ummmmmmmmm.....now what ??? (lmao)

You replaced the fuel pump and fuel filter. Did you verify that the Fuel Accumulator diaphram is not defective, allowing fuel to go back into the gas tank, causing your fuel pressure to be low?

Also, there is a screen filter on the fuel distributor where the fuel line connects. It only takes a few minutes to verify that is isn't blocked up.

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1993 190E 2.3
2001 SLK230
1971 LS5 (454) Corvette Convertible

yeah slk230red, i removed that filter and checked it. It wasn't blocked. The fuel accumulator diaphram has not been checked. How would you test it to see if it was good or needs to be replaced? And also thinking about it, that filter was on the return side of the distribution. Is that the correct side? I was kinda baffled on why it was on the return and not the feed side. Maybe you could enlighten me on that. Thanks

The Fuel Accumulator is on the return side because it has a diaphram and spring inside to hold fuel pressure so the engine re-starts quickly. If the diaphram/spring is defective, fuel will bypass the diaphram and return to the gas tank via the rubber hose attached to the rear of the Fuel Accumulator.

You might try pinching off the hose or disconnecting the hose on the rear of the Fuel Accumulator and blocking the rear outlet with a short hose and blocking it with a bolt and clamp.
Then try checking the fuel pressure to see if it is higher than the previous 16psi.

Just a thought without buying any parts to see if you can isolate your low fuel pressure problem.

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1993 190E 2.3
2001 SLK230
1971 LS5 (454) Corvette Convertible

Ok that sounds like a good plan.. Think I'm going to "walk away" for today. Get back on it Saturday so I post my results.

ok back with my results. I was going to plug the accumulator off but decided to have my wife cycle key while i was under just to make sure. Wouldn't you know it the line from fuel filter to rail had a leak. I moved it by accident and fuel shoot out. I replaced it and did the same as before this time for sure no leaks. I checked the pressure at cold start and have 80psi (and purge)while cranking and with key off it is holding 42psi steady.The car will start and stumble around like it wants to run but it won't stay running. You can kinda work the throttle but it still acts like its not getting enough fuel. LMAO we're getting closer!! Throw me some more ideas......please...... oh and by the way the ole wife has stopped giggling at me now since she heard it start anyway..still debating if I'll let her ride in it LMAO

Sounds like you're making progress.

Is the fuel fresh?

Before spending money on parts, I would check the Idle Control Valve. Make sure the hoses on both ends are in good shape and are securely connected (they get hard and brittle over time).

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1993 190E 2.3
2001 SLK230
1971 LS5 (454) Corvette Convertible

I put two gallons of fresh gas in it. Should i put more? I know it supposed to have a two gallon reserve but i do have the rear jacked up so not sure if that might have a little effect on it. On the idle control valve, it runs toward the radiator and down to a little plastic like check valve kinda on the backside, Right?? I checked the connector (to the check valve)to see if it was getting power and it is, but not sure if it is working or not. Does it hum or anything when the key is on or what.? I know I keep wearing you out with question but you seem to be my only "lifeline" on here. lol

Since the car now has enough fuel pressure to almost run, try adjusting the lamda tower screw a 1/4 turn in either direction. Make a mental note of the direction & see if you can then keep the engine running. If worse go the other direction. You shouldn't have to adjust more than 1 complete turn in either direction.

You will need a long 3mm allen wrench. Push the allen down & then turn.

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator